Sunday, December 30, 2012

Is Winter Over?

There is a great deal of consternation about whether we are going to have a winter. A little snow/ice could happen as soon as this Thursday here in NC, maybe no t so much in VA. In the bigger picture, longer range models are simply not favorable for cold or snow (There are some climate model exceptions).

So ... how do we settle the dilemma? Pay more attention to the actual weather and less to Computer Weather Models being at odds with Climate Models.

The Stratosphere is warming over the Arctic. That feature correlates very well with sending real cold southward. Therefore any model showing anything more than a temporary warm-up that transits warmth north to build blocks should be questioned.  Below is the current cross-section of the polar vortex. The upper atmosphere warmth is full column.
The Arctic Stratosphere is warming.
This event is highly correlated with mid-latitude cold.
Image Source: NOAA Climate Prediction Center
So... what we have right now is a predictor of cold weather to come. Projections support the idea of a terrible middle to end of the month.  
This image is a 10 day projection near the top of the stratosphere showing the warming in the Arctic and cold displaced deep into the US. 

If this projection verifies then the Eastern US is in trouble.
Notice the warm area off the SE Coast, a stormy signal?
Image Source: NOAA Climate Prediction Center.
In previous years this kind of formation has sacked Great Britain and the rest of Europe with some Little Ice Age - like winter weather. Our continent would seem to be overdue for something that severe despite the cold conditions that dominated 2009-10 and 2010-11. While we suffered those years, Europe SUFFERED. 

The question is whether we get some tropical forcing in the West Pacific and a jolt of energy to bring real winter into the Eastern US. I suggest watching Alaska. If that state trends warmer than it would suggest that High Pressure there will push the colder air SE. Another region to watch is Mexico, a persistent jet stream crossing that country from the Pacific would represent a lowering of pressure to draw the cold in and introduce more Winter Storm opportunities.

So, its time to go back to basics. Follow the satellite images and the overall weather to solve for downstream effects, While the Stratospheric warming event is not a perfect correlation to cold here in the SE US ... it is good enough to question weather models that would lead one to believe that winter is dead.

Here is a great New Year's Resolution: Follow actual weather more and models less ....

Monday, November 19, 2012

A Case for a Cold Stormy Winter

A combination of a Negative NAO and Negative AO in October has a strong correlation to Eastern US cold and/or snow.  Those who want to roll the dice on a cold, stormy winter can look to 2002-03, 2009-10 during this decade.   I do have to mention that the indices were strongly positive in October preceding legendary winters like 1977-78.  It is interesting that snowy winters like 1981-82, 1968-69, and 1960-61.  I discounted 1974 because it was a blazing La Nina year.  2006 is an oddity because it was a promising El NIno Winter which the phenomena simply shut down.

So, we have an argument for cold, stormy winter.   The fact that the legendary winters were excluded might be an indicator of the correlation working in 
+AMO (Warm North Atlantic) situation but not so much when it is negative.  There is no such thing as a perfect linear correlation in weather.

Data Source: NOAA Earth Science Laboratory

This composite Temperature anomaly from the NOAA Earth Science Laboratory covers the bonafide El Nino Winters featuring a -NAO/-AO below -1.00 in October (I excluded 2006).  The pattern of cold is what I believe will resemble the upcoming winter.

This is a composite of Sea Level Pressure anomaly.  Take note of the lowest pressure being at the 50N/50W position that argues for my idea that the upcoming season can be dubbed the Winter of the Nor'easters.  50/50 Lows favor snow/ice in NC and VA.  This data is also from the NOAA Earth Science Research Laboratory.

This plot is not dissimilar to the PNA
      That's all for now.  Later this week it will be time to discuss a potentially really cold start to December.

Wednesday, November 14, 2012

Finally! The Winter 2012-13 Forecast

To El Nino or not, Is that really the question?

Here in NC and VA many El Nino winters are loved because they do tend to be colder an usually contain a few good winter storms.  La Nina, on the other hand, is maligned for warm, dry, winters that lead to hot summers full of bugs and pests.   Therefore, the first question usually asked is whether to label a winter as an El Nino or La Nina.

Occasionally we see the crazy La Nina's like 1976-77 and 2010-11 which blocking develops in NE Canada and leads to endless cold.  There are also occasional El Nino's that feature warmth closer to South America that lead to endless gray 40-50 degree rainy days.  Thus, while the labels have some reliable generalities, I think it is a good idea to analyze the whole globe for clues. The fact is that it takes a moderate to strong El Nino or La Nina to rule the roost.

What are the Oceans telling us?

There is always the question of whether the ocean temperatures are being driven by the atmosphere, "Top-Down" , or vice versa (Bottom Up).   A good winter El Nino features plenty tropical storminess near the Dateline.  I find another feature even more interesting.  Look at the Ocean Temp anomalies below:

  1. Warm east of Hawaii, Cold Gulf of Alaska:  This feature appears to be stable and promotes a -EPO.  An indicator of a cool to cold Winter if the signal holds through the season.
  2. Warm pool near Mexico:  Promotes low pressure at that location.  This promotes drainage of cold air from the north and a subtropical jet stream.
  3. Oops!, I skipped 3 but do not want to re-do the Chart :>)
  4. El Nino?:  Sort of.... warm water in the right place to promote low pressure and feed the all important Jet Streams.  I think just enough but not too much.
  5. Cold Water near Darwin, AU:  Tropical cold water promotes High Pressure.  At that location it would mean a downhill slide to #4.
  6. Cold Southeastern Seaboard:  This can be an indicator of cold to come if the water is caused by rain and cool Autumn.It can also be a bummer that promotes NC and parts of VA being skipped instead of targeted by Nor'easters.
  7. Neutral Water near Greenland, ice already east, but warm further south: Too much -NAO snows on LA, MS, AL, FL, GA, and SC, while skipping us.   That signal is very mixed in regards to the NAO.  Winters with plenty of fluctations seem to be the most exciting.  Tough read...
The oceans seem to be indicating a much different Winter than the non-winter of 2011-12.  There are definitely ingredients for a season that is biased cold with enough "El Nino" around to send storms into the Gulf of Mexico to the East.  The cold water near the SE Coast is not something Winter lovers want to see unless it is being caused by the atmosphere ("Top Down") and not given a chance to feedback.   Hurricane Sandy and 2 Nor'easter non-effects on NC and limited in VA has me worried that a Confluence (Skip Zone) might be out there.

Other Signs and Wonders

The beautiful colorful sunsets this autumn and feverish Squirrel activity are 2 observations also supporting a cool to cold winter.  I don't think an acorn from our Oak Tree has even hit the ground!

More Seriously...

While I have my concern,,,,  this appears to be a 2003-04 type winter that  featured 2 snows and a mega-icestorm.  There will be plenty of back and forth swings in the SOI, plenty of frontal passages, and a base state that is cooler than average in the east (-EPO).  I am also impressed by blocking in the West Polar Pacific (called the -WPO) which, if it is stable through winter would provide an ample supply of Siberian air.

So, in a nutshell:

  • At least 2 degrees colder than average.
  • Plenty of storm, opportunities should yield 2-3 disruptive winter storms.  Hopefully the traditional school calender does not end in late June 2013.
  • If we go through December and see NC and VA being skipped by Nor'easter, it will be time to lower expectations about snow,

Monday, October 29, 2012

Thought about Sandy as she approaches NJ

The long wait for Sandy is over.  As she approaches the coast the "Hurricane" aspect will rapidly transform to a full blown Nor'easter.  Similar to Irene (2011) expect belts of high wind and heavy rain/snow to form far away from center.

At the center of the system, the wind will become a non-event b/c of a lack of pressure gradient.   The big problem (also similar to Irene - 2011) is the central pressure of 943 mb (Strong Category 3) that may yet reach the Category 4 range.  Expect storm surge flooding well above and beyond the bogus Category 1 designation given to the system right now.

One of my lingering concerns is the storms hurricane force+ winds being displaced up to 175 mile s SW of the Center.  Could this imply that those well SW of the Center could see the highest inland winds?

My expectation continues to be that Central VA, north and east of RIC will see top wind gusts in the 60 mph range (original expectation 50-70 mph).     Here in RDU, the National Weather expects gusts to 45 mph.   There is some argument to go a tad higher but... what's 5-10 mph among friends?   On the other hand ... we do not seem to be a very windy area.

Stay safe and stay informed about the weather.  Sandy is a historic storm with a 1000 mile sphere of influence.   I am sure that there are variables that are not being well accounted by weather models.

I am impressed with the overall 72 hour accuracy of model solutions in regards to the track of the center.  It will be interesting to see what happens after the storm completes it Nor' ricane to Nor'Easter cut-off low transformation.

Thursday, October 25, 2012

Hurricane Sandy a massive scale is bad news for Eastern US

My long breaks between writing have been unavoidable.  Winter is coming, therefore I know there will be plenty to write about.  Also my job transition is coming more under control.

The subject right now is Hurricane Sandy.  She is already transitioning to a massive nor'easter with a tropical core en route to a probable disastrous impact on the middle and north eastern seaboard and thousands of square miles inland,  The satellite image below  shows the tremendous inflow from across the equator and from the central Pacific.   

Hurricane Sandy well on the way to becoming a Nor-icane (Hybrid Storm)
Image Source: University of Wisconsing SSEC

This storm is not going to live the life of a traditional Hurricane that hits land and fades quickly.  This system will not only make its presence known in the form of gale and hurricane force winds but also coastal flooding and even snow!  

Tomorrow, we will look at the storm track and projected impacts.  Now that Sandy is on the move speculation will transition to greater accuracy in forecasting.   The ECMWF 3 PM run was particularly disconcerting because of a direct hit on the DelMarVA peninsula followed by a track into North Central VA.  Regardless of where she hits, there will be a lot of damage done.  If she took that more SW route then my friends and family along I-95 from RIC on north would get their 3rd hurricane-force impact in less than 10 years!  

Have a good night!  It's going to be a long weekend.

Tuesday, August 28, 2012

Massive Hurricane Issac strengthens as he closes in on landfall

It is still important not to focus on the wind speed as much as the pressure and the size of the system. Hurricane Issac's central pressure is 970 mb, a strong Category 2.  Storm surge near and east of the landfall will very likely be well above what one would expect off a Cat 1. Take a look at the massive sphere of influence that Issac has in the below water vapor image.  Take notice of the tremendous inflow from the deep tropics and the buildup of heat and moisture at the SE US Coast which is far away from the storm center.

Anytime a storm has this influence, it means business!
Image Source:  Univ of Wisconsin SSEC
Issac still has about 12 hours over water.  I would not be surprised to see Category 2 wind speed at landfall and a Category 3 pressure.  We really need to hope and pray for a landfall point less unfavorable to New Orleans.  No one is interested in seeing the city fill with water again.

Monday, August 27, 2012

If the NHC will not promote Issac to Hurricane, I will!

Even though the NHC calls Issac a 70 mph Tropical Storm. I confer upon the storm the title of Hurricane. Issac's 981 mb central pressure is at the low end of Cat 1 (almost Cat 2) and the Eye is becoming apparent. Therefore based on the 
Saffir-Simpson Scale (The detailed description) Issac easily fits into Cat 1.

Last year's devastating storm Hurricane Irene was a "Category 1" that contained a central pressure of 942 (Category 4!). People stayed in the impact area who would have fled. There was a miraculous preservation of life despite the flooding + amazing local wind damage for a "Category 1" storm.

So, when you examine the stats of the hurricane factor in the Central Pressure when determining likely impacts. Even though the highest measured wind speed may be low it does not mean that the ability to produce small scale wind events of much greater damage potential does not exist. The worse problem near the coast was the record storm surge at Oriental, NC, easily equal to a Cat 4 hurricane.  Another argument against Irene being only a Cat 1 was her wide area of damaging influence.  60-80 mph winds spread up the I-95 corridor, far from center.

Sunday, August 26, 2012

TS Issac appears to be making the LA Coast his target

Those following me on Facebook know the questions and consternation about the destiny of TS Issac.  At first my thought was that the -SOI from Aug 7 - 15 would have successfully introduced a progressive weather pattern thus turned the storm toward the east coast of FL and the SE Coast.  It appears that 2 years  of blocked weather patterns are not easily swept away.

The biggest winner so far in determining the TS Issac track has been  David Tolleris correctly chose the Central Gulf as the target zone.  Now that Issac is past the disruption of dry air and Hispaniola + Cuba we will now see the various tools used to determine the track of the system become more accurate.

In the Water Vapor image below I highlighted the frontal system stretching across the middle of the country and the current direction of the moisture plume preceding Issac.  Eventually Issac's circulation will be influenced by the front and be turned right.  The question is whether that influence and the weakness between the Bermuda High and the Inland heat ridge draws the storm sooner or later.

Source: Univ of Wisconsin SSEC
There are good reasons to be fearful for the whole region. Not only is New Orleans likely to be affected to some extent, there are a great deal of Refinery assets at risk,   Gasoline prices are already exorbitant.  Outages in the limited US Refinery capacity would seriously impact the price of gasoline and other oil based products.

Sunday, August 5, 2012

Ernesto not worthy of a name

What I would now call an alleged Tropical Storm, Ernesto, was looking good yesterday.  The steering flow strengthened late yesterday which both increased his speed and resulted in the center losing its alignement with convection.  Further damage to the storm took place when he ran headlong into dry air.  Now it takes imagination to see more than a strong tropical wave.

Ernesto's central pressure has been a bit unconventional for a tropical storm.  His lowest pressure has been near 1006 MB, not all that impressive.  His winds and cyclonic spin were baroclinically enhanced by high pressure located N and another W of the system.  Now that those relationships are weakening, Ernesto has to power himself via tropical means (oceanic heat) if he wants to succeed going forward.

Here is a Water Vapor image showing Ernesto (South) and an open Tropical Wave affecting FL.  So, why would Ernesto not simply be a bigger version of the FL Tropical Wave?
Source: Univ of Wisconsin SSEC
Being weaker or non-existent "Ernesto" will track most west and will eventually impact southern Mexico and Belize.  If anything substantial finds its way into the Bay of Campeche then it may be possible for a storm to be worthy of a name.

Saturday, August 4, 2012

Ernesto slows and strengthens, Nice Day here in NC

Ernesto is surprising me a bit. He slowed to 18 mph (which helps the storm structure stay together) and instead of running headlong into dry air and shear has a nice environment to develop. The other system over the Bahamas yesterday is now moved just east of FL and is running out of space but still has inflow and outflow... so that one may bother FL with heavy rains + strong T-Storms ...BUT... not an organized banded storm.

Here in NC we are benefiting from the simplest of weather principles: High Pressure flows into Low. Therefore a NW flow and drier air is making for a great summer day.  Time to mow the yard so that next weeks rain and t-storms can grow it back again :>(

Source: Univ of Wisconsin SSEC

Friday, August 3, 2012

Tropical System over Bahamas, Explosive Potential

Take notice of the vigorous tropical wave over the Bahamas.  It has a jet stream feeding it and a source of baroclinic energy (NE upper level winds) west of it.  This is something that can birth a tropical storm or a hurricane very quickly because of the hybrid (tropical + veering winds) situation.  take a look at this water vapor image from the Univ of Wisconsin SSEC.

Source: Univ of Wisconsin SSEC
In addition to the potential tropical threat another in an endless series of disturbances will pass through from the NW triggering more Thunderstorms including the damaging heavy and severe variety during the weekend.  So, keep one eye on the sky when doing activities this weekend.

Thursday, August 2, 2012

Changes afoot but Summer heat to linger a little longer

If I could take my size 12 foot and kick the weather pattern, it would be done.  The fact is that the Pacific is not just in cold mode, its really cold!  Since weather patterns generally move west to east in our hemisphere it means that drier air than normal ends up in ridges of high pressure overland that outperform and clog up the weather pattern.

There is a proverbial foot kicking the weather machine. Even though cooler air from Canada is not going to reach us this week the march toward a weak El Nino or at least a whole lot less La Nina is clawing its way forward.

The big tipoff that getting cooler will wait until mid-month is the westward tracking of tropical storms in the West Pacific.  This is an indicator of high pressure dominating their eastern seaboard.  Therefore the ups and downs of the jet stream lead to a ridge that heats our region.

Here is the track of Tropical Depression #12 in the West Pacific and its forecast indicates that cooler air is not coming until at least late next week - mid-month.

Source: Joint Typhoon Warning Center
It is a disappointment not to get cooler air by the 4th.  I should have known that the "Super Glue" (TM) that has stuck this weather pattern would not be so easily dislodged.  Do not lose hope! Out in the equatorial Pacific the little island of Tahiti has gotten some rainy days (lower pressure) and Darwin, AU basked in bright sun.  This reversal of fortunes is felt in our region around the 15-16th (like last year).

So, delayed but not denied. Fall, like last year is still coming early.  Our only consolation this summer was the fact that a "sort of " trough was over the region much of the season promoting thunderstorm activity but failing to get temperatures to the normal realm.  Winter has some questions but generally appears colder than average and a sharp departure from the alleged Winter of 2011-12.

Sunday, July 22, 2012

Summer 2012's familiar pattern soon coming to an end

This summer is not going entirely as I expected.  June was supposed to be the back and forth month with the wildest weather and the only blast of heat.  July and August was projected to be more reasonable as the last vestiges of the 2 year La Nina had faded away in a transition toward an eventual weak El Nino.  As we know the summer has not gone entirely as planned.

Some good news is that the dog days of Summer will end earlier than last year's Aug 16 date.  Until then a familiar pattern centered further west than 2011 has dominated.  An active and fast Pacific jet stream that is common in a La Nina/Low AAM situation has not yet broken down.  Furthermore, global AAM tanked just in time for the historic heat wave here in the East.  Take a look at the below Water Vapor image from the University of Wisconsin SSEC.
The fast Pacific Jet buckles in the NW US bringing a trough and cool conditions there.
Heat gets concentrated on the SE side of the Jet Stream in a process similar to a heat pump.
In 2011 the jet buckled further inland leading to the epicenter of the heat being over NC.  This year it is further west, locking in the heat over the Central US.  Our region suffered a relatively brief intrusion of outrageous heat at the end of June - early July and has stayed in the "Ring of Fire" periphery since that time.  Therefore since the historic highs most days have been in the mid-upper 90's with plenty of opportunities for rain from the disturbances being transported in by the torrid Central US High Pressure.

Changes are afoot as the La Nina-ish Low AAM condition is receiving a big jolt from Mountain Torque.  My oversimplified explanation is that the buildup of air particularly at the Andes has led to an ever so slight decrease in the earth's rotation in exchange for a jolt of momentum into the atmosphere at the equator.  It will take until the first week of August for the changes to work its way through the global weather machine to NC and VA so just a little more patience is required.

Image Source: NOAA Earth Science Research Laboratory
Note: The negative torque in late June/early July was not
THE cause of the heat wave, but b/c of the season be suspected as
a contributor toward the crash in AAM.
I suspect that some of the long range forecasting problems of recent years has some basis in the best data occurring since the 1960's and especially the 70's.   The period of 1980-2000 was relatively mild compared to the cold Pacific (-PDO) warm Atlantic (+AMO) of this decade.  Our current ocean pattern was more reminiscent of the 1930's and 1950's which still hold most all-time heat records and lots of extreme weather. Therefore we are missing the data that might have led to better accuracy in  forecasting the extremes of recent years.

One good thing is that even stubborn conditions like the extended La Nina must give way to her brother El Nino if only to temporarily satisfy imbalances in the economics that drive the atmosphere.  This and several other influences point the way to a cold winter with a very cold one as a possibility.  Until the Pacific warms and the Atlantic cools the overall propensity toward La Nina and extreme weather can be expected.  

Sunday, July 1, 2012

Heavy Thunderstorms may be taking aim at Raleigh-Durham Overnight.

My last check of Radar before heading to bed is a cause for concern.  A fast moving line of heavy to severe thunderstorms is crossing the mountains and seems to be taking aim at the Triangle.  So far the organized system is maintaining its shape and intensity and could be a problem several hours from now if it continues to encounter a favorable environment.

A cause for concern is the vast area of temps in the Low 80's North and West of RDU that would raise the likelihood that the system will hold together through the night.   Oddly enough, areas south and east of the Triangle feature a broad swath of upper 60's to low 70's .  Here in Garner we seem to be in a buffer zone between the warm and cool areas as it is a nice 75 degrees outside.

Dean Grubbs
The Dean Report

Saturday, June 30, 2012

My Perspective of the Supreme Court Decision about the Affordable Healthcare Act

The Supreme Court Decision about the Affordable Healthcare Act requires reading the decision and the dissent. The News Media and Politicians are certainly avoiding the finer points of the ruling. They also are avoiding why Chief Justice John Roberts sided with the left leaning Justices.

It will surprise you that I agree with the decision. To be clear, I find the Law abhorrent and believe it to be ultimately harmful to many whom it claims to help. After reading the Decision it seems more hazardous to oppose the decision than to agree.

Justice Roberts rightly pointed out that it is not the duty of the Court to determine whether a Law is wise or "fair". The job of the Justices is to validate Constitutionality. Sadly, that duty relies more on Court precedent than the original Constitution. In this case the Ruling is based on the fact that no existing Federal activity have been found to be unconstitutional.

My suspicion based on the Roberts opinion and dissent is when the Conservative Justices wanted to strike the Law down the Chief Justice had determined for himself that he could not join with that idea because he had figured out that the Law was really using the Tax system to set different final amounts for those who have purchased health insurance and those who have not.

The fact is our country has convoluted tax laws that bill each person differently based on a multitude of variables, whether a person is single, married, have children, have a mortgage, buy their own health insurance, and a long list of other ways that decrease or increase one's tax liability. The Tax system has been used  for decades to reward some choices and discourage others.  Its spider web of complex rules set the stage a long time ago for a Law that rewards those who purchase Insurance and penalizes those who do not.

Despite what we have been told by the President, other Politicians, the media, and others the actual Law really uses the Tax system to work its magic. The Chief Justice and the rest of the Majority reached this conclusion by ignoring what they were told and reading the Law. Some argue that Chief Justice Roberts rewrote the Law to make it pass.  According to the Majority and Dissenting views the only thing that occurred is that the Chief Justice READ the Individual Mandate section and used both his knowledge of Law and previous decisions to determine that the words describe use of the Tax Code.  Could the fact that the reported requirement that everyone purchase or be covered by a Health Plan was called an "Individual Mandate" cause concern that the Law really was not intended to be a Tax on uninsured taxpayers?  

Those who dissent argue that the Law should be struck down because of the insistence of those who voted for and signed the Bill into Law that it is not a tax. Therefore since taxation was not intended the Law as written then only the Commerce Clause could be used to justify the Individual Mandate thus as agreed by the Majority, rendering the Law unconstitutional.   
I found it interesting that the Government argued in legal briefs that Federal taxation power "created a basis for upholding the Law" Source: LA Times.  In my perception the idea of judging intent is dangerous enough in cases like those judged by the Supreme Court.  Whether or not Legislators and the President were being incompetent or malicious when insisting to the public that the Individual Mandate was not a tax (Source: ABC News) is immaterial because of the legal briefs.

The question is whether the Supreme Court best serves the country by deeming a Law "broken" and striking it down OR determines how a Law actually functions and educating the public?  My position is that the Chief Justice's approach of focusing solely on the written law was the most non-partisan of the whole group.  How would it have been "conservative" if those who wanted to strike the Law did so because of their perception of what was intended?  I would like to understand what the Justices who trend liberal were thinking, were they looking for any reason to uphold it?  It appeared that the Liberal-leaning Justices mostly signed on to the Chief Justice's viewpoint with only limited commentary.  I would have preferred to see more from the majority than only the Chief Justice.

Now the the issue becomes whether the public will accept the Tax that was once called "The Individual Mandate". Will the public wonder about how many more creative ways the tax code can be used to coerce taxpayers that are worse than what already exists? It certainly changes the healthcare debate and places the issue front and center this November.
   I am relieved that the Chief Justice exposed the moral hazards of the Tax Code and believe that alternative ideas like a Flat or Consumption Tax may gain more traction in the coming months.

Wednesday, June 27, 2012

Will the coming heat wave smash records?

It is taking me a while to get back with the weather groove. Now that my transition to new duties has been complete for several weeks it seems that the love for weather and the urge to figure out what is happening is back. 

While my original summer forecast accurately predicted heat and tropical storms in a wild June the incoming heat ridge is OVER THE TOP. One NC Meteorologist is calling for a historic period of triple digit heat.  Weather Underground has been projecting Sunday highs at RDU (during Thurs 6/27/2012) to hit 108!!!  Take a look at the National Weather Service'e Heat Index forecast for Sunday.

When investigating some reasons for the obnoxious heat I found that the biggest driver has been a dive in Global Atmospheric Angular Momentum (AAM).  In its low state, weather is most like La Nina.  Here in the east it means heat and tropical storms. That does not necessarily mean heat 100% of the time but it does indicate dominance of ridging.   Here is the good news.  AAM is at or near a bottom.  The SOI has been in strong negatives (between -34 and -49) for the past 4 days.  This indicates the coming of a rising AAM trend and ultimately cooler summer weather.  I am still confident that the season will end in the normal range despite the torrid heat of the next several days.  Here is the Relative AAM Chart from the NOAA Earth Science Research Laboratory.

Keeping plenty of cool water available when driving would be a terrific idea.  Staying indoors when temps pass 100 is even better.  Be careful not to overwater your gardens.  A quart at the roots of most plants (every other day) + mulch heavily will give the best protection.  If we really hit 104, 108, and 106 (Sat-Sun - source Weather Underground from Wed 6/27) then I have no idea what can keep plants from taking damage other than building a Canopy.   SOAKING leaves invites disease!

Stay cool and please be safe.  Drink more water than you think you need, even indoors.  It is also advisable to run major appliances at night and keep the lights off as much as possible during the day to conserve power for AC use.  We definitely do not want to place Progress Energy in a bind.

Monday, June 25, 2012

Debby and companion frontal system in process of playing out split scenario

Florida is literally drowning in heavy rain from the frontal structure attached to TS Debby.  Fortunately that feature is in process of splitting away from Debby as it moves into the Atlantic.  This water vapor image from the University of Wisconsin SSEC shows the bulk of the water vapor aligned with the frontal structure and losing connectivity to the low-level "Debby" storm center:

Debby's fate remains unclear.  Normally storms in the NE Gulf tend not to intensify rapidly.  Even though the water is warm it does not run deep, therefore the heat content needed to power a tropical storm is limited,   My opinion is that she drifts north into the FL Panhandle due to being drawn in by strong convection there (falling pressure).

Our next big story here in NC and VA will be the big heat coming this weekend.... 
Dean Grubbs
The Dean Report

Sunday, June 24, 2012

Tropical Storm Debby following a Hybrid Playbook

Tropical Storm Debby has surprised forecasters by moving toward the FL Panhandle and following more closely with the GFS Model solution than the usually more dependable ECMWF and HWRF.  While I am late to the Debby forecast track derby, it seems like my own philosophy regarding types of tropical storms may bear fruit in determining the ultimate outcome. Here are 3 observations that may explain the reason why the GFS has been more helpful.

  • Debby is a hybrid storm containing a tropical warm core and a baroclinic frontal structure.  The two structures do not appear very united which is good news.  The GFS manages baroclinic features in a more helpful manner than tropical.
  • Heat ridge centered over TX and AK might have been underestimated as an influence.
  • Disturbances that are diving into the Eastern Trough are stronger than I expect at this time of year.  A stronger trough pulls the tropical storm north into it.
This water vapor image  shows the poorly organized center of Debby and the expansive area of convection that is dousing Florida.  The hybrid structure is connected to a stream of moisture originating from the Pacific.   Take note that the energy is not building the center of Debby,
Image Source: Univ of Wisc SSEC
National Weather Service Radar shows rain bands moving inland over FL.  The question is whether the  stormy weather's destiny is different than the tropical storm center known as Debby.  Another issue is whether the non-tropical piece of the storm system affects Florida more greatly than the Debby storm center's destination.

My suspicion is that the hybrid structure will follow the GFS idea of the storm moving through Florida.The Debby storm center will most likely decouple completely from the baroclinic structure and drift west.   Whether the storm generates into a formidable system and impacts LA or TX, dies out, or spins down over land is the next question.

Tuesday, June 12, 2012

Rainy, Stormy Weather to continue, glorious weekend is on the way

The Atlantic and Pacific tropics have joined forces to flood the east with humid unstable air leading to heavy rain.  This pattern appears set to continue for the next 36 hours before giving way to a glorious sunny weekend featuring highs in the low 80's, bright sun, and comfortable humidity levels.  Take note of the storm over LA and AR moving east that is dumping torrents of rain amid heavy thunderstorms.  Here is this morning's water vapor image from Univ of Wisconsin SSEC:

National Weather Service Radar shows the storm system moving east. I expect its flooding to be a newsmaker. It is well organized and the further saturation of the southeast that will come from this system stacks the odds even further AGAINST any sustained heat this summer.  A moist ground fails to heat as fast as dry and cools the air temperature by evaporative cooling and convective rain and thunderstorms.  The question for us in NC and VA is what role if any will the system play when it interacts with the cold front that advances into our region on Wednesday?

Wednesday, May 30, 2012

TD Beryl poised to soak most of the Triangle

Beryl's circulation and shield of rain strengthened overnight as her center hugs the coast moving NE.  Radar indicates heavy rain and thunderstorms emanating far from center.   It appears that the Triangle, particularly east of Highway 64 is poised for excessive rainfall, 2-4".  In the National Weather Service Radar image below , the banding features on the north side of the center are clearly visible.

Unfortunately the timing of the rain will impact rush hour.  The pre-frontal trough which Beryl is merging is already dumping moderate rain on the Durham area just west of RDU.  This sets the stage for a tough drive to work as rain caused slowdowns will build quickly.  Be patient and safe when driving this morning.

Monday, May 28, 2012

TD Beryl deluging heavy rain on drought stricken areas of the SE

Take notice of the well defined circulation over FL.  TD Beryl is a terrific example of how a hybrid storm that is powered by tropical and baroclinic forces can work mischief over land long after coming ashore. The spiral bands are clearly seen on the below National Weather Service Radar.

Over the next three days the depression will turn NE and dump copious amounts of rain over eastern GA, SC, and NC.  Here in the Raleigh-Durham area we can expect continued bouts of thunderstorms featuring heavy downpours. In this water vapor image the vigorous thunderstorm development in NC is an example of tropical heat and moisture colliding with a baroclinic force, a natural trough east of the mountains which is a frequent summer feature.

Source: Univ of Wisc SSEC

Also in the weather pipeline is an Arctic air mass that will bring a significant shot of cool air to much of the central and eastern US.  I think the computer projections of highs near 80 and lows near 60 are generous.  More on that soon.

Sunday, May 27, 2012

TS Beryl hitting land. Looks like a Hurricane.

The below Radar image courtesy of the National Weather Service looks more like a hurricane than a typical tropical storm.  It will not surprise me if the system is either upgraded or re-classified at a later date 

TS Beryl Update - Near Hurricane Strength

It appears that the improvement in overall structure paid off for Beryl as her top winds are estimated at 70 mph.  The potential for a damaging hit is greatly increased.  If Beryl were to reach hurricane strength she would be only the second hurricane to directly hit Jacksonville since 1871.

Storms like Beryl are interesting to me because even though the storm has tropical structure it is also being fueled by baroclinic features.  In the below water vapor image, I outlined a subtropical jet stream that is feeding the storm from the SW and strong northerly flow that is contributing to the "spin" on the west side of the system.

TS Beryl is a hybrid that is powered by oceanic heat and
baroclinic processes.  She is close to hurricane strength.
Source: Univ of Wisconsin SSEC.

In my experience, storms like Beryl can either have wide ranging impact and maintain strength for a long time or quickly break down as soon as the baroclinic assistance falters.  A baroclinic-tropical system is also called a hybrid storm.   Last summer's destructive Hurricane Irene was an incredible example of a hybrid system.   Despite alleged top winds of 85 mph (Damage near Oriental, NC suggests otherwise), the storm had a central pressure of 952 mb (Cat 4 would be under 950), and a massive storm surge that flooded areas that would have only expected high water in major hurricanes.  The storm also sent 70 mph winds and heavy damage along a belt far from center along I-95 through VA into MD.  Irene caused billions in flood and wind damage as she treked north through the NE US and well into Canada.

The question is: Will Beryl be The Lady or the Tiger?.

TS Beryl taking aim at Jacksonville, FL

It is not uncommon during summers that are transitioning to El NIno or in one to see early season tropical storms. In seasons like the upcoming summer upper level westerly winds in the tropics will either shear off the tops of storms before they can form or turn them away from land.  Therefore what storms do manage to form and threaten land are born much farther north and closer to land.  The good news is that the vast majority of such systems do not tend to be large or powerful.

TS Beryl has improved in size and structure.  Even though her wind speeds are not a cause for great concern, it is likely that when she goes inland a deluge of rain could lead to flooding and gusty winds down some trees and cause damage typical after hours of 30-40 mph winds.  Generally storms which are weak but large in scope tend to hold together for longer periods of time overland.  I am impressed with Beryl's structure.  Note the possible eye-like feature in the visible satellite.

TS Beryl appears to be developing an eye feature.
Source: Univ of Wisconsin SSEC
Even though the storm will ruin Memorial Day for many in FL and GA there is a blessing that can come from the rain that is expected in an area that has become very dry.   Heat ridges, such as the feature that roasted the whole region the past two summers do not tend to hold together over moist land.  The reason is that water vapor is lighter than dry air, therefore sabotaging high pressure development.

June still appears to be the month of summer that will contain the hottest temperatures and much of the remaining tropical storm activity.  Once past June we still appear on track for a moderate summer.

Sunday, May 6, 2012

Summer and Tropical Outlook 2012

Sorry for the prolonged silence. I have been involved in a job transition that has consumed my energy and attention.  Here is my Outlook for this Summer.  It will be shorter and more concise than in the past so please ask questions if more details are needed.

La Nina's effects not going quietly into the night

The ENSO (El Nino-Southern Oscillation) is an Oscillation which has been stuck in a La Nina phase for the past 2 years.   One could argue that some of the foundations of the prolonged La Nina were already in place during the 2009-10 El Nino.  There was the interesting characteristic of a non-El Nino-like excessive rainfall and flooding in northern Australia during that period.

La Nina generates a situation that leads to amplified, blocked weather patterns by the effect on global atmospheric angular momentum (AAM) by the cooling of the waters of the equatorial Pacific.  In general this means that ridges of high pressure dominate east of mountain ranges and land masses and troughs to the west,  The excessive heat of last summer and our recent non-winter were extreme examples of what La Nina can do.

Finally the pendulum is shifting in the El Nino direction but it appears that late Spring and early Summer will contain some lingering blocked weather patterns and hurricane potential.  Therefore, the hottest days of summer appear to be slated for June.  This chart shows the hole that AAM must climb out.  The trend will be our friend as weather patterns evolve into El Nino solutions but it will take some time for the uptrend toward cooler/milder summer weather can take over.

The AAM line is back in La Nina territory
In general there is an uptrend from March lows.
Summer Temperatures

June: The hottest month featuring the warmest days and I completely expect a streak or two of 95+ degree highs.
July:  I would not be surprised if the warmth of June ends in an East Coast or NE Gulf Tropical Storm. Cooler than average to moderate.
August: Near average temperatures with some back and forth as late summer processes attempt and ultimately fail to sustain a prolonged Bermuda High.

If not for some above average Atlantic Ocean temperatures in key regions (+AMO) it would be easy to see summer here in Central NC and VA to be below average.  The Ocean surface temperature variation is also a known Oscillation that is heading toward a negative dominant phase but not there yet.

Tropical Activity

Summers heading into an El Nino tend to not include high numbers/intensity of tropical storms.  Westerly upper level winds in the tropics inhibit storm development.  Overall activity should be below long term averages.

Storm tracks tend to recurve out to sea more quickly than La Nina seasons.  They also form north of the deep tropical regions and closer to land.  We call this "Homebrew" development.  Those storms are often weaker than the Cape Verde type hurricanes but there is far less warning before landfall.

Lingering low AAM is likely to enhance opportunities for early hurricane activity, even the long-tracked Cape Verde type.  Do not be surprised if June features the season's strongest storm.  I am deeply concerned about the NC Coasts, particularly those struggling to recover from 2011 Hurricane Irene.


As AAM rises weather systems will become increasingly progressive.   This means more frontal passages which will increase opportunities for rainfall compared to recent summers.  Watch in June for a crazy hot period that is followed be a tropical storm/hurricane or a prolonged period of heavy tropical sourced rainfall.

Overall, I expect the summer to feature normal to above average precipitation.

Looking Ahead

East Coasr Weather Warriors are salivating at the thought of a weak El Nino during Winter.  It means cold with excessive amounts of snow particularly in areas that are were buried in 2009-10.  If any major  high latitude volcanic eruptions occur in the coming months then the stage would be set for  an expensively cold season.                                                                  

Friday, April 6, 2012

Preliminary Summer Idea

This summer appears much less difficult to forecast than last year.  The big dilemma last year was resolving how much La Nina would relax before it returned again last winter combined with some cooling forces that had not yet begun to exert themselves.  Therefore I had 2 solutions that were opposites, record heat or cooler than average. As we know the outcome was extremely hot through Aug 15th when summer abruptly ended.

An El Nino is developing in the Equatorial Pacific.  The Southern Oscillation Index and Global Angular Momentum is already responding the warming oceans.  Our sudden end to Summer in March is also part of the weather pattern becoming free of the longstanding La Nina.

As one of many who suffered in last summer's heat, I am pleased to announce that temperatures this summer appear headed to a cool to moderate result.  Negative SOI correlates very well with an eastern summer trough which would give eastern Canada and the Great Lakes potentially no summer.  Here in NC and VA we would benefit from more frequent cold front passages that would moderate our temperatures and provide plenty of rain.  In the map below the green and yellow areas would be expected to be coolest, relative to average.

My final Summer and Tropical Outlook will be issued in May. I do not see anything on the horizon that would change the temperature forecast.  It will be great to have have a summer that being outdoors can be enjoyed and gardens flourish.

Sunday, March 18, 2012

Lower Gasoline prices requires wise energy and economic policy

The biggest impact of gasoline prices this time of the year is the poor valuation of the dollar combined with the Iran risk premium on the price of raw crude. As we get into late spring and summer some refinery units have scheduled required maintenance while others switch to summer state-specific formulations which allegedly reduce pollution. As we get into May and June there will be no excess gasoline inventory and prices will likely rise sharply if demand for the product is anywhere near normal.

The effect of increased US supply of crude would be to keep dollars here in the US where they can circulate. It will also lower the Iran/Middle East Risk premium off the base price, increased predictability of gasoline and other distillate inventory will lower the futures prices.

Removal of risk premiums would probably lower prices toward the $3 - $3.15 gallon area (My thinking is a 25% of the price is risk premiums). A shift in monetary policy to shrink the money supply (higher interest rates) and cleanse the dollar of toxins which are also lowering it's spending power would probably send gas prices to $2.50 or even lower. One reason that gasoline averaged $1.78 at the time of Pres Obama's inauguration was the collapse in money supply brought on by the financial crisis in 2008.

President Obama's policies to increase supplier costs (through taxes and regulations) and lower the reliability of supply (restrict drilling, exploration, deny Keystone) definitely plays a strong role in increasing the cost of finished product (gasoline). Fed Chairman Ben Bernanke along with Federal Spending that went from unacceptable(!) (President Bush) to destructive (President Obama) is flooding the US with dollars which are not backed by goods or services. Further distorting the economy is how ordinary people are not in the pipeline for those dollars YET bear the brunt of rising prices of goods and services that has resulted.