The hurricane season of 2010 arrives

By: Dr. Jeff Masters , 2:56 PM GMT on June 01, 2010

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The hurricane season of 2010 is upon us. With unprecedented sea surface temperatures in the Atlantic, El Niño gone and possibly transitioning to La Niña, a massive oil slick in the Gulf of Mexico, a million earthquake refugees in Haiti at the mercy of a hurricane strike, and an ever-increasing number of people living on our coasts, the arrival of this year's hurricane season comes with an unusually ominous tone. NOAA is forecasting a very active and possibly hyperactive season, and Dr. Bill Gray has said he expects "a hell of a year." However, our ability to forecast hurricane activity months in advance is limited, and we don't yet know how the large scale weather patterns like the Bermuda High will set up during the peak part of hurricane season. In particular, I very much doubt that we are in for a repeat of the unprecedented violence of the Hurricane Season of 2005, with its 28 named storms, 15 hurricanes, and 7 intense hurricanes. While sea surface temperatures are currently warmer this year than in 2005, that year featured some very unusual atmospheric circulation patterns, with a very strong ridge of high pressure over the eastern U.S., record drought in the Amazon, and very low surface pressures over the Atlantic. A repeat of 2005's weather patterns is unlikely, though I am expecting we will get at least four major hurricanes this year. An average year sees just two major hurricanes.


Figure 1. Tracks of all June tropical storms and hurricanes in the Gulf of Mexico, 1995 - 2009. Allison was a subtropical storm (coded blue). Image credit: NOAA Coastal Services Center.

The latest long-range computer model guidance suggests there's no reason to suspect that the first two weeks of this year's hurricane season will bring any unusual activity. Climatologically, June is typically the quietest month of the Atlantic hurricane season. On average, we see only one named storm every two years in June. Only one major hurricane has made landfall in June--Category 4 Hurricane Audrey of 1957, which struck the Texas/Louisiana border area on June 27 of that year, killing 550. The highest number of named storms for the month is three, which occurred in 1936 and 1968. In the fifteen years since the current active hurricane period began in 1995, there have been eleven June named storms (if we include 2008's Tropical Storm Arthur, which really formed on May 31). Five tropical storms have formed in the first half of June in that 14-year period, giving a historical 36% chance of a first-half-of-June named storm. Five June storms in the past 14 years have passed close enough to the Deepwater Horizon oil spill location to have caused significant transport had there been an oil slick on the surface.

Sea Surface Temperatures
Sea Surface Temperatures (SSTs) are at record high levels over the tropical Atlantic between Africa and Central America this year (Figure 2). As I discussed in my May 15 post, the area between 10°N and 20°N, between the coast of Africa and Central America (20°W - 80°W), is called the Main Development Region (MDR) because virtually all African waves originate in this region. These African waves account for 85% of all Atlantic major hurricanes and 60% of all named storms. When SSTs in the MDR are much above average during hurricane season, a very active season typically results (if there is no El Niño event present.) SSTs in the Main Development Region (10°N to 20°N and 20°W to 80°W) were an eye-opening 1.46°C above average during April. This is the third straight record warm month, and the warmest anomaly measured for any month--by a remarkable 0.2°C. The previous record warmest anomalies for the Atlantic MDR were set in June 2005 and March 2010, at 1.26°C. The Arctic Oscillation (AO) and its close cousin, the North Atlantic Oscillation (NAO), are largely to blame for the record SSTs. The AO and NAO are climate patterns in the North Atlantic Ocean related to fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores-Bermuda High. If the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), this creates a weak Azores-Bermuda High, which reduces the trade winds circulating around the High. During December - February, we had the most negative AO/NAO since records began in 1950, and this caused trade winds between Africa and the Lesser Antilles Islands in the hurricane Main Development Region to slow to 1 - 2 m/s (2.2 - 4.5 mph) below average. Slower trade winds mean less mixing of the surface waters with cooler waters down deep, plus less evaporational cooling of the surface water. As a result, the ocean heated up significantly, relative to normal, over the winter and Spring.

However, over the past two weeks, the AO/NAO has trended close to average, and trade winds over the tropical Atlantic have increased to near normal speeds as the Bermuda-Azores High has strengthened. SST anomalies have been falling in recent weeks, and will continue to fall in the coming two weeks, based on the latest forecast from the GFS model. While I expect that record SSTs will continue into mid-June, current trends suggest that by July, SST anomalies will be close to what they were in 2005. SST anomalies in the MDR could fall below the record 2005 levels by the peak part of hurricane season, August - October. Even so, SSTs in the Caribbean this year will be plenty warm to cause an abnormal number of major hurricanes. These warm SSTs may also cause extensive damage to the coral reefs, which suffered huge die-offs from the record SSTs of 2005.

Typically, June storms only form over the Gulf of Mexico, Western Caribbean, and Gulf Stream waters just offshore Florida, where water temperatures are warmest. SSTs are 28 - 30°C in these regions, which is about 0.5 - 1.5°C above average for this time of year. June storms typically form when a cold front moves off the U.S. coast and stalls out, with the old frontal boundary serving as a focal point for development of a tropical disturbance. African tropical waves, which serve as the instigators of about 85% of all major hurricanes, are usually too far south in June to trigger tropical storm formation. Every so often, a tropical wave coming off the coast of Africa moves far enough north to act as a seed for a June tropical storm. This was the case for Arthur of 2008 (which also had major help from the spinning remnants of the Eastern Pacific's Tropical Storm Alma). Another way to get Atlantic June storms is for a disturbed weather area in the Eastern Pacific Intertropical Convergence Zone (ITCZ) to push north into the Western Caribbean and spawn a storm there. This was the case for Tropical Storm Alberto of 2006 (which may have also had help from an African wave). SSTs are too cold in June to allow storms to develop between the coast of Africa and the Lesser Antilles Islands--there has only been once such development in the historical record--Ana of 1979.


Figure 2. Sea Surface Temperature (SST) departure from average for May 31, 2010. SSTs averaged more that 1°C above average over the entire tropical Atlantic and Gulf of Mexico. Note the large region of below average SSTs along the Equatorial Pacific off the coast of South America, signaling the possible start of an La Niña episode. Image credit: NOAA/NESDIS.

Wind shear
Wind shear is usually defined as the difference in wind between 200 mb (roughly 40,000 foot altitude) and 850 mb (roughly 5,000 foot altitude). In most circumstances, wind shear above 20 knots will act to inhibit tropical storm formation. Wind shear below 12 knots is very conducive for tropical storm formation. High wind shear acts to tear a storm apart. The jet stream's band of strong high-altitude winds is the main source of wind shear in June over the Atlantic hurricane breeding grounds, since the jet is very active and located quite far south this time of year.

The jet stream over the past few weeks has been locked into a pattern where a southern branch (the subtropical jet stream) brings high wind shear over the Caribbean, and a northern branch (the polar jet stream) brings high wind shear offshore of New England. This leaves a "hole" of low shear between the two branches off the coast of North Carolina, which is where Invest 90L formed.

The jet stream is forecast to maintain this two-branch pattern over the coming ten days (Figure 3.) This means that the waters offshore of North Carolina is the most likely place for a tropical storm to form during this period, though the southwestern Caribbean will at times have shear low enough to allow tropical storm formation. The Gulf of Mexico is forecast to have wind shear too high to support a tropical storm during the first half of June. None of our reliable forecast models call for tropical storm formation over the coming 7 days, though the NOGAPS model indicates the possibility of a tropical disturbance forming off the coast of Nicaragua on Friday.


Figure 3. Wind shear forecast from the 00Z GMT June 1, 2010 run of the GFS model for June 7. Currently, the polar jet stream is bringing high wind shear to the waters offshore New England, and the subtropical jet is bringing high wind shear to the northern Caribbean. This leaves the waters off the coast of North Carolina and southern Caribbean under low shear, making these areas the most favored region for tropical storm formation over the next 7 - 10 days. Wind speeds are given in m/s; multiply by two to get a rough conversion to knots. Thus, the red regions of low shear range from 0 - 16 knots.

Dry air and African dust
It's too early to concern ourselves with dry air and dust coming off the coast of Africa, since these dust outbreaks don't make it all the way to the June tropical cyclone breeding grounds in the Western Caribbean and the Gulf of Mexico. Developing storms do have to contend with dry air from Canada moving off the U.S. coast; this was a key reason why our first "Invest" of the year, 90L off the coast of South Carolina, never became a subtropical storm.

Dust expert Professor Amato Evan of the University of Virginia has posted his forecast for African dust for the 2010 hurricane season. Dr. Evan is predicting that due to plentiful rains during last year's rainy season over the Sahel region of Africa, and near average amounts of African dust observed in May 2010 and during the 2009 hurricane season, we can expect near average or moderately below average levels of dust over the tropical Atlantic during the 2010 hurricane season.

Steering currents
The forecast steering current pattern over the next two weeks is a typical one for June, with an active jet stream bringing many troughs of low pressure off the East Coast of the U.S. These troughs will be frequent enough and strong enough to recurve any tropical storms or hurricanes that might penetrate north of the Caribbean Sea. Steering current patterns are predictable only about 3 - 5 days in the future, although we can make very general forecasts about the pattern as much as two weeks in advance. There is no telling what might happen during the peak months of August, September, and October--we might be in for a repeat of the favorable 2009 steering current pattern that recurved every storm out to sea--or the unfavorable 2008 pattern, that steered Ike and Gustav into the Gulf of Mexico.

Summary
Wind shear over the main breeding grounds for June tropical cyclones, the Gulf of Mexico and Western Caribbean, is expected to be high enough over the next two weeks to give us an average chance of a June named storm. I give a 30% chance of a named storm between now and June 15, and a 60% chance for the entire month of June. There is approximately a 30% chance of a June storm passing close enough to the Deepwater Horizon oil spill to cause significant transport of the oil. See my post, What a hurricane would do the Deepwater Horizon oil spill, for more information on this.

Agatha the 6th deadliest Eastern Pacific storm on record
Central America's Tropical Storm Agatha is now the 6th deadliest Eastern Pacific tropical cyclones on record. Agatha was a tropical storm for just 12 hours, making landfall Saturday on the Pacific coast of Guatemala as a 45 mph tropical storm. However, the storm brought huge amounts of rain--as much as 36 inches--to the high mountains of Guatemala. So far, flooding and landslides have killed at least 123 people in Guatemala, with 59 others missing. The storm also killed 9 in neighboring El Salvador, and 14 in Honduras.


Figure 4. Journey to the center of the Earth: a massive sinkhole 200 feet (60 meters) deep opened up in the capital, Guatemala City, after heavy rains from Tropical Storm Agatha. How are they going to fix this hole? Wow! It doesn't even look real.

Guatemala's worst flooding disaster in recent history was due to Hurricane Stan of 2005, which killed 1,513. The deadliest Eastern Pacific tropical cyclone on record for Guatemala was Hurricane Paul of 1982, which made landfall in Guatemala as a tropical depression. Flooding from Paul's rains killed 620 people in Guatemala.

Oil spill update
Light onshore winds out of the south to southwest are expected to blow over the northern Gulf of Mexico all week, resulting increased threats of oil to the Alabama and Mississippi barrier islands, according to the latest trajectory forecasts from NOAA. These persistent southwesterly winds will likely bring oil very close to the Florida Panhandle by Saturday.

Oil spill resources
My post, What a hurricane would do the Deepwater Horizon oil spill
My post Wednesday with answers to some of the common questions I get about the spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
Gulf Oil Blog from the UGA Department of Marine Sciences
NOAA trajectory forecasts
Deepwater Horizon Unified Command web site
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Surface current forecasts from NOAA's HYCOM model
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Join the "Hurricane Haven" with Dr. Jeff Masters: a new Internet radio show
Today, I'll be experimenting with a live 1-hour Internet radio show called "Hurricane Haven." The show will be aired at 4pm EDT on Tuesdays during hurricane season. Listeners will be able to call in and ask questions. Some topics I'll cover on the first show:

1) What's going on in the tropics right now
2) Preview of the coming hurricane season
3) How a hurricane might affect the oil spill
4) How the oil spill might affect a hurricane
5) New advancements in hurricane science presented at this month's AMS Conference on Hurricanes and Tropical Meteorology
6) Haiti's vulnerability to a hurricane this season

I hope you can tune in to the broadcast, which will be at http://www.wunderground.com/wxradio/wubroadcast.h tml. If not, the show will be recorded and stored as a podcast.

Portlight receives a major grant to fund U.S. disaster relief work
The Christopher and Dana Reeve Foundation has announced today that it is awarding a Quality of Life Grant in the amount of $21,500 to Portlight Strategies, Inc. The grant will fund a ready-to-deploy container specifically outfitted to serve the immediate needs of people with disabilities in the aftermath of hurricanes and other domestic natural disasters. To read more about this award, check out the Portlight blog. Congratulations, Portlight team!

Portlight continues its Haiti response
Ready or not, the rainy season is here for Haiti. Portlight has done a tremendous amount to help the Haitians get ready for the upcoming hurricane season, as detailed in the Haitian Relief Recap blog post made last week. Please visit the Portlight.org web site or the Portlight blog to learn more and to donate to Portlight's efforts in Haiti.


Figure 5. A portion of the 30,000 pounds of rice donated to Haitian earthquake victims by Portlight earlier this month, shipped via the schooner Halie and Mathew.

I'll be back Wednesday afternoon with an analysis of the new Colorado State University hurricane forecast issued by Phil Klotzbach and Bill Gray, due out on June 2.

Jeff Masters

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Quoting kmanhurricaneman:
kmanislander- I agree it is moving ENE and we will get some rain from it i doubt very much though as it seems to start moving at a good clip.


I'll settle for dew now !
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kmanislander- I agree it is moving ENE and we will get some rain from it i doubt very much though as it seems to start moving at a good clip.
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Hey Floodman

still matching whits with the unarmed I see. Not very sporting. Tut tut
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CIMSS has a nice portal for Phet as it does for all systems

Nice visible loops too

Link

Just click on animation option in the upper left of the page to show a loop of the system
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the blow up of convection apparent on sat,is low level convergence in the form of a South-North Band of precip pretty far removed from the center,IMO...this area w/dispate in a few hrs......
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Let us know how the radio show goes. I'm stuck at work and can't really pay attention.
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417. RM706
http://www.wunderground.com/wxradio/wubroadcast.html
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Quoting LoneStarWeather:

There's a reason they retired her name, even though she was never more than a TS. That was one wild storm!


Ewww... Allison... Allison was what made MANY people realize... you don't need a hurricane to cause widespread disaster. :-(

We had some awful Allison-related deaths here in Houston. :-(
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414. RM706
Dr. Masters is on the show now!
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Quoting ShenValleyFlyFish:


They couldn't possibly hate us because our military and money have propped up some of the most corrupt governments in the world while our corporations have sucked out most of their countries wealth and we have got fat and unhappy and they are still poor as church mice. No that would make sense. Can't be that. People not like us got no sense.


It's because American troops have been deployed in Muslim countries. If Syria invaded America and set up its millitary in the country, the Americans would get pretty angry at them too right?
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Love the radio show so far.
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Quoting CycloneOz:


I know exactly what that gulf coast heat smells like, too.

Tobacco juice mixed in with arm pit sweat.
WOW, you know my next door neighbor also....LOL
Member Since: February 27, 2010 Posts: 0 Comments: 1125
Afternoon all! See we have 91L out of the remains of Agatha.. conditions aren't terribly favorable for development but it has a chance. This is a very tiny system, so DMIN will hit it early and stronger than most larger systems.. and vice versa for DMAX.
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409. IKE
Memo to whomever(NHC or SSD): Can you please put a floater back on 91L?
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408. skep
I hope that Tropical Cyclone Phet won't be that strong, because right now it still could hit one of the biggest cities in the world - Karachi! This city is just north of the projected path.
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407. RM706
Time for the show .. we have a big audience today! http://www.wunderground.com/wxradio/wubroadcast.html
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Quoting IKE:
Looks like 91L is currently heading toward western Cuba and the Isle of Youth.


if the center truely is under that convection, then it's moving into more favorable conditions for development..
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Quoting unf97:



It is. This from the NHC TWD 2:05 p.m.

...DISCUSSION...

THE GULF OF MEXICO...
MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW COVERS THE AREA THANKS
TO A TROUGH THAT RUNS FROM THE TEXAS/MEXICO BORDER ALONG THE
GULF OF MEXICO COAST...NORTHEASTWARD BEYOND SOUTHEASTERN
LOUISIANA AND THE WESTERN FLORIDA PANHANDLE. MODERATE SHOWERS
AND THUNDERSTORMS COVER THE AREA FROM 23N TO 28N BETWEEN 92W AND
96W. ISOLATED MODERATE SHOWERS ARE IN THE NORTHEASTERN CORNER OF
THE AREA...TO THE NORTH OF 26N TO THE EAST OF 90W. SHOWERS ALSO
ARE INLAND IN SOUTHERN COASTAL SECTIONS OF LOUISIANA...
i did not go looking for anything to read just an observation and comment
Member Since: July 15, 2006 Posts: 178 Comments: 56059
403. IKE
Looks like 91L is currently heading toward western Cuba and the Isle of Youth.
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Kingy, I live 9 miles from Dauphin Island and am on Mobile Bay. I was just outside 20 minutes ago getting my mail and didn't smell anythiing except the heat.
Member Since: February 27, 2010 Posts: 0 Comments: 1125
Quoting CaneWarning:


Is the last part a joke? I sure hope so? If not, no wonder everybody hates Americans.


No, unfortunately I'm afraid it's not...it shows how little Americans know about science and narrow and Xenophobic our collective world view is
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Quoting wunderkidcayman:
guys the COC is NOT near the yucatan peninsula

it is at 19.1N 85.9W moving slowly NE


Are you sure? How do you know? Seems like the COC drifted west from the convection. Its totally observable. Is the COC under the blog of convection??
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398. unf97
Quoting KEEPEROFTHEGATE:
its part of a weak ULL thats over LA i believe



It is. This from the NHC TWD 2:05 p.m.

...DISCUSSION...

THE GULF OF MEXICO...
MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW COVERS THE AREA THANKS
TO A TROUGH THAT RUNS FROM THE TEXAS/MEXICO BORDER ALONG THE
GULF OF MEXICO COAST...NORTHEASTWARD BEYOND SOUTHEASTERN
LOUISIANA AND THE WESTERN FLORIDA PANHANDLE. MODERATE SHOWERS
AND THUNDERSTORMS COVER THE AREA FROM 23N TO 28N BETWEEN 92W AND
96W. ISOLATED MODERATE SHOWERS ARE IN THE NORTHEASTERN CORNER OF
THE AREA...TO THE NORTH OF 26N TO THE EAST OF 90W. SHOWERS ALSO
ARE INLAND IN SOUTHERN COASTAL SECTIONS OF LOUISIANA...
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DMIN is hitting.. it, tends to happen with all systems.. develops a beatiful outflow and organizes during the day, and at night it goes boom.

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Quoting watcher123:
354:


I've read enough of the Koran to know the "Extremists" are actually the real Muslims.

Now CNN won't admit that to you, but anyone who bothers to inform themselves of the truth would know that.

The Crusades was a thousand years ago. It's got nothing to do with me.


I know several Muslims. They are kind people. You can't just paint all Muslims with such a broad brush like you do. I suppose all bloggers should be compared to JFV since after all, we do use the same weather blog as he.
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395. kingy
coast dwellers - with the winds coming from the south is there a stronger oil smell coming from the gulf ??
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I just took a look at 91L and it is definitely on the move. However, the motion looks to be somewhere between ENE and NE, not quite as sharp as NE.

Grand Cayman may catch the Southern edge of the weather as it passes by. We will know tonight !
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Quoting CycloneOz:


Interesting...these flair-ups in high-shear environments...

Same fate that awaits 91L, I predict.


That flare up in the GOM really isn't associated with much of a surface feature though like 91L currently is.
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392. IKE
Slight vorticity now showing up in the western GOM...earlier NAM and GFS had that blob headed NE to ENE....

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guys the COC is NOT near the yucatan peninsula

it is at 19.1N 85.9W moving slowly NE
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Join the "Hurricane Haven" with Dr. Jeff Masters:
a new Internet radio show
Today, I'll be experimenting with a live 1-hour Internet radio show called "Hurricane Haven." The show will be aired at 4pm EDT on Tuesdays during hurricane season.


http://www.wunderground.com/wxradio/wubroadcast.html.
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Quoting IKE:


I'm watching it. I commented on it a few minutes ago. ^-^
its part of a weak ULL thats over LA i believe
Member Since: July 15, 2006 Posts: 178 Comments: 56059
Quoting Stormchaser2007:


May just be a blob, but I'm thinking we might get something here briefly.
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Seriously, this thing is gigantic.



If you could take the farthest west, east, north and south points on Pakistan, form a rectangle using lines parallel to the points' directions, then draw a circle that fit within the rectangle, that's how big this storm is (basically the area of Pakistan, Afghanistan and Nepal combined). 13 degrees tall by longitude, 15 degrees wide by latitude. The main convection is 8 deg lon, 7 deg lat.
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sorry IKE missed it, just stoped in to see whats shaking.
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383. xcool
Hurricane season kickoff show tonight


http://www.hurricanecity.tv
Member Since: September 26, 2009 Posts: 2 Comments: 15684
382. IKE
Quoting kmanhurricaneman:
is any one watching the gulf off the coast of texas is that just demax or is there a circulation happening?


I'm watching it. I commented on it a few minutes ago. ^-^
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is any one watching the gulf off the coast of texas is that just demax or is there a circulation happening?
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Quoting SouthALWX:

A) it's not Muslim's, it's extremists (Im sure they felt the same way when we were slaughtering them in the Crusades...)
B) Enjoy your ban.


They couldn't possibly hate us because our military and money have propped up some of the most corrupt governments in the world while our corporations have sucked out most of their countries wealth and we have got fat and unhappy and they are still poor as church mice. No that would make sense. Can't be that. People not like us got no sense.
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Breaking News: Tar balls and puddles of oil from the Gulf spill reach Alabama's Dauphin Island, residents and researchers say.
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377. kingy
Quoting jojotown:
Some people up north look at woolly caterpillars and predict severity of winter. I count the # of migrating ducklings I see around here to give me a feel for hurricane season. Last year I saw one duckling, this season 12! Let's see what that means!!!


duckling-caster
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INV/91/L
MARK
19.2N/85.7W
Member Since: July 15, 2006 Posts: 178 Comments: 56059
375. xcool
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Issued: Tuesday, June 1, 2010 440 am EDT/340 am CDT

Outlook
This is an updated seasonal forecast and is being updated to increase the number of expected storms and to also try to pin down the areas that are of greatest risk this hurricane season.

Bottom line, it looks like we are in for one hell of a bad hurricane season. I cannot stress this enough!!

ENSO Conditions: The strong El Niño that was observed this past winter has all but disappeared and has been replaced by neutral conditions. It appears that La Nina conditions will develop during the summer and in fact, La Nina conditions may already be developing across the Atlantic Basin.

The current sunspot cycle is something that needs to be looked at as well. Low levels of sunspot activity (like what is occurring right now) is accompanied by a decrease in solar wind activity. There is theory out there that says low sunspot activity is correlated with cloud growth and thus help lower the sea level pressures and favor a cooler ENSO (ie. La Nina).

So, based on this it appears that we are well into neutral ENSO conditions and a La Nina appears to be developing. This La Nina is forecast to become moderate as the hurricane season progresses. La Nina conditions support low sea level pressures and low wind shear values over the Atlantic Basin. This will likely enhance tropical cyclone activity in the Atlantic Basin.

Atlantic Multidecadal Oscillation (AMO): The AMO is basically a long term pattern of variability in sea surface temperatures in the Atlantic Basin. This strongly influences tropical cyclone activity by modifiying sea surface temperatures over the Atlantic.

The AMO is currently warmer than it has been in recent history. The latest monthly AMO value was 0.478°C, which is the fourth warmest value in any month on record. More important to tropical cyclone activity, however, are sea surface temperatures in the tropical Atlantic. Readings in this area are measured by the Tropical North Atlantic (TNA) index. The TNA dataset only goes back to 1950. With that said, both March and April’s values are new records and sea surface temperatures have only increased further during May.

The reason why sea surface temperatures are so warm is because an unusually weak subtropical ridge of high pressure was in place over the tropical Atlantic. This, in turn, reduced trade winds in the tropics and helped to warm the sea surface temperatures.

As we head into the hurricane season, I expect that the easterly ocean currents over the tropical Atlantic will carry the very warm sea surface temperatures westward and cause the Caribbean and Gulf of Mexico to warm further than what has already occurred. Based on this, I expect above to well above average sea surface temperatures in the Caribbean and Gulf of Mexico by the heart of the hurricane season. These very warm sea surface temperatures across the entire tropical Atlantic will be very favorable for tropical cyclone formation since they cause lower sea level pressures and thus causes more convection and fuel for developing tropical cyclones.

Analog Years: I have tried to focus in on just a few years that are a close match to what this hurricane season may be like. They are 1964, 1969, 1995 and 2005. As for potential risk areas, I have attached links that outline each hurricane season of those 4 analog years. A few areas stand out for higher concentration of landfalls during those 4 analog seasons. These areas include eastern North Carolina and the outer banks of North Carolina, south Florida and the northwest Bahamas, the central Gulf coast (from Louisiana to the Florida Panhandle), the Leeward Islands and Virgin Islands and finally the northwest Caribbean, including the Yucatan Peninsula, western Cuba and the Cayman Islands.

This idea for potential threat areas is supported by the forecast summer pattern of a ridge of high pressure over the southeastern United States. This ridge of high pressure will prevent any tropical cyclones from turning out into the open Atlantic once they reach 65 West Longitude and potentially steer these storms right into the Gulf of Mexico.

1964:


1969:


1995:


2005:


Highest Threat Areas For 2010 Hurricane Season:


Based on the very favorable conditions out there this season, I am increasing my projected number of storms/hurricanes/major hurricanes for this year:

18 Named Storms
10 Hurricanes
6 Major Hurricanes

One caveat to my forecast number of storms and hurricanes is that if the wind shear values end up being more favorable for tropical cyclone development and the dry Saharan dust layer is less pronounced than what is being forecast (which both are already forecast to be fairly low during the hurricane season), we may end up with storm numbers in the twenties and may in fact approach the levels seen in 2005.

Sea Surface Temperature Map:


Tropical Cyclone Heat Potential Map:


So, to sum it up, I am looking at a hurricane season coming up that will be extremely active. I expect La Nina conditions throughout the hurricane season. In addition, above average to much above average ocean temperatures and below average sea level pressures point to a potentially extremely active hurricane season with at least two landfalling tropical storms and at least three landfalling hurricanes on the US coastline.

This outlook should be the catalyst to really buckle down and purchase supplies for the hurricane season. A really good website to help you create a plan for the hurricane season is http://www.onestorm.com .

If you haven’t done so already, put together your hurricane survival kit as soon as possible. In addition, please take a close look at your homeowners or renters insurance and ensure that you are properly covered for damages or total loss. Also, if you don’t have flood insurance and live in a hurricane zone, I strongly urge you to consider taking on flood insurance. Your homeowners/renters insurance does not cover for floods caused by storm surge or river flooding and it takes 30 days for the flood insurance to take effect.

2010 Atlantic Tropical Cyclone Names:


Member Since: September 26, 2009 Posts: 2 Comments: 15684
Quoting MrstormX:


So true, I think it has a lot to do with the center of of circulation... as long as it stays near or under the convection it will survive longer.


and deepen.. I remember yesterday as the mid level low and convection was racing to the N/NNE I saw a spin to the south of it, but very weak and likely not completely at the surface.. that spin gave it life.. that's why it is now an invest..

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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