Average hurricane season foreseen by CSU, but TSR predicts an active season

By: Dr. Jeff Masters , 5:01 PM GMT on April 07, 2009

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A near-average Atlantic hurricane season is on tap for 2009, according to the latest seasonal forecast issued today by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). The Klotzbach/Gray team is calling for 12 named storms, 6 hurricanes, and 2 intense hurricanes. An average season has 10-11 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast is a step down from their December forecast, which called for 14 named storms, 7 hurricanes, and 3 intense hurricanes. The new forecast calls for a near-average chance of a major hurricane hitting the U.S., both along the East Coast (32% chance, 31% chance is average) and the Gulf Coast (31% chance, 30% chance is average). The Caribbean is also forecast to have an average risk of a major hurricane.

The forecasters cited several reasons for reducing their forecast from an active season to an average season:

1) Sea surface temperature (SST) anomalies in the tropical Atlantic have cooled considerably since December. In fact, these SST anomalies are at their coolest level since July 1994. Cooler-than-normal waters provide less heat energy for developing hurricanes. In addition, an anomalously cool tropical Atlantic is typically associated with higher sea level pressure values and stronger-than-normal trade winds, indicating a more stable atmosphere with increased levels of vertical wind shear detrimental for hurricanes. Part of the reason for the substantial cooling since December is because a stronger than average Bermuda-Azores High drove strong trade winds. These strong winds acted to evaporate more water from the ocean, cooling it. Higher winds also increase the mixing of cool waters to the surface from below. However, in March, the Bermuda-Azores High weakened. The resulting weaker trade winds may allow SSTs to warm to above average levels by the coming hurricane season, if this weaker Bermuda-Azores High persists.

2) Hurricane activity in the Atlantic is lowest during El Niño years and highest during La Niña or neutral years. The CSU team expects current weak La Niña conditions to transition to neutral and perhaps weak El Niño conditions (50% chance) by this year's hurricane season. April and May are typically the months when the atmosphere will swing between El Niño and La Niña, which makes any seasonal forecasts of hurricane activity during April low-skill. The current computer models used to predict El Niño (Figure 1) mostly favor neutral conditions for the coming hurricane season. These models are primarily based on statistical methods that observe how previous El Niño events have evolved. Three of the newer computer-intensive dynamical models (similar to the GFS model we use to make weather forecasts) do predict an El Niño event by hurricane season. The reliability of all of these models is poor.


Figure 1. Computer model forecasts of El Niño/La Niña made in March. The forecasts that go above the red line at +0.5°C denote El Niño conditions; -0.5°C to +0.5°C denote neutral conditions, and below-0.5°C denote La Niña conditions. Three computer models predict El Niño conditions for hurricane season (ASO, August-September-October). However, most of the models predict neutral conditions. Image credit: Columbia University's IRI.

Analogue years
The CSU team picked five previous years when atmospheric and oceanic conditions were similar in April to what we are seeing this year. Those five years were 2001, featuring Category 4 storms Michelle, which hit Cuba, and Iris, which hit Belize; 1985, which had Category 3 Gloria in New England and Category 3 Elena in the Gulf of Mexico; 1976, which had Category 1 Hurricane Belle in New England; 1968, which had Category 1 Hurricane Gladys north of Tampa; and 1951, which had only one landfalling hurricane, Category 3 Hurricane Charlie in Mexico. The mean activity for these five years was 11 named storms, 7 hurricanes, and 3 intense hurricanes.

How accurate are the April forecasts?
This year's April forecast uses the same formula as last year's April forecast, which did quite well predicting the 2008 hurricane season. Last year's forecast included the statement, "These real-time operational early April forecasts have not shown forecast skill over climatology" during the 13-year period 1995-2007. Unfortunately, this year's forecast neglects to mention this fact. In fact, when looking at Excel spreadsheet of their forecast errors (expressed as a mathematical correlation coefficient, where positive means a skilled forecast, and negative means they did worse than climatology) their April forecasts have had negative skill between 1995-2008. In other words, you would have been better off using climatology than believing their April forecasts.

2009 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.
The British private forecasting firm Tropical Storm Risk, Inc. (TSR), issued their 2009 Atlantic hurricane season forecast yesterday, but they are calling for an active year: 15 named storms, 7.8 hurricanes, and 3.6 intense hurricanes. TSR predicts a 63% chance of an above-average hurricane season, 24% chance of a near-normal season, and only a 13% chance of a below normal season. They give a 63% chance that 2009 will rank in the top third of most active hurricane seasons on record. The April 2009 TSR forecast is virtually identical to their December 2008 forecast, and is also quite close to their April 2008 forecast made for the 2008 hurricane season.

I like how TSR puts their skill level right next to the forecast numbers: 11% skill above chance at forecasting the number of named storms, 9% skill for hurricanes, and 7% skill for intense hurricanes. That's not much better than flipping a coin, but is better than the negative forecast skill of the Klotzbach/Gray April forecasts.

TSR projects that 4.8 named storms will hit the U.S., with 2.1 of these being hurricanes. The averages from the 1950-2008 climatology are 3.2 named storms and 1.5 hurricanes. Their skill in making these April forecasts for U.S. landfalls is 10-15% above chance. In the Lesser Antilles Islands of the Caribbean, TSR projects 1.4 named storms, 0.6 of these being hurricanes. Climatology is 1.1 named storms and 0.5 hurricanes.

TSR cites one main factor for their forecast of an active season: slower than normal trade winds from July - September over the Main Development Region (MDR) for hurricanes over the Atlantic (the region between 10° - 20° N from Central America to Africa, including all of the Caribbean). Trade winds are forecast to be 0.4 meters per second (about 1 mph) slower than average in this region, which would create greater spin for developing storms, and allow the oceans to heat up due to reduced evaporational cooling. TSR forecasts that SSTs will be near average in the MDR during hurricane season, and will not have an enhancing or suppressing effect on hurricane activity.


Figure 2. Accuracy of long-range forecasts of Atlantic hurricane season activity performed by Phil Klotzbach and Bill Gray of Colorado State University (colored squares) and TSR (colored lines). The CSU team's April forecast skill is not plotted, but is less than zero. The skill is measured by the Mean Square Skill Score (MSSS), which looks at the error and squares it, then compares the percent improvement the forecast has over a climatological forecast of 10 named storms, 6 hurricanes, and 2 intense hurricanes. TS=Tropical Storms, H=Hurricanes, IH=Intense Hurricanes, ACE=Accumulated Cyclone Energy, NTC=Net Tropical Cyclone Activity. Image credit: TSR.

Jeff Masters

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Quoting Tazmanian:
hold the phone stop the clocks



40% of a cat 5????



thats a little high dont you think???



i think any where from 2% to 10% ch of a cat 5


We'll have to keep on our toes for that!
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The Masters Golf Tournment Forecast could be an interesting final round.

http://tampaspinsweather.webs.com/apps/blog/show/761024-masters-golf-tourney-forecast-
Member Since: September 2, 2007 Posts: 179 Comments: 20448
Quoting Tazmanian:
hold the phone stop the clocks



40% of a cat 5????



thats a little high dont you think???



i think any where from 2% to 10% ch of a cat 5


I know Taz, although I do have a strange feeling this year for a Hurricane Like dean running through the Caribbean.
Member Since: July 8, 2005 Posts: 259 Comments: 24476
hold the phone stop the clocks



40% of a cat 5????



thats a little high dont you think???



i think any where from 2% to 10% ch of a cat 5
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It'll be in the 80s by Wed., Thurs. this week (and clear) so don't feel too sorry for the spring breakers!
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Quoting Orcasystems:


Spring break.. 55... Florida... those do not compute



don't feel to bad for us,we'll be lucky if we get temps like that next october!!!!...and oh yea,its 70degrees already!!!!!
Member Since: October 5, 2007 Posts: 20 Comments: 4970
the past couple of years,a lot of people put the east coast at a higher risk,which may be true,one gets the feeling we're due.It all comes down to where the A/B high sets up and how strong it gets.
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Quoting CybrTeddy:
I declare it preseason Hurricane forecasting time!
Alright. A few questions, please answer if you wish.
1) When will Ana Form? (my vote 5-28-09)
2) How many storms will there me (my vote 15)
3) How many Hurricanes and Majors do we get? (5/2)
4) What place is most at risk this year? (My vote, Caribbean or East coast)
5) In an off chance, will we see a Category 5 this year? (My vote, possibly and if there is I hope its a fish, and someone was bound to ask the question :D)

I think this years going to prove similar to 2007.

6-15
13
7/3
East Coast
40% of cat 5
Member Since: March 29, 2008 Posts: 0 Comments: 2374
Complete Blog Refresh, with New Weather/CritterCam
Mirror Site
Current Home weather station data.

Daily Area of Interest
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Morning all! Been in hibernation for awhile, but I was just curious to see what was being said about Dr. Gray's forecast.

This coming hurricane season will be my third living in the panhandle, so I don't think I'll be quite as nervous. I've learned a lot from you all and I just wanted to say thanks. About the only thing we can do is be prepared and with all of your suggestions, I think we will be ready for anything that heads our way (if any).

Chuck
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Quoting surfmom:
waking up to 55 degrees -- it's spring break -- all males are hibernating this morning...the sounds of silence and dry,cold air snoring........


Spring break.. 55... Florida... those do not compute
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Morning all,

Yep Doug, I hear you on the much needed winter hiatus. Guess it is about time to start crawling out of blog hibernation though. Another couple of months and it will be time to have eyes glued to the big drinks surrounding us.
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147. CeBas
The season will begin in late June/early July and end in late October.
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G'mornin' all. I took a break for the winter.
Nice to see a bunch of the regulars are still here.

Hey Brian! When we goin to Dewberrys?
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144. WxLogic 6:58 AM CDT on April 08, 2009
And if we don't have enough dust to keep those SST"s down...well, the Atlantic will become a heated pool very quickly
Member Since: March 15, 2008 Posts: 4 Comments: 2492
Good Morning... interesting 2009 forecasts. Unfortunately we'll have to wait until mid to late May in order to get a better feeling on how La Nina behaves. Currently I'm leaning closer to the TSR forecast due to trade wind strength and SSTs on EPAC (Near/Close to S. America coast)... but patience is the key and we'll see by next month.
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41 here this morning-what
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Quoting homelesswanderer:

Yes I watched Faye develope over land this past summer too. I happened upon a weather channel show yesterday and I thought that the guide was mistaken when it read "Tropical Storm Erin rescues" And they were showing Oklahoma. So that brought Erin to mind.

And I'd have to agree SE TX is a lot of water. LOL. I remember watching Humberto out the back door window with rain hitting me as it blew horizontally thru the door. This lightening discussion got me and my husband thinking. There mustve been some lightning during Humberto because we caught glimpses of the trees bending over and scraping the house after the transformers blew.
We didnt think about it at the time though so I can't swear to it. We were a little taken by surprise at that moment. LOL.



Speaking of storms restrengthening over land Hurricane Charlie of 2004 did it in NC. He went from a 70mph tropical storm one advisory back to a 80mph hurricane. The local forecasters thought it was the fact that most everything around there was flooded because of recent heavy rains and he used that.
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Patrap - nice clip from the BigEasy -- Post 125 -- really fascinating -- thanks for highlighting that.. thanks Skye..

wondering whats the dust level looking like this year???? Is Redoubt putting anything or enough in the atmosphere that would affect this side of the planet?
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waking up to 55 degrees -- it's spring break -- all males are hibernating this morning...the sounds of silence and dry,cold air snoring........
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139. HadesGodWyvern (Mod)
Fiji Meteorological Services
Tropical Disturbance Summary
TROPICAL DISTURBANCE FIFTEEN-F
18:00 PM FST April 8 2009
==========================================

At 6:00 AM UTC, Tropical Disturbance 15F (1005 hPa) located at 7.5S 163.0E is reported as moving slowly. Position POOR based on multisatellite infrared imagery with animation and latest Quikscat Pass.

The system lies embedded along a monsoonal trough with low level circulation center difficult to locate. Convection has been persistent for the last 24 hours, but with no real organization. CIMSS indicates the system lies in a low shear environment under a diffluent region. Sea surface temperatures is around 31C. Latest water vapor imagery shows dry air to the southeast. Global models has picked up the system and moves it southwest with little intensification.

POTENTIAL FOR TD15F TO DEVELOP INTO A TROPICAL CYCLONE WITHIN THE NEXT 24 TO 48 HOURS IS LOW.
Member Since: May 24, 2006 Posts: 51 Comments: 46151
138. HadesGodWyvern (Mod)
India Meteorological Department

Tropical Cyclone Outlook (0600z 08APR)
========================================
Convective clouds are seen over parts of southeast Arabian Sea, Comorin Area, southeast Bay of Bengal, and south Andaman Sea

Chief Meteorological Forecast (0000z 08APR)
==============================
A low pressure area is likely to form over south Bay of Bengal around 11th April.
Member Since: May 24, 2006 Posts: 51 Comments: 46151
137. HadesGodWyvern (Mod)
Mauritius Meteorological Services
Tropical Cyclone Warning Number SEVENTEEN
TEMPETE TROPICALE MODEREE JADE
10:00 AM Réunion April 8 2009
=================================

At 6:00 AM UTC, Moderate Tropical Storm Jade (987 hPa) located at 21.9S 49.0E has 10 minute sustained winds of 45 knots with gusts of 65 knots. The storm is reported as moving south at 6 knots.

Dvorak Intensity: T3.5

Gale-Force Winds
=====================
20 NM radius from the center, extending up to 100 NM within the eastern semi-circle

Near Gale-Force Winds
=======================
90 NM radius from the center, extending up to 300 NM in the eastern semi-circle

Forecast and Intensity
======================
12 HRS: 22.6S 48.5E - 40 knots (Tempête Tropicale Moderée)
24 HRS: 23.2S 47.6E - 30 knots (DEPRESSION sur Terre)
48 HRS: 23.2S 47.6E - 25 knots (PERTURBATION Tropicale)
72 HRS: 29.0S 51.6E - 30 knots (Devenant EXTRATROPICAL)

Additional Information
======================
Quikscat data at 0230z confirm maximum winds at 45 kbots. On present fix has been made lat with CC MET-7 imagery.

Under the steering influence of the mid level subtropical ridge located in the east and the rebuild of the subtropical high south to Madagascar, tracks is expected to curve more southwestward within the next 36 hours. On this track, system should make a third landfall tonight within the area of Farafangana.

Friday, a deep mid latitude trough arrives from the southwest and Jade should be embedded within the northwesterly flow ahead of the trough. By that time, system should on a weakening trend within a westerly sheared environment and a possible interaction with land. Extratropical transition could be on the way Saturday as the system will begin to accelerate towards the southeast.
Member Since: May 24, 2006 Posts: 51 Comments: 46151
Quoting homelesswanderer:
In the case of Hurricane Humberto, a moderate Category 1 hurricane produced large amounts of CG lightning upon its landfall. Much of the increase in reflectivity heights can be attributed to the increased frictional convergence at landfall and differences in lightning frequency, location, and polarity can indicate the storm’s convection strength. As the storm continued moving inland on September 13, 2007, the storm’s energy source of warm, moist oceanic fluxes no longer existed, and the storm diminished. This study provides evidence for the relationships between dBZ heights, CG lightning frequencies, and convection.


Ok. I found this from a study on the internet. I'm trying to wrap my very unscientific mind around this very scientific subject. And I'm exhausted. LOL. Good night maybe some of this will make more since to yall.

Link


Something stranger is that last year, Gustav beat out Humberto by 2 hours in terms of TD to Hurricane.
Member Since: July 8, 2005 Posts: 259 Comments: 24476
In the case of Hurricane Humberto, a moderate Category 1 hurricane produced large amounts of CG lightning upon its landfall. Much of the increase in reflectivity heights can be attributed to the increased frictional convergence at landfall and differences in lightning frequency, location, and polarity can indicate the storm’s convection strength. As the storm continued moving inland on September 13, 2007, the storm’s energy source of warm, moist oceanic fluxes no longer existed, and the storm diminished. This study provides evidence for the relationships between dBZ heights, CG lightning frequencies, and convection.


Ok. I found this from a study on the internet. I'm trying to wrap my very unscientific mind around this very scientific subject. And I'm exhausted. LOL. Good night maybe some of this will make more since to yall.

Link
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... i burned the blog rofl!!!
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Fay was one werid storm got more rain from her in 3 hours when she was 500 miles up state then when she first land falled in FLA.
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Quoting atmoaggie:


It could be said that Humberto of 2007 intensified over "land". The quotes are due to the fact that in both S Fla and that piece of SE TX there surface area is as much water as land...pseudolandia (wasn't there an 80s song about it?)

Yes I watched Faye develope over land this past summer too. I happened upon a weather channel show yesterday and I thought that the guide was mistaken when it read "Tropical Storm Erin rescues" And they were showing Oklahoma. So that brought Erin to mind.

And I'd have to agree SE TX is a lot of water. LOL. I remember watching Humberto out the back door window with rain hitting me as it blew horizontally thru the door. This lightening discussion got me and my husband thinking. There mustve been some lightning during Humberto because we caught glimpses of the trees bending over and scraping the house after the transformers blew.
We didnt think about it at the time though so I can't swear to it. We were a little taken by surprise at that moment. LOL.
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Great stuff tonight all... still reading up! :)
Member Since: September 9, 2008 Posts: 6 Comments: 3414
Quoting atmoaggie:


It could be said that Humberto of 2007 intensified over "land". The quotes are due to the fact that in both S Fla and that piece of SE TX there surface area is as much water as land...pseudolandia (wasn't there an 80s song about it?)


True.
Member Since: September 9, 2008 Posts: 6 Comments: 3414
Hey! We're talking about hurricane season again. Whoo hoo. Florida really needs rain. Hurricanes bring rain and so do tropical storms, which are of course better because they bring less destruction...Right now, we're in danger of explosive wildfires. Wind is up, humidity down and the vegetation is very dry.
What impressed me last year was how the landfalls were predicted as if the meterologists were air traffic comptrollers (?controllers?), guiding a plane in for a landing! The only difference was, they were predicting the land fall of a hurricane, not planning it! The biggest surprise last year was Galveston. Could have been an incredible disaster on the barrier island. I do not know to this day the number of people lost, nor why there weren't more!
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Quoting Seastep:


I watched Faye live, as many did, form her first eye... overland.

Extremely rare, if not unique, though.


It could be said that Humberto of 2007 intensified over "land". The quotes are due to the fact that in both S Fla and that piece of SE TX there surface area is as much water as land...pseudolandia (wasn't there an 80s song about it?)
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Quoting homelesswanderer:
Was that a Hurricane? In Oklahoma?
Tropical Storm Erin May Have Become A Hurricane ... Deep Inland

Or to quote the great Jeff Masters, perhaps Erin was a "Thingamabobbercane"!

a href="http://www.thedailygreen.com/environmental-news/blogs/hurricanes-storms/oklahoma-
cyclone-55041201" target="_blank">Link

LOL. I know they don't redevelope over land just thought this was interesting.


I watched Faye live, as many did, form her first eye... overland.

Extremely rare, if not unique, though.
Member Since: September 9, 2008 Posts: 6 Comments: 3414
WWLLN Five Day Average Density (click for enlarged Image)
Member Since: July 3, 2005 Posts: 426 Comments: 129093
Quoting Skyepony:
I've got to agree with Patrap & the research about the lightning. Oz~ Check out this site. Watch the lightning around the world. There certainly is a corilation. What could be studied more is the type if they can tell it. Definately more frequent toward the center. I've noticed when one is deepning quick like Katrina exiting FL far from center is infrequent but really powerful, ground shaking for a long time, deadly cloud to ground. Lightning pretty much dies off about as soon as it's feeling the effects of any land, cool SST or shear that is hindering it.

The research about the dust & volcanos controling SST by 70%, so being the big factor for hurricanes... 2005 was pretty dusty & hot. They dismiss it as a low dust year & it wasn't. Here's a bit from other research..

For the 2005 hurricane season, which broke records in the Atlantic, however, dust activity was moderate, indicating yet another level of potential complexity to the dust-hurricane interactions, which the researchers are continuing to investigate, Evan says. During that year%u2019s hurricane season, the researchers noted an increase in dust from the African coast, and a dearth of hurricanes forming in the middle of the Atlantic. Instead, they %u201Ckind of got pushed closer to the United States,%u201D he says. Therefore, an indirect effect may also occur, in which the dust may dampen storm formation in the middle Atlantic, but not prevent them from forming farther west.


Light reading and good stuff from skyepony.

Member Since: July 3, 2005 Posts: 426 Comments: 129093
Quoting Patrap:
Heres a decent article on the 2005 canes and the Lightning observed and recorded.

Hurricanes of 2005 were filled with mysterious lightning

The boom of thunder and crackle of lightning generally mean one thing: a storm is coming. Curiously, though, the biggest storms of all, hurricanes, are notoriously lacking in lightning. Hurricanes blow, they rain, they flood, but seldom do they crackle.

Surprise: During the record-setting hurricane season of 2005 three of the most powerful storms--Rita, Katrina, and Emily--did have lightning, lots of it. And researchers would like to know why.

Richard Blakeslee of the Global Hydrology and Climate Center (GHCC) in Huntsville, Alabama, was one of a team of scientists who explored Hurricane Emily using NASA's ER-2 aircraft, a research version of the famous U-2 spy plane. Flying high above the storm, they noted frequent lightning in the cylindrical wall of clouds surrounding the hurricane's eye. Both cloud-to-cloud and cloud-to-ground lightning were present, "a few flashes per minute," says Blakeslee.


No mention of Wilma? The most intense hurricane ever recorded?

Dead end imo. Grasping at straws. Should work on other research on the matter as it is by far the least known. I'm with oz on this one... spend the money elsewhere.

DISCLAIMER: Rights are reserved to change opinion upon further research as this is the first I have heard of this. ;)
Member Since: September 9, 2008 Posts: 6 Comments: 3414
123. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Wellington
Gale Warning
12:00 PM NZST April 8 2009
===================================

LOW [995 HPA] FORMER CYCLONE LIN, NEAR 35S 163W MOVING EAST 10KT.
Member Since: May 24, 2006 Posts: 51 Comments: 46151
122. HadesGodWyvern (Mod)
Fiji Meteorological Services
Tropical Disturbance Summary
9:00 AM FST April 8 2009
==========================================

At 21:00 PM UTC, Tropical Disturbance [1005 hPa] located at 7.0S 163.0E is reported as moving slowly. Position POOR based on multispectral infrared/visible imagery with animation.

The system lies embedded along a monsoonal trough with low level circulation center difficult to locate. Convection has been persistent for the last 24 hours, but with no real organization. CIMSS indicates the system lies in a low shear environment under a diffluent region. Sea surface temperature around the area is 31C. Latest water vapor imagery shows dry air to the southeas.

Global models has picked up the system and movs it southwest with little intensification.

POTENTIAL FOR TD TO DEVELOP INTO A TROPICAL CYCLONE WITHIN THE NEXT 24 TO 48 HOURS IS LOW.

Member Since: May 24, 2006 Posts: 51 Comments: 46151
121. HadesGodWyvern (Mod)
Mauritius Meteorological Services
Tropical Cyclone Warning Number SIXTEEN
TEMPETE TROPICALE MODEREE JADE
4:00 AM Réunion April 8 2009
=================================

At 0:00 AM UTC, Moderate Tropical Storm Jade (987 hPa) located at 21.4S 48.7E has 10 minute sustained winds of 45 knots with gusts of 65 knots. The storm is reported as moving south-southwest at 7 knots.

Dvorak Intensity: T3.5

Gale-Force Winds
=====================
20 NM radius from the center, extending up to 40 NM in the southwestern quadrant and up to 100 NM within the eastern semi-circle

Near Gale-Force Winds
=======================
60 NM radius from the center, extending up to 140 NM in the northeastern quadrant and up to 210 NM in the southeastern quadrant

Forecast and Intensity
======================
12 HRS: 22.9S 47.8E - 40 knots (DEPRESSION sur Terre)
24 HRS: 22.9S 47.8E - 30 knots (DEPRESSION sur Terre)
48 HRS: 24.3S 47.5E - 25 knots (PERTURBATION Tropicale)
72 HRS: 27.3S 51.3E - 30 knots (Devenant EXTRATROPICAL)

Additional Information
======================
Convection wrapped 0.8 on LOG10 spiral. Lower accuracy on present fix that has been made mainly with infrared MET-7 imagery. Under the steering influence of the mid level subtropical ridge located in the east. The rebuild of the subtropical highs south to Madagascar, tracks has taken a more south-southwesterly component within the next 36 hours. On this track, system should make a third landfall this evening or later tonight within the area between Manajary and Farafangana or stay close to the coastal areas of southeast Madagascar. Friday, a deep mid-latitude trough arrives from the southwest and Jade should be embedded within the northwesterly flow ahead of the trough. By that time, system should on a weakening trend within a westerly sheared environment and a possible interaction with land. Extratropical transition could be on the way Saturday as the system begins to accelerate towards the southeast. Present track forecast is based on a global consensus of all available NWP models from the 1200z run that shows some quite good agreement for the general philosophy. However there is still some spread and the outlier one is the UKMET that brings the system eastwards Friday. At this time and according to all the scenario shown by the ECMWF ensemble prediction system, the UKMO solution seems rather unlikely.
Member Since: May 24, 2006 Posts: 51 Comments: 46151
Ossqss - I don't know where you get your data. My source is a combination of Janssen's data through end of 2008 = 510 days; plus the count from NOAA's Space Weather Prediction Center for all of 2009. Jan - Mar = 77 days plus what it shows for this month so far = 7,
so 594 now. The differences between our respective count is pretty insignificant in the long run.
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Yeah..its a Bad day when Bad things have to happen to Good people..
This is the House as it was in 89,in the Movie. The Big Easy.

Cajun Style,cher..

Itsa all gone now..like a faded memory.

Now the New Floodgate and Pumps sit there.
Daring mother nature.

Member Since: July 3, 2005 Posts: 426 Comments: 129093
Pat that picture speaks for itself.
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Looking at atmo's graph and remembering back to that time.Evening,dusk..August 28th 2005
I had a VHS tape running in the VCR and will have to look at the Local radar but something does stand out in mind from that Sunset,around 8pm.

First of all,most all were gone from Bucktown and Metairie. That stood out.
But looking Southeast,a Big Line of t-storms,..low enough on the Horizon..with that eerie Kinda Between CLoud embedded Flashing,was swirling in towards the City...it was the First Rain Band,well ahead of the Eyewall by 9-10 hours almost.

It was kinda then ya knew something was different about this one.

Way off on the Horizon to the Southeast,was the Curving Tower of Katrina's Cirrus top.
Was so Big and far way. And that low angle light from Dusk was hitting it.

Chill's I tell ya man,frigging willies for sure..then went in to see radar and Sat pics.

More chills.

Even the dog was squirrely.





Bruning House Remnants
Bucktown, Louisiana

This is all that is left of a once beautiful, century old white southern-style house with wrap around porches that sat on this peninsula on Lake Pontchartrain. It had survived many big hurricanes but none like Katrina. It was shown in the movie "The Big Easy" and was occupied by a fourth generation of the Bruning family who had a famous seafood restaurant nearby. The restaurant also became treasures of the swift, destructive waters of Katrina.







Member Since: July 3, 2005 Posts: 426 Comments: 129093
NHC is doing some work with lightning:






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A lesson for anyone with trollish tendancies...

Social Networking: How To Behave On An Internet Forum
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what's up everyone,lot-o-wind today in sarasota,there were waves reported to 11ft offshore of my area and thats huge for my neck of the woods!!!!!!...I've also started a local sarasota-suncoast weather chat/tweet on twitter.com,all are welcome and it will be a will provide a wealth of info as the suncoasts #1 source of info for the TC season...sign up its easy and stop by twitter.com and tweet me at twitter.com/sarasotaweather,I'm just getting started and this could help alot of locals when storms threaten the suncoast......
Member Since: October 5, 2007 Posts: 20 Comments: 4970
Little lightning in a cane is the norm. Most of it anywhere near the eyewall occurs in intensifying portions. And usually no where near the flash rate of your average t-storm.

Lots of it all around is the anomaly, which is why Pat found articles that say things like: "during the record-setting hurricane season of 2005 three of the most powerful storms--Rita, Katrina, and Emily--did have lightning, lots of it. And researchers would like to know why."

During Katrina's landfall, there was almost none, but the rainbands well ahead of the storm (24 hours before landfall) clearly had enough convection. Here is a home-brew plot of it:


(white is within the previous 20 minutes through orange being up to 100 minute before the time stamp)
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Ok, I can take a hint. You must have seen my class pic. L8R Back to work

Member Since: June 12, 2005 Posts: 6 Comments: 8186
111. Skyepony (Mod)
I've got to agree with Patrap & the research about the lightning. Oz~ Check out this site. Watch the lightning around the world. There certainly is a corilation. What could be studied more is the type if they can tell it. Definately more frequent toward the center. I've noticed when one is deepning quick like Katrina exiting FL far from center is infrequent but really powerful, ground shaking for a long time, deadly cloud to ground. Lightning pretty much dies off about as soon as it's feeling the effects of any land, cool SST or shear that is hindering it.

The research about the dust & volcanos controling SST by 70%, so being the big factor for hurricanes... 2005 was pretty dusty & hot. They dismiss it as a low dust year & it wasn't. Here's a bit from other research..

For the 2005 hurricane season, which broke records in the Atlantic, however, dust activity was moderate, indicating yet another level of potential complexity to the dust-hurricane interactions, which the researchers are continuing to investigate, Evan says. During that year%u2019s hurricane season, the researchers noted an increase in dust from the African coast, and a dearth of hurricanes forming in the middle of the Atlantic. Instead, they %u201Ckind of got pushed closer to the United States,%u201D he says. Therefore, an indirect effect may also occur, in which the dust may dampen storm formation in the middle Atlantic, but not prevent them from forming farther west.
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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.