An early start to hurricane season? And, tornado kills 3 in Missouri

By: Dr. Jeff Masters , 2:38 PM GMT on May 14, 2009

The 2009 Atlantic hurricane season may get off to an early start. For the past two days, most of our reliable hurricane forecast models have been predicting the possibility of a subtropical depression forming near Florida or Western Cuba Monday - Thursday next week. An area of disturbed weather associated with a mid- to upper-level trough of low pressure near eastern Cuba and the southeastern Bahama Islands is predicted to slide west-northwest over the next few days. Wind shear over this low, current a prohibitively high 40 knots, is expected to relax to just 10 knots by Monday in the region surrounding Florida. This may allow a disturbance with a surface warm core to develop, according to phase space analyses from Florida State. However, since the upper atmosphere will still be cold, any development of this system will likely be subtropical in nature. If a subtropical storm does form, it may be fairly dry, like Subtropical Storm Andrea of May 2007. This storm ended up fanning fires in Florida, instead of putting them out. Water vapor loops show plenty of dry, continental air in the region, and it will take many days for the atmosphere to moisten enough to support formation of a subtropical depression.


Figure 1. Water vapor image showing moisture from a weak mid- to upper-level low of low pressure over the southeastern Bahama Islands, surrounded by a large area of dry air, and sandwiched between the polar and subtropical jet stream. Image credit: NOAA/SSD.

The GFS and NOGAPS models predict a subtropical depression could form by Tuesday, while the ECMWF shows development later in the week. The latest UKMET model forecast puts development Wednesday or Thursday near Haiti. The area of predicted development is sandwiched in a relatively narrow band of low wind shear between two branches of the jet stream. This is not a typical set-up for formation of a May tropical cyclone. With so much shear and dry air around, I put the probability of a subtropical depression forming next week at about 10%. Any developing system will also have to contend with the arrival Tuesday of a strong upper-level low pressure system that is expected to drop down over the northern Gulf of Mexico. The eventual track of any depression that forms is highly uncertain, and the models support tracks up the U.S. East Coast towards South Carolina, or up the west coast of Florida in the Gulf of Mexico.

Season's first tropical wave arrives
The season's first tropical wave rolled off the coast of Africa yesterday, and is now located near 10N 20W, a few hundred miles off the coast of Africa, according to total precipitable water loops. Mid-May is a fairly typical time for these waves to begin moving across the Atlantic, though they usually don't start developing into tropical depressions until August. Last year was an exception, when Hurricane Bertha formed from a July tropical wave. Wunderground blogger Weather456 has been tracking the date of the first African wave each year since 2004, and these dates have ranged from May 2 to May 21. With Sea Surface Temperatures near average this year in the tropical Atlantic, an early season major hurricane in the eastern Atlantic like Bertha is unlikely.


Figure 2. The line of severe thunderstorms that spawned the Kirksville, MO tornado.

A wild night in Tornado Alley
Northern Missouri took a hard hit by a powerful tornado last night, when a twister passed through Kirksville, killing three people. The tornado flipped cars and damaged 30 - 40 buildings as it tore through the north end of town. The Storm Prediction Center recorded 23 tornado reports across Missouri, Illinois, Oklahoma, and Kansas yesterday.

The Vortex2 field study, the world's largest-ever tornado research project, caught last night's tornado outbreak with its armada of 40 research vehicles and radars. You can read about yesterday's chase on our new featured Vortex2 blog. Our team of University of Michigan students caught some severe thunderstorms, but were forced by darkness to quit before the storms spawned tornadoes.

Portlight/wunderground shirts for sale
The portlight.org disaster relief charity is selling spiffy new shirts sporting the portlight and wunderground logos, to help raise funds for relief operations during the coming hurricane season. I expect that their services will be needed this year, and I encourage you to shell out the $20 to get this fine piece or wunderwear.

I'll have an update on the tropics Friday.
Jeff Masters

V2 Convoy in Canton 2 (Vortex2)
Most of the V2 convoy waited in Canton, OK for initiation.
V2 Convoy in Canton 2

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Log In or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 454 - 404

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog Index

454. IKE
8-14 DAY OUTLOOK FOR MAY 22 - 28 2009

FOR WEEK 2, THE MEAN UPPER AIR CIRCULATION PATTERN DIFFERS LITTLE FROM THE 6-10
PERIOD, FEATURING A TROUGH NEAR THE PACIFIC COAST, WEAK RIDGING NEAR THE CENTER
OF THE CONUS, AND A TROUGH NEAR THE EASTERN GULF OF MEXICO. MODELS DIFFER
CONSIDERABLY ON THE LOCATION AND TRACK OF ANY TROPICAL LOW PRESSURE CENTER THAT
MAY AFFECT FLORIDA OR THE SOUTHEAST, BUT THERE IS A CONSENSUS THAT MOIST FLOW
WILL DOMINATE THE REGION DURING THIS PERIOD. THE MODEL RUNS AVAILABLE TODAY
TEND TO FAVOR EXPANSION OF THE AREA OF ENHANCED ABOVE-MEDIAN RAINFALL WESTWARD
TOWARD THE MISSISSIPPI VALLEY.
Member Since: December 31, 1969 Posts: Comments:
In regards to Accuweather, I think they are developing El Nino too fast. I agree with SSTs not being at levels at past years but 10 storms is too little. 2006 only had those few storms due to a quickly developing El Nino as oppose to 2004 with slowly developing El Nino and that it was most climate models agree on for 2009. El Nino is so funny, that in August of 2004 both NOAA and CSU lowered their forecasts due to a dveloping El Nino which did occur but when the season was over the season saw 15 named storms placing it well above all forecasts. My forecast on Saturday discuss the forecast uncertainties of some factors that give 2009 12-14 named storms.
Member Since: December 31, 1969 Posts: Comments:
Quoting Weather456:
Oh I see, I'm getting 7092 down and 554 up. But Stormchaser2007 that is some crazy speed there.


Yeah im surprised myself. Im running GRLevel2 Analysis now.
Member Since: December 31, 1969 Posts: Comments:
Second time was even better.

Member Since: December 31, 1969 Posts: Comments:
Oh I see, I'm getting 7092 down and 554 up. But Stormchaser2007 that is some crazy speed there.
Member Since: December 31, 1969 Posts: Comments:
Quoting severstorm:
441 darn what are you working with thats fast.


Souped up version of Vista. Pretty impressive setup with 2 monitors.
Member Since: December 31, 1969 Posts: Comments:
446. IKE
....
Member Since: December 31, 1969 Posts: Comments:
Quoting Stormchaser2007:
I cant wait until Accuweather's Hurricane forecast busts. There only calling for 10 storms.


Now im convinced we will have an Active season just because AccuFail says its going to be below average.
Member Since: December 31, 1969 Posts: Comments:
444. IKE
Quoting IKE:


Here's mine....

Download Speed: 8047 kbps (1005.9 KB/sec transfer rate)
Upload Speed: 469 kbps (58.6 KB/sec transfer rate)


I'm watching a MLB game through media player. It slows my computer some.
Member Since: December 31, 1969 Posts: Comments:
441 darn what are you working with thats fast.
Member Since: Posts: Comments:
442. IKE
Quoting Weather456:
Just curious....can anyone tell me their internet speed?

LINK


Here's mine....

Download Speed: 8047 kbps (1005.9 KB/sec transfer rate)
Upload Speed: 469 kbps (58.6 KB/sec transfer rate)
Member Since: December 31, 1969 Posts: Comments:
Quoting Weather456:
Just curious....can anyone tell me their internet speed?

LINK


Download sped was 15,740kbps and upload speed was 5,004kbps.
Member Since: December 31, 1969 Posts: Comments:
Quoting WeatherStudent:


ok, should i make sure i ahce candles and flashlights/


Dude,
you have JFV written all over you.
Member Since: December 31, 1969 Posts: Comments:
456, download was 3758 and upload was 1726 kbps
Member Since: Posts: Comments:
I was to go to Joplin MO tomorrow but now I'm wondering if I should go to OK, KS or go to the coast off GA.....

What do you all think


Taco:0)
Member Since: Posts: Comments:
Just curious....can anyone tell me their internet speed?

LINK
Member Since: December 31, 1969 Posts: Comments:
I cant wait until Accuweather's Hurricane forecast busts. There only calling for 10 storms.
Member Since: December 31, 1969 Posts: Comments:
Quoting CaneAddict:


Your ridiculous..JFV written all over you.


Don't call him ridiculous, he deserves the same rights as you do. However weatherstudent, you need to admit that you are JFV.
Member Since: Posts: Comments:
C OZ, I wish i had the time to chase those storms like you do. Your videos are great. Thanks for taking the videos so i can see what i almost never see.
Member Since: Posts: Comments:
melwerle, ok i will but you must not have me on ignore LOL
Member Since: Posts: Comments:
Please consider those who lurk and are becoming concerned with the potential 10-30% chance of a weak storm in the vicinity of Florida.

Lurkers, you should use this as an incentive to get prepared for the season.

If anything, we will get some much needed rain and preparations in place, not a major hurricane !

Always listen to your local weather professionals first and use the information you get from a blog accordingly. This is not the NHC, but a good place for insight and flavor for sure.

Just my take :)
Member Since: December 31, 1969 Posts: Comments:
or maybe i just have too many people on my "ignore list"

lol
Member Since: Posts: Comments:
blame it on me...
Member Since: Posts: Comments:
Hey All, What killed the blog
Member Since: Posts: Comments:
Quoting charlottefl:
I think I have the polar jet stream running through my house. My roommate has it like a meat locker in here.


Maybe he/she is having a "summer moment" as we call it here...kids in our house complain our food is cold before they can eat it.
Member Since: Posts: Comments:
hey sonny...

;)
Member Since: Posts: Comments:
I think I have the polar jet stream running through my house. My roommate has it like a meat locker in here.
Member Since: Posts: Comments:
Quoting Drakoen:


Daytime heating combined with orographic lift. That will die out. Orographic lift isn't a sustainable process. It acts to take out the moisture and dump it to the surface. As shear dies the interaction with the trough, front, and Gulf Stream may allow for some development.

Ok thanks so much!
Member Since: Posts: Comments:
Quoting Weather456:


LMAOROTFL!

Is that a laugh or someone in pain?


An actual laugh lol
Member Since: Posts: Comments:
Hey Adrian!!! (Would have responded sooner - had to walk the DAWGS)
Member Since: Posts: Comments:
I see most of the models have something developing.
Member Since: Posts: Comments:
Quoting futuremet:
This system will kindle remarkable joy in us eastern Floridians, for it will soothe the xeric atmosphere.

This is how happy we will be



LMAOROTFL!

Is that a laugh or someone in pain?
Member Since: December 31, 1969 Posts: Comments:

What happened to the ensemble for the supposed Ana? And what's with the fish storm the ensembles show?
Member Since: Posts: Comments:
Adrian is pretty much on target with what he said , Tom Terry the local Met in Orlando said the same.
Member Since: Posts: Comments:
Probably something subtropical will happen.
Member Since: Posts: Comments:
hey drak...

:)
Member Since: Posts: Comments:
Quoting floridastorm:
TWC is going to mention the "first tropical storm"


The chances of pure TS are slim but not out of the question.
Member Since: Posts: Comments:
GFS 18z Ensemble
Member Since: December 31, 1969 Posts: Comments:
This system will kindle remarkable joy in us eastern Floridians, for it will soothe the xeric atmosphere.

This is how happy JFV will especially be

Member Since: Posts: Comments:
An animated DGEX link?
Member Since: Posts: Comments:
TWC is going to mention the "first tropical storm"
Member Since: Posts: Comments:
In Orlando the highest sustained wind from Barry was 31mph I believe. At the time, I looked at the records for a bunch of other stations (even on the coast near the point of landfall) and none recorded higher sustained winds than this.
Member Since: Posts: Comments:
Quoting cg2916:
Anyone got a DGEX link?


LINK
Member Since: December 31, 1969 Posts: Comments:
Quoting melwerle:
398.

http://moe.met.fsu.edu/tcgengifs/


Hey Melwerle...
Member Since: Posts: Comments:
000
AXNT20 KNHC 142339
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU MAY 14 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N9W 3N20W 1N30W CROSSING THE
EQUATOR NEAR 32W AND CONTINUING INTO NE BRAZIL NEAR 2S45W.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG THE W
AFRICAN COAST FROM 6N-12N BETWEEN 10W-15W. ELSEWHERE...SCATTERED
MODERATE CONVECTION IS S OF 3N BETWEEN 41W-51W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE ANCHORED IN THE E PACIFIC REGION COVERS MOST OF
THE GULF WITH ONLY A FEW SCATTERED THIN HIGH CLOUDS ADVECTING
ACROSS THE WRN GULF. AN MIDDLE TO UPPER LEVEL SHORTWAVE IS
MOVING ACROSS MISSISSIPPI AND ALONG WITH LOW-LEVEL ATMOSPHERIC
INSTABILITY IS GENERATING SCATTERED SHOWERS AND TSTMS ALONG THE
NE GULF COAST E OF 91W. THIS CONVECTIVE ACTIVITY EXTENDS EWD
ALONG THE FLORIDA PANHANDLE TO OVER THE FLORIDA PENINSULA...
INCLUDING THE IMMEDIATE FLORIDA GULF COAST. ELSEWHERE...FAIR
WEATHER DOMINATES THE REGION WITH SHIP AND BUOY OBSERVATIONS
INDICATING 10-15 KT E TO SE WINDS OVER THE WRN GULF AND LIGHTER
WINDS OVER THE NE GULF DUE TO PROXIMITY OF THE SURFACE RIDGE
AXIS ORIENTED ALONG THE NRN GULF. THIS PATTERN IS EXPECTED TO
REMAIN IN PLACE FOR THE NEXT FEW DAYS UNTIL THE NEXT FRONT
ENTERS THE NW GULF EARLY SUN.

CARIBBEAN SEA...
THE CARIBBEAN IS DOMINATED BY AN UPPER TROUGH THAT EXTENDS FROM
AN UPPER LOW ACROSS THE CENTRAL BAHAMAS NEAR 24N75W. THIS UPPER
TROUGH IS SUPPORTING A SURFACE TROUGH THAT EXTENDS ACROSS THE SE
BAHAMAS TO THE WINDWARD PASSAGE NEAR 19N74W AND CONTINUES TO
GENERATE SCATTERED SHOWERS AND TSTMS N OF 18N BETWEEN 71W-80W.
UPPER DIFFLUENCE LOCATED E OF THE UPPER LOW/TROUGH IS ALSO
PROVIDING SUPPORT FOR SCATTERED SHOWERS N OF 16N BETWEEN
60W-71W. AN UPPER RIDGE IS ANCHORED N OF BRAZIL OVER THE
TROPICAL ATLC NEAR 4N44W AND EXTENDS A UPPER RIDGE NW ACROSS NRN
SOUTH AMERICA. UPPER LEVEL DIFFLUENCE BETWEEN THE UPPER RIDGE
AND TROUGH IS SUPPORTING SCATTERED SHOWERS AND TSTMS ACROSS THE
SW CARIBBEAN S OF 10N TO INLAND OVER PANAMA AND PRODUCING A BAND
OF CIRRUS CLOUDS THAT EXTENDS FROM 10N80W TO OVER PUERTO RICO.
FOR NOW...SURFACE HIGH PRESSURE N OF THE CARIBBEAN IS RESULTING
IN MODERATE TO FRESH ELY TRADE WINDS WHICH ARE FORECAST TO
PERSIST OVER THE NEXT FEW DAYS. POCKETS OF TROPICAL MOISTURE
CONTINUE ADVECTING FROM THE TROPICAL ATLC INTO THE ERN CARIBBEAN
AND COULD RESULT IN ISOLATED LOW LEVEL SHOWERS MAINLY E OF 72W
INCLUDING PORTIONS OF THE LESSER ANTILLES.

ATLANTIC OCEAN...
A SURFACE TROUGH EXTENDS FROM THE NE COAST OF FLORIDA NEAR
DAYTONA BEACH NORTHWARD ALONG THE GEORGIA AND SOUTH CAROLINA
COASTS GENERATING SCATTERED SHOWERS AND TSTMS WITHIN 60 NM OF
THE SE CONUS COASTLINE. ANOTHER AREA OF NUMEROUS SHOWERS WITH
EMBEDDED TSTMS IS LOCATED OFFSHORE N OF 30N BETWEEN 75W-80W. AN
UPPER LEVEL TROUGH EXTENDS FROM AN UPPER LOW NE OF BERMUDA NEAR
36N56W THROUGH 32N58W SW TO 25N64W THEN TO AN UPPER LOW OVER THE
CENTRAL BAHAMAS NEAR 24N75W. THIS UPPER TROUGH SUPPORTS A COLD
FRONT THAT ENTERS THE W/CENTRAL ATLC NEAR 32N53W EXTENDING SW TO
28N63W WHERE IT CONTINUES STATIONARY ALONG 30N69W TO BEYOND
32N73W. THE FRONTAL BOUNDARY IS MOVING INTO AN AREA OF DRIER AND
STABLE AIR AND THUS IS SUPPORTING SCATTERED LOW-LEVEL SHOWERS
WITHIN 60 NM EITHER SIDE OF THE BOUNDARY. A SECOND SURFACE
TROUGH IS IN THE SW ATLC EXTENDING FROM 25N73W ACROSS THE SE
BAHAMAS TO THE WINDWARD PASSAGE AND IS GENERATING SCATTERED
SHOWERS AND ISOLATED TSTMS FROM 17N-25N BETWEEN 70W-78W
INCLUDING HISPANIOLA AND ERN CUBA. THE REMAINDER OF THE ATLC W
OF 60W IS EXPERIENCING FAIR WEATHER AS A SURFACE RIDGE COVERS
THE AREA EXTENDING FROM A 1028 MB HIGH LOCATED S OF THE AZORES
NEAR 35N29W.

$$
HUFFMAN




Member Since: Posts: Comments:
Anyone got a DGEX link?
Member Since: Posts: Comments:

Viewing: 454 - 404

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21Blog Index

Top of Page
Ad Blocker Enabled

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather

JeffMasters's Recent Photos

Mountain wave clouds over Labrador
Mountain wave clouds over Labrador
Mountain wave clouds over Labrador
Labrador ice