Grading NHC's Tropical Weather Outlook

By: Dr. Jeff Masters , 4:33 PM GMT on June 06, 2007

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The National Hurricane Center's Tropical Weather Outlook (TWO) is a text-only product that rates the potential of disturbed areas of weather to turn into tropical depressions or tropical storms. The outlooks are issued four times daily, at 5am, 11am, 5pm, and 11pm EDT. I've found them to be an excellent guide to what to watch out for. But how accurate are these outlooks? To find out, Jamie Rhome and Dan Brown, who are two of the hurricane specialists that write the Tropical Weather Outlook, verified the accuracy of all the outlooks issued in 2005 and 2006. They used a three-tiered classification of threat based on the following language appearing in the TWO:

High: "A tropical depression could form tonight or the next day."

Medium: "Some slow development is possible."

Low: "Tropical storm formation is not expected."


These forecasts were then graded by looking at the "best track" database of Atlantic hurricanes and seeing if a tropical depression formed within 48 hours of each TWO issued. The results, shown below, reveal that for the Atlantic in the years 2005 and 2006:

-When the TWO said, "A tropical depression could form tonight of the next day," a depression formed within 48 hours 53% of the time.

-When the TWO said, "Some slow development is possible," a tropical depression formed within 48 hours about 20% of the time.

-When the TWO said, "Tropical storm formation is not expected," a tropical depression formed within 48 hours only 3% of the time.




Figure 1. Verification of the Atlantic and Eastern Pacific Tropical Weather Outlooks issued in 2005 and 2006. Image credit: Jamie Rhome and Dan Brown, National Hurricane Center.

Jeff Masters

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984. Patrap
10:51 AM CDT on June 09, 2007
Water Vapor
GOES-East, METEOSAT-8, & MTSAT
Atlantic Region
Link
Member Since: July 3, 2005 Posts: 426 Comments: 129090
983. Patrap
10:50 AM CDT on June 09, 2007
10-Day Atlantic WAVETRAK Link
Member Since: July 3, 2005 Posts: 426 Comments: 129090
982. seminolesfan
3:41 PM GMT on June 09, 2007
Yeah Adrian that wave looks healthy right now; low shear, good convergence and divergence, and some rotation @ 850mb.
It seems to have good conditions ahead of it until about 40W, but after that it looks like it'll have some SW shear to deal with, IMHO.
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981. Tazmanian
3:44 PM GMT on June 09, 2007
if you ask me JP and 23 that wave you are talking about looks like a TD i no it is not but it looks like one and there dos seen to have a spin to it
Member Since: May 21, 2006 Posts: 5091 Comments: 115351
980. Hellsniper223
3:44 PM GMT on June 09, 2007
Where would the stearing currents have a Capeverde system land right now?
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978. hurricane23
3:25 PM GMT on June 09, 2007
The wave of africa looks impressive and if it holds together we might see something out there.But again thats a big if.
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977. StoryOfTheCane
3:21 PM GMT on June 09, 2007
why arent there any buoys south of Northern Nicaragua?
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976. StoryOfTheCane
3:16 PM GMT on June 09, 2007
got a little Wilma activity

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973. nash28
2:41 PM GMT on June 09, 2007
Good morning everyone. Busy day for me, so I can only pop on for a sec...

The Low being discussed this morning is indeed under very light shear in the area of 5-10kts. SSt's are favorable, but the low does not have an LLC as of yet. Shear is dropping over most of the Carribean, so if it can maintain and increase convection and deepen, it may have a chance. Not sure if we will have 93L or not in the coming days....
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972. Thundercloud01221991
2:38 PM GMT on June 09, 2007
We shall see
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971. sporteguy03
2:37 PM GMT on June 09, 2007
StormW,
That area near Panama might need to be watched under only 5-10 Knots of shear?
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969. leftovers
2:14 PM GMT on June 09, 2007
I am keeping an eye on that wave south of hispanola. Aint much right now barely shows up. It was noticed yesterday by NHC with a 3 mb drop. On a different note hope the best for the shuttle astronaunts. Watching Cnn for updates.
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968. Crisis57
2:17 PM GMT on June 09, 2007
what are everyones thought of the blob off of africa has nice banding
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967. sammywammybamy
9:47 AM EDT on June 09, 2007
Hey does anyone know the death toll from gonu?I am wrighting a blog about this powerfull storm
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965. burroflatsman
1:38 PM GMT on June 09, 2007
Well 53% is a little better than flipping a coin!
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964. Patrap
8:33 AM CDT on June 09, 2007
Mississippi Blues..a slideshow Link
Member Since: July 3, 2005 Posts: 426 Comments: 129090
963. seminolesfan
1:17 PM GMT on June 09, 2007
Your welcome, Gamma.

This time of year it really just depends alot on what the local shear pattern is for each blob.

During the heart of the season the patterns are a little more predictable, but during the early and late season months, with all the different environmental factors lining up on their own time frame, things are much more up in the air (pun intended) as far as development is concerned.
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962. miamihurricane12
1:21 PM GMT on June 09, 2007
Posted By: hurricane23 at 1:21 PM GMT on June 09, 2007.
Not even close to 2005's incredible heat potential that was in place but seems to be catching up to 2006.The water's of the florida coast are quite cool right now.


your right but in the western carribean there is actually spots warmer then in 2005
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961. hurricane23
1:17 PM GMT on June 09, 2007
Not even close to 2005's incredible heat potential that was in place but seems to be catching up to 2006.The water's of the florida coast are quite cool right now.
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960. Patrap
8:18 AM CDT on June 09, 2007
Heat Advisories posted for SE Louisiana and Southern Mississippi.. Ga. and S. Carolina too. Link
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959. seflagamma
9:15 AM AST on June 09, 2007
Thanks Seminolfan for answering my question. we will just keep an eye on the blob!!!!
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957. miamihurricane12
1:01 PM GMT on June 09, 2007
Current Heat Potential



Heat Potential June 9, 2006



Heat Potential June 9, 2005

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956. Patrap
8:08 AM CDT on June 09, 2007
Pets are part of storm plans
They will be evacuated along with people

By Susan Finch
Staff writer

One of the lessons of Hurricane Katrina was the importance of planning for the care of pets during evacuation and other phases of a disaster.

There were haunting stories of people who chose to ride out the hurricane at home rather than abandon their animal companions, in the process risking -- and in some cases losing -- their lives.

Others reluctantly left pets behind in hopes that they'd survive, only to learn later they had died or disappeared, some of them taken by animal rescue teams.

Last fall, in a bid to prevent this kind of thing, state lawmakers ordered a system to evacuate and shelter people with their pets and service animals, such as guide dogs. Major beneficiaries of the program will be elderly, indigent or infirm pet owners who need public help leaving town before a big storm.

Act 615 of 2006, pushed to passage by state Sen. Heulette "Clo" Fontenot, R-Livingston, for the first time allows the state to help evacuate pets, according to veterinarian Dr. Becky Adcock, spokeswoman for the Louisiana State Animal Response Team, a network of volunteer groups working with parish animal control officials to make the new law work.

In another first, pets are now part of the focus of post-disaster search-and-rescue teams, Adcock said. "They can put the animals on the (rescue) boat now," she said.

With Act 615, pet owners who depend on government assistance to leave town ahead of a hurricane can count on state help to evacuate and provide safe places for their animals.

Previously, state shelters accommodated pets of evacuees staying at places where they couldn't bring the animals along.

Housing pets separately

Pet evacuation plans include:

* Picking up people and their pets at designated locations.
* Driving them to central locations where volunteers and public employees will gather information about the owners and tag their pets. Some parishes, such as Plaquemines, have plans to microchip pets.
* Moving pets and their owners to safe shelters out of the hurricane zone -- people in buses and animals in climate-controlled trucks provided by the state to ensure they don't get overheated.

Service animals, like seeing-eye dogs, by law are allowed to stay in shelters with their owners.

But otherwise pets and owners will be housed separately, in facilities close enough together so owners can attend to their animals twice daily.

Pets whose owners aren't well enough to make the daily trips will be temporarily cared for at state prisons by staff and inmates.

Such a huge pet evacuation -- something never before done anywhere in the U.S. -- will require setting up "mega shelters" and running them with lots of volunteer help.

But people like Dr. Carol Foil of the Louisiana State University Veterinary School, one of the leaders of the state's animal response team, said there won't be enough room to shelter every evacuated animal.

"Our main message is anybody who has any of their own resources should make plans for their own animals," Foil said.

City of New Orleans emergency preparedness director Jerry Sneed, among those on the front lines of the operation, agrees, urging pet owners able to afford it to arrange transportation and out-of-town accommodations for themselves and their animals, such as with friends or relatives or in pet-friendly hotels and motels..

"All we want to do is take care of those that have no other means to get out," said Sneed, who expects upwards of 20,000 people to line up for the help. The Louisiana SPCA predicts there will be 10,000 companion animals evacuated from New Orleans alone.

'It has to be done'

Deano Bonano, Jefferson Parish deputy chief administrative officer for emergency operations, predicted that as many as 15,000 residents will seek assisted evacuation. Getting the job done will cost the parish in employee overtime and purchase of equipment to process and tag pets and owners, Bonano said.

Federal reimbursements for those expenditures might be possible if a hurricane hits Jefferson, but the government will pay nothing if a storm doesn't strike, Bonano said. "We may do this three or four times in a season without getting a hurricane, but it has to be done."

Before Katrina, the Louisiana SPCA's message to pet owners was "leave your pet in a safe place," said Heather Rigney, the agency's disaster preparedness coordinator. "Now we realize there is no option but to evacuate one way or another. A lot of people would rather die (than leave their pets behind)," she said. "To them, that's their child, a member of their family."

In Katrina's aftermath, many pet owners came back to find their pets gone, later discovering they'd been rescued by people who took them to other states, where they were given to new owners.

Rigney said this time around, only national animal groups credentialed by the SPCA and carrying identification issued by the state will be allowed to take part in post-storm pet rescues. That way "people can't come in under the guise of kindness and walk off with pets for parts unknown," Rigney said
Member Since: July 3, 2005 Posts: 426 Comments: 129090
955. seminolesfan
1:03 PM GMT on June 09, 2007
groundman-Just like ppl here, I'm sure they watch all kinds of stuff with little chance of development...especially when they're bored. LOL
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954. groundman
1:00 PM GMT on June 09, 2007
Good Morning America or whatever is on this morning just said NHC is watching the ULL down by FL?
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953. miamihurricane12
12:51 PM GMT on June 09, 2007
current SST's



30 day forecast SST's



There is going to be some serious heating going on in the tropical atlantic over the next 30 days
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952. seminolesfan
12:57 PM GMT on June 09, 2007
CGP

Got some greens over in the EPAC this AM!!!
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951. seminolesfan
12:51 PM GMT on June 09, 2007
Posted By: seflagamma at 12:23 PM GMT on June 09, 2007.
Good morning everyone,
just noticed that blob getting very close to the Leeward Islands close to S America? What's up with that? does anyone know???
it really flared up in the past hour.
Gams


That's def got some kind of rotation in the low to mid levels, couldn't get any quickscat conformation of surface winds though. It's not very vertically stacked 'cause the upper level west winds are doing a pretty good job of shearing the convection off to the east of the circulation.


As usual for blobs...just gonna have to wait and see what happens...lol
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950. Patrap
7:52 AM CDT on June 09, 2007
had a hit from Muscat,Oman on my Map Locator..that was neat.

Muscat, Oman Sat, 09 Jun 2007 05:01:46 -0500
Member Since: July 3, 2005 Posts: 426 Comments: 129090
949. hurricane23
12:44 PM GMT on June 09, 2007
State forecaster Ben Nelson- Climate conditions same as in 2004, '05 hurricane seasons...

TALLAHASSEE Florida this year is facing the same climatic conditions that led in 2004-05 to a series of eight hurricanes, which hit or affected the state, a weather expert told state officials Thursday.

State Meteorologist Ben Nelson outlined that scenario for Lt. Gov. Jeff Kottkamp and other members of Gov. Charlie Crist's administration during a briefing on hurricane preparedness for the current season, which began last week.

"We feel very confident that here in Tallahassee at the Capitol we're ready, that our partners back in the counties are ready, and now we just have to make sure the citizens of Florida are ready, too," Kottkamp said.
Warm El Nino currents in the Pacific Ocean that kept last season quiet are not present this year, but Atlantic and Caribbean waters are warmer and that could mean more and stronger storms, Nelson told officials attending the briefing.

The biggest unknown, though, is where steering currents will form off the East Coast, he said. The closer they are to the coast, the worse for Florida.

Nelson said the greatest fear is Miami's vulnerability. Damages could top $150 billion from a direct hit, he said. That's nearly twice as much as the $80 billion estimate for Hurricane Katrina, the nation's most costly storm, according to National Hurricane Center figures.

Officials also discussed similarities in potential vulnerability between New Orleans, which was inundated by Katrina two years ago, and the Tampa Bay area.

"The major difference is our level of response," Kottkamp said. "We're going to respond very quickly and we're going to make sure that everything that can be done from the state down to the counties will be done."

Crist did not attend the briefing. Instead, he was in Miami promoting the state's hurricane preparedness sales tax holiday that continues through Tuesday. It permits people to buy various hurricane supplies, including flashlights, portable radios, fuel containers, batteries, coolers and storm shutters, tax-free.

The governor joined Evelia and Lorenzo Crispo as they bought items for their disaster supply kit at a Home Depot store.
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948. Thunderstorm2
12:39 PM GMT on June 09, 2007
Almost all of the Tropical Waves coming off of Africa will not develop due to the fact they are too clse to the Equator.
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947. hurricane23
12:40 PM GMT on June 09, 2007
.



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946. seminolesfan
12:34 PM GMT on June 09, 2007
Posted By: HurriAndrewFury at 8:37 AM GMT on June 09, 2007.
LMFAO at that fake eye that Tazmanian drew in the center of that Windwards system.


Guess you were wrong about making not-so-smart comments anymore, huh?
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945. miamihurricane12
12:30 PM GMT on June 09, 2007



theres a low pressure in the leeward islands wave



and in the wave coming off the coast of africa

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944. seflagamma
8:23 AM AST on June 09, 2007
Good morning everyone,
just noticed that blob getting very close to the Leeward Islands close to S America? What's up with that? does anyone know???
it really flared up in the past hour.
Gams
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943. Hellsniper223
10:13 AM GMT on June 09, 2007
HurriAndrew... wow... Err... Take a Geography class. Please..?
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942. Thundercloud01221991
10:06 AM GMT on June 09, 2007
That is an Island
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941. Randyman
9:42 AM GMT on June 09, 2007
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
422 AM CDT SAT JUN 9 2007

.LONG TERM...
RIDGING PATTERN TO REDUCE RAIN CHANCES BUT MAINTAIN ABOVE NORMAL
TEMPERATURES THROUGH ABOUT TUESDAY. A TROUGH OF LOW PRESSURE
APPEARS TO DEVELOP ALONG THE NORTH GULF COAST WEDNESDAY AND
THURSDAY WHICH MAY DISRUPT SEA BREEZE GENERATION SOMEWHAT. GFS
GENERATES A STRONG TROPICAL WAVE...PERHAPS SOMETHING MORE
DEVELOPED...FRIDAY NEAR WEST CUBA. GFS HAS A KNACK FOR DEVELOPING
SPURIOUS SYSTEMS...BUT PATTERN SORT OF FAVORS DEVELOPMENT OF AT
LEAST A WAVE AT THAT LATITUDE. WILL MONITOR MODEL TRENDS...BUT
LOCALLY THE RESULT COULD BE A TIGHTENING OF EASTERLY GRADIENT FOR
NEXT WEEK THAT MAY RENEW HIGH TIDE ISSUES IN THE COASTAL SECTIONS.

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939. StormJunkie
4:42 AM GMT on June 09, 2007
I think they are getting ready to show a video of the tank separation during launch.
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938. RL3AO
11:41 PM CDT on June 08, 2007
They will check it out after the dock with the ISS. You know NASA wont let them try re-entry until they are sure there won't be a problem.
937. groundman
4:35 AM GMT on June 09, 2007
Posted By: 4Gaia at 12:33 AM GMT on June 09, 2007.
I know it's not weather related.. but I had a heart attack three weeks ago, and this morning my back went out (two herniated disks) so now i'm on Pain Pills, muscle relaxants, and steroids. Not to mention the heart stuff. I'm about to turn 39 and am in a huge funk because this stuff is only supposed to happen when you get older.. sigh. Anyway blogging here always cheers me up, so.. thanks in advance.


I feel for you 4Gaia, I was a little older than you when I got lyme disease a couple years ago. NEVER really sick before, couldn't be, too busy taking care of everyone else. 95% recovered now I guess but they say you really never recover. Makes you thankful for good health.
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936. StormJunkie
4:28 AM GMT on June 09, 2007
Then that is about the size of the rip, maybe an inch or two larger. It is on the Left/port orbital maneuvering pod...Wherever that is. Thanks for the size info Skye...

Night all. I will pray this all works out well.

...Looks like it is on the upper portion of the shuttle, so it should be away from most of the heat during re-entry.
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935. Skyepony (Mod)
4:29 AM GMT on June 09, 2007
Similiar thing happened on STS-114
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934. Skyepony (Mod)
4:21 AM GMT on June 09, 2007
SJ~I missed it..but most the square tiles are ~6"X6"
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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.