First tropical wave of the year; Postcards V: Hurricane warning probabilities

By: Dr. Jeff Masters , 8:44 PM GMT on May 02, 2008

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The first respectable tropical wave of the year rolled off the coast of Africa into the tropical Atlantic today. While sea surface temperatures are too cold this time of year to support development of this tropical wave, today's event does serve as a reminder that hurricane season begins in just one month. Hurricane season in the Eastern Pacific begins May 15, and tropical waves such as this one sometimes serve as the nucleus for May tropical storms, once they cross Central America and enter the Eastern Pacific.


Figure 1. Visible satellite image from 12pm EDT May 2, 2008, showing the year's first African tropical wave. Image credit: Navy research lab, Monterey.

Hurricane conference news
The 28th Conference on Hurricanes and Tropical Meteorology in Orlando is over. A final postcard from the conference is below, and next week, I'll write some long letters about some of the presentations, focusing the hurricanes/global warming debate.

Hurricane warning probabilities
Hurricane specialist Michelle Mainelli of the National Hurricane Center evaluated the usefulness of NHC's new hurricane wind probabilities product. The product, which was developed via funding from the immensely valuable Joint Hurricane Testbed research project, provides users with information regarding the chances of experiencing winds of tropical storm force and hurricane force at specific locations within the five-day forecast period. They also indicate, in probabilistic terms, the range of possibilities regarding when these wind conditions could begin at specific locations (an important factor in the timing of evacuation orders). While these products are primarily intended for use by emergency managers (for decision-making) and the media (for communication of risk and uncertainty), the availability of the products via the NHC website makes it possible for anyone in the general public to use them for their own decision-making.



One of the significant challenges with the probabilities thus far has been relating them to coastal watches and warnings issued by the NHC. A hurricane watch is issued when hurricane conditions are possible within the watch area, generally within 36 hours. A hurricane warning is issued when hurricane conditions are expected within the warning area, generally within 24 hours (or less in some cases). Between 2000-2006, an area of coast under a hurricane watch actually received hurricane-force winds about 20% of the time, while areas under a hurricane warning got hurricane force winds 25% of the time. Mainelli's research shows that at the first issuance of a watch or warning, the new wind probability product typically gives a 10% chance of hurricane force winds impacting the end points of the watch/warning area. These probabilities increase to 32% at the center of the warning area. Her research will be used to help develop an automatic technique that will recommend to NHC forecasters exactly where to place their watches and warnings.

What's your forecast?
For those of you who have a hunch about how many tropical storms and hurricanes we'll see this year, you can log your forecast as part of our first ever "Wundercast" competition. It's a friendly competition between weather enthusiasts to determine the best of the best in weather forecasting. Don't worry if you do not have any experience in forecasting, learn from Weather Underground meteorologist--as well as experienced website community members--to become an expert forecaster. It's free, and you can sign up at http://www.wunderground.com/wundercast/. The first forecast day is Tuesday, May 13, and competitors will be forecasting for San Francisco, California for the first two weeks. Thereafter, you'll be asked to forecast for Omaha, Seattle, Philadelphia, and Miami.

Jeff Masters

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382. FLWeatherFreak91
4:12 PM GMT on May 04, 2008
Again I find myself scouring past Hurricane records to figure out why Hurricanes rarely hit Tampa. It seems the west coast of Florida is situated right between three meteorological 'scenarios':

1) A high pressure system situated in the SE keeps the storm barely to the south of Tampa (wilma).

2) A front will steer the storm east quicker impeding its northern progression (Charley), or

3) A high pressure over the Atlantic will push the Storm directly north to la, ms, or panhandle...
Member Since: December 1, 2006 Posts: 2 Comments: 3619
381. catastropheadjuster
4:04 PM GMT on May 04, 2008
New Blog
Member Since: August 24, 2006 Posts: 21 Comments: 3652
380. atmoaggie
4:00 PM GMT on May 04, 2008
Hey SJ, Pat.

Can you guys imagine if Miami got hit by a Katrina? I don't mean Homestead, but downtown Miami. And I don't mean a quick developing, fairly small diameter Andrew, but a mature, surge-pushing monster. Of course, the lack of a continental shelf off Miami will make it different.

This is one place I've seen that is in a real state of denial about it's vulnerability.
Member Since: August 16, 2007 Posts: 6 Comments: 12461
379. ycd0108
3:59 PM GMT on May 04, 2008
Butterfly flaps it's wings
News coming out (slowly) from Myanmar reminds me of the first reports from Acheh earthquake/tsunami.
I've never been to Burma but I have been to Mae Hong Son which is now under flash flood warning due to Nargis. The Wats (churches) are generally built on the highest points of land if there happens to be such in the area. Mae Hong Son will be OK because it has some topographical relief. Chaing Mae on the other hand (also under flash flood alert) is fairly flat - if I was in that area I'd head for Doy Inthanon - one of the highest points in Thailand
Member Since: January 1, 2008 Posts: 174 Comments: 4586
378. catastropheadjuster
3:50 PM GMT on May 04, 2008
I will do that. I enjoyed listening to it.
sheri
Member Since: August 24, 2006 Posts: 21 Comments: 3652
377. Patrap
3:46 PM GMT on May 04, 2008
That Phoenix area Station 1480kphx has been a real listening post for many here in the Katrina impact zone..

They share the real stories and info. Not just media mainstream fluff.

Give them a call one morning and share your story catastropheadjuster.
Member Since: July 3, 2005 Posts: 420 Comments: 127512
376. catastropheadjuster
3:45 PM GMT on May 04, 2008
I am listening to it.
Member Since: August 24, 2006 Posts: 21 Comments: 3652
375. Tazmanian
3:35 PM GMT on May 04, 2008
The volcano erupted on May 3 near the village of Chaiten, Chile (EPA)



The volcano's eruption is pictured from Ayacara City. It was the first time it had erupted for thousands of years (EPA)



Member Since: May 21, 2006 Posts: 5091 Comments: 114696
374. Patrap
3:32 PM GMT on May 04, 2008
Lurking...am doing Radio interview in Phoenix.
Nova M Radio in Phoenix. Link1480 wkpx
Member Since: July 3, 2005 Posts: 420 Comments: 127512
373. catastropheadjuster
3:30 PM GMT on May 04, 2008
Did everyone leave?
Member Since: August 24, 2006 Posts: 21 Comments: 3652
372. catastropheadjuster
3:29 PM GMT on May 04, 2008
Something else we have new owners of our shop and property they bought the house beside the shop then all the property at the shop they are from Ohio and we have tried to tell them and show them what happened and they say it can't happen agian.There fixing to open a restraunt and bait shop up and all the money they are putting in the restraunt and stuff there gonna loose. If we get a strong south wind water comes up. But we have tried to tell them over and over and they want listen. And on top of that they are a&&holes. They know it all.
Sheri
Member Since: August 24, 2006 Posts: 21 Comments: 3652
371. stormdude77
3:22 PM GMT on May 04, 2008
In case you haven't seen yet...I issued my pre Hurricane season forecast on my blog, see here...
370. catastropheadjuster
3:13 PM GMT on May 04, 2008
H23 Good Morning, I know one thing I will never for get it and everything we lost. We packed up out shop and then still had the house and didn't make it to leave. I will never stay through anything like that agian. I will leave everything behind. Our shop was totally sumerged under water and that river mud really stinks after a couple of days in the sun. And insurance sucks cause they didn't do nothing. At the house we lost the back patio,the garage doors,front door and of course the roof damage and they gave us a check for 2162.00 that's it by time the took the deductable. I know this isn't nothing compared to the folks that lost everything. My point is nothing is worth staying for you can replace everything but your life. Right know I am already prepared for anything that comes this way except for the shop of course you can't pack a boat repair shop up early.
Sheri
Member Since: August 24, 2006 Posts: 21 Comments: 3652
369. hurricane23
3:05 PM GMT on May 04, 2008
Thats exactly what i meant the population which have never experienced a full fledged hurricane continues to grow everyday along our vulnerable coastlines.

www.AdriansWeather.com
Member Since: May 14, 2006 Posts: 8 Comments: 13624
368. Tazmanian
3:03 PM GMT on May 04, 2008
ok pat
Member Since: May 21, 2006 Posts: 5091 Comments: 114696
367. Tazmanian
3:02 PM GMT on May 04, 2008
Formed August 23, 2005
Dissipated August 30, 2005
Highest
winds 175 mph (280 km/h) (1-minute sustained)

Lowest pressure 902 mbar (hPa; 26.65 inHg)
Fatalities 1,836 total
Damage $81.2 billion (2005 USD)
$86 billion (2007 USD)

(Costliest Atlantic hurricane in history)
Member Since: May 21, 2006 Posts: 5091 Comments: 114696
366. Patrap
3:02 PM GMT on May 04, 2008
Katrina Offically at First Landfall near Buras,La was a Cat 4 wind wise.
In the Massive Super CAt 5's Taz..wind driven Cat-5 surge dont go away because the storm winds dropped below Saffir-Simpsons Scale Criteria..at or near landfall.

The SSS dosent relate well to Surge period. Nor impact from it.
Thus the ongoing debate to improve the scale to bring it more in line to surge Potential.
Its ALWAYS surge that causes the deaths and damage on a Large scale.
Always.
Member Since: July 3, 2005 Posts: 420 Comments: 127512
365. StormJunkie
2:59 PM GMT on May 04, 2008
Well said pat, and I can speak the same even 19 years post Hugo.

That said, it is the new folks in an area that really need to hear the stories of past storms as well as the advice of storm veterans. I can see where the transplants would be a pretty big issue in Fla. Help your local transplants understand the severity of these storms. Just my thoughts though.
Member Since: August 17, 2005 Posts: 26 Comments: 15633
364. hurricane23
2:59 PM GMT on May 04, 2008
362. Patrap 10:55 AM EDT on May 04, 2008
I can say this 23. Folks in the Katrina Impact Zone are not swayed by 2 seasons of little or no impacts.

Its always in the back of our minds. With the daily reminders staring us right back in the eyes.

I feel you pat, iam really hoping for a 3rd quite season for us in the U.S.
Member Since: May 14, 2006 Posts: 8 Comments: 13624
363. Tazmanian
2:55 PM GMT on May 04, 2008
and i think Katrina sould have never been a cat 3 at land fall i think it was a cat 5 at land fall


how can a cat 3 do all of that kind of mass that it did???
Member Since: May 21, 2006 Posts: 5091 Comments: 114696
362. Patrap
2:55 PM GMT on May 04, 2008
I can say this 23. Folks in the Katrina Impact Zone are not swayed by 2 seasons of little or no impacts.

Its always in the back of our minds. With the daily reminders staring us right back in the eyes.
Member Since: July 3, 2005 Posts: 420 Comments: 127512
361. Tazmanian
2:54 PM GMT on May 04, 2008
Cyclone kills at least 351 in Myanmar, state-run TV reports By AYE AYE WIN, Associated Press Writer
29 minutes ago



YANGON, Myanmar - A powerful cyclone killed more than 350 people, destroyed thousands of homes and knocked out power in the country's largest city, state-run media said Sunday.





Five regions of the impoverished Southeast Asian country have been declared disaster zones following Tropical Cyclone Nargis, which struck early Saturday with winds of up to 120 mph, the military-run Myaddy television station said.

It said at least 351 people were killed, including 109 who lived on Haing Gyi island off the country's southwest coast. Many of the others died in the low-lying Irrawaddy delta.

In the Irrawaddy's Labutta township, 75 percent of the buildings had collapsed, state television said.

"The Irrawaddy delta was hit extremely hard not only because of the wind and rain but because of the storm surge," said Chris Kaye, the U.N.'s acting humanitarian coordinator in Yangon. "The villages there have reportedly been completely flattened."

The U.N. planned to send teams Monday to assess the damage, he said. Initial assessment efforts have been hampered by roads clogged with debris and downed phone lines, he said.

"At the moment, we have such poor opportunity for communications that I can't really tell you very much," Kaye said.

Witnesses in Yangon said the storm's 120 mph winds blew the roofs off hundreds of houses, damaged hotels, schools and hospitals, and cut electricity to the entire city. The state-owned newspaper New Light of Myanmar reported Sunday that the international airport in Yangon remained shut.

Domestic flights have been diverted to the airport in Mandalay, it said.

"It's a bad situation. Almost all the houses are smashed. People are in a terrible situation," said a U.N. official in Yangon, who requested anonymity because she was not authorized to speak to the media.

"All the roads are blocked. There is no water. There is no electricity," she said.

Yangon residents ventured out Sunday to buy construction materials to repair their homes. The price of gasoline jumped from $2.50 to $10 a gallon on the black market and everything from eggs to construction supplies had tripled, residents said.

Some people expressed anger that the military-led government in Myanmar, also known as Burma, had done little so far to help with the cleanup.

"Where are all those uniformed people who are always ready to beat civilians?" said one man, who refused to be identified for fear of retribution. "They should come out in full force and help clean up the areas and restore electricity."

The Forum for Democracy in Burma and other dissident groups outside of Myanmar called on the international community to provide urgent humanitarian assistance and urged the military junta to allow aid groups to operate freely — something it has been reluctant to do in the past.

"International expertise in dealing with natural disasters is urgently required. The military regime is ill-prepared to deal with the aftermath of the cyclone," said Naing Aung, secretary general of the Thailand-based forum.

Michael Annear, a regional disaster management delegate for the International Federation of the Red Cross in Bangkok, said his agency had teams in Yangon on Sunday distributing shelter kits and other relief supplies.

The cyclone came at a delicate time for Myanmar, which is scheduled to hold a referendum May 10 on the country's military-backed draft constitution. Authorities have not yet said whether they would postpone the vote.

A military-managed national convention was held intermittently for 14 years to lay down guidelines for the country's new constitution.

The new constitution is supposed to be followed in 2010 by a general election. Both votes are elements of a "roadmap to democracy" drawn up by the junta, which has been in power for two decades.

Critics say the draft constitution is designed to cement military power and have urged citizens to vote no.
Member Since: May 21, 2006 Posts: 5091 Comments: 114696
360. hurricane23
2:53 PM GMT on May 04, 2008
358. catastropheadjuster 10:49 AM EDT on May 04, 2008
I hope we never in our lifetime see another Katrina. She really made a name for herself in my opinion. She messed up alot of states with her wrath.
Sheri

Hey Sheri!

Sorry to pass this on but unfortunately it may take another katrina like system to get folks in prep mode after such a low the past 2 seasons.I to hope never to see something of that magnitude go down again.
Member Since: May 14, 2006 Posts: 8 Comments: 13624
359. hurricane23
2:50 PM GMT on May 04, 2008
These deep troughs will keep the season in check as far as the eastern/central atlantic is concerned.No worries out in that area for a while anyway.In a few weeks as ususal 2 dozen invest will begin to pop across the atlantic with more than half of them going POOF.
Member Since: May 14, 2006 Posts: 8 Comments: 13624
358. catastropheadjuster
2:49 PM GMT on May 04, 2008
I hope we never in our lifetime see another Katrina. She really made a name for herself in my opinion. She messed up alot of states with her wrath.
Sheri
Member Since: August 24, 2006 Posts: 21 Comments: 3652
357. Patrap
2:48 PM GMT on May 04, 2008
Its the Battle of Evermore ..

April 25 2008 New Orleans Jazz Festival Robert Plant of Led Zeppelin with Alison Krauss The Battle of Evermore Live! Link

"..The sky is Filled with Good and Bad, that Mortals never know..."
Member Since: July 3, 2005 Posts: 420 Comments: 127512
356. ajcamsmom2
2:44 PM GMT on May 04, 2008
Heading for Church...:)
Check you all later
Member Since: March 15, 2008 Posts: 4 Comments: 2490
355. hurricane23
2:43 PM GMT on May 04, 2008
Some morning thoughts from TPC!

A BROAD TROUGH OF LOW PRES IS EMBEDDED WITHIN THE
ITCZ CENTERED IN THE VICINITY OF 94W. A 00Z QSCAT PASS CONFIRMS
THAT THE E-W ELONGATED CYCLONIC TURNING EVIDENT ON SHORTWAVE IR
IMAGES IS AT THE SFC...HOWEVER ASSOCIATED WINDS ARE LIGHT.
CONVECTION HAS EXPANDED AND DEEPENED OVER THE PAST COUPLE OF
HOURS BUT REMAINS DISORGANIZED. SCATTERED MODERATE IS FROM
9N-12N BETWEEN 92W-95W AND STRETCHED WITHIN THE ITCZ (OUTLINED
ABOVE). MANY OF THE NWP MODELS HAVE THIS WEAK FEATURE
INITIALIZED AND TRACK IT WEST-NORTHWEST AS A WEAK LOW OR OPEN
TROUGH ON THE S PERIPHERY OF A BUILDING LOW-MID LEVEL
RIDGE...AND THIS SCENARIO SEEMS REASONABLE.


Member Since: May 14, 2006 Posts: 8 Comments: 13624
354. Patrap
2:43 PM GMT on May 04, 2008
Lucky wasnt the word for any of that.But being Prepared is the only recourse we all have.

3 weeks and hours now to the Season.

Plenty of time to do now, what everyone will be trying to do in Hours in a Hurricane event.
Member Since: July 3, 2005 Posts: 420 Comments: 127512
353. StormJunkie
2:41 PM GMT on May 04, 2008
No joke pat. I really hate to use a word like lucky with her, but...
Member Since: August 17, 2005 Posts: 26 Comments: 15633
352. Stormchaser2007
2:41 PM GMT on May 04, 2008
Yeah I really hope that my home stays safe in WPB this summer when Im away up in New Jersey.
Member Since: June 9, 2007 Posts: 4 Comments: 15776
351. Patrap
2:39 PM GMT on May 04, 2008
I dont even wanna consider 40 miles west.

Shudder.slinks away cowering
Member Since: July 3, 2005 Posts: 420 Comments: 127512
350. ajcamsmom2
2:38 PM GMT on May 04, 2008
Morning StormJunkie,
Thanks 344. TerraNova
Member Since: March 15, 2008 Posts: 4 Comments: 2490
349. StormJunkie
2:37 PM GMT on May 04, 2008
Hey Sheri, good morning to you as well ☺
Member Since: August 17, 2005 Posts: 26 Comments: 15633
348. StormJunkie
2:37 PM GMT on May 04, 2008
I hear ya Pat! And even with her nasty self y'all got a little lucky. If she had picked a path a little left of what she did...
Member Since: August 17, 2005 Posts: 26 Comments: 15633
347. catastropheadjuster
2:37 PM GMT on May 04, 2008
Good Morning Storm and everyone.
Sheri
Member Since: August 24, 2006 Posts: 21 Comments: 3652
346. hahaguy
2:36 PM GMT on May 04, 2008
i just hope the past two yrs wasnt a wake up call for the calm before the storm for this yr. i live on the east coast of florida and got directly hit by frances jeane and jus hope the BH is setting up to screw me over again
Member Since: August 12, 2007 Posts: 2 Comments: 2838
345. Patrap
2:35 PM GMT on May 04, 2008
Anywhere but here.

Been Doomed and "disastered" once in a Lifetime.




I'll pass on the calamities folks.
Member Since: July 3, 2005 Posts: 420 Comments: 127512
344. TerraNova
2:35 PM GMT on May 04, 2008
OBX stands for Outer Banks (North Carolina).
Member Since: July 30, 2007 Posts: 76 Comments: 4063
343. StormJunkie
2:32 PM GMT on May 04, 2008
Outer Banks, NC

Morning ajs mom :~) Great to see ya
Member Since: August 17, 2005 Posts: 26 Comments: 15633
342. StormJunkie
2:32 PM GMT on May 04, 2008
Good points haha, but at storm would have to approach Tampa at just the wrong angle for the worst case scenario.

Another way overdue spot if you are going by time periods since the last strike is Savannah. My OBX pick is based on the number of canes they have seen in the past years and the fact the past few years have left them unscathed for the most part.
Member Since: August 17, 2005 Posts: 26 Comments: 15633
341. ajcamsmom2
2:31 PM GMT on May 04, 2008
331. StormJunkie 9:01 AM CDT on May 04, 2008
What does OBX stand for???
I really think we will be hit along the TX/LA border...it just seems to have a big bulls eye on it and besides...I live in the area...so, it is doomed
Member Since: March 15, 2008 Posts: 4 Comments: 2490
340. TerraNova
2:27 PM GMT on May 04, 2008
No, no TN, definitely not mistaking you for a wishcaster, and not really even complaining about those that either want to see a cane or think they want to see one. I can relate to wanting to witness and stand in awe of Mother Nature, although it is never something I would wish or want for anyone. Just wanted some clarification, because some could make that same "not looking good" statement and mean the exact opposite. I was pretty sure I knew what you meant though.

LOL; you're welcome. Now that I think of it; "not looking good" can mean two things. Didn't notice at first when i wrote it.

BBL.
Member Since: July 30, 2007 Posts: 76 Comments: 4063
339. hahaguy
2:27 PM GMT on May 04, 2008
another city that is overdue is tampa/st pete. they had a close call with Charly. If a major hurricane would hit their it would be devastating and a enviromental hazard because of all the fuel they have i the bay and not to mention downtown. since tampa bay is like a funnel it would suck up all the water.
Member Since: August 12, 2007 Posts: 2 Comments: 2838
338. StormJunkie
2:21 PM GMT on May 04, 2008
No, no TN, definitely not mistaking you for a wishcaster, and not really even complaining about those that either want to see a cane or think they want to see one. I can relate to wanting to witness and stand in awe of Mother Nature, although it is never something I would wish or want for anyone. Just wanted some clarification, because some could make that same "not looking good" statement and mean the exact opposite. I was pretty sure I knew what you meant though.
Member Since: August 17, 2005 Posts: 26 Comments: 15633
337. vortfix
2:15 PM GMT on May 04, 2008
I don't know if this info has been posted yet or not.....sorry if this is a repeat.


PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE LITTLE ROCK AR
915 PM CDT SAT MAY 3 2008


Severe Weather/Heavy Rain on May 2, 2008
Member Since: October 29, 2007 Posts: 135 Comments: 46068
336. TerraNova
2:14 PM GMT on May 04, 2008
Not looking good for the E coast? Meaning a higher then average probability of landfall?

Got to ask as some folks use terms like the "the greatest season ever" to describe the 05 season. Certainly not a term I would use to describe it.


I mean, looking at the above average SST's and position of the Bermuda high and all. The east coast is at a generally greater risk this year in my opinion (and Dr Gray's) in that probability of landfall is higher.

A greater than average probability would not be good for people like me who live on the east coast, so don't anybody mistake me for a wishcaster (Floyd was bad enough for me, and that didn't even make landfall within a hundred miles of NJ).

"The greatest season ever?" I wouldn't use that either...now that sounds like the words of a wishcaster, or deathcaster, or whatever you call those people...
Member Since: July 30, 2007 Posts: 76 Comments: 4063
335. StormJunkie
2:07 PM GMT on May 04, 2008
Not looking good for the E coast? Meaning a higher then average probability of landfall?

Got to ask as some folks use terms like the "the greatest season ever" to describe the 05 season. Not a term I would use to describe it, but you can see where it could lead to some confusion :~)
Member Since: August 17, 2005 Posts: 26 Comments: 15633
334. StormJunkie
2:04 PM GMT on May 04, 2008
Thanks TN, that Delta sure looks like a nasty place for a landfall. Deltas in that part of the world are almost always littered with farming and fishing communities. That area will be trying to recover for years to come.
Member Since: August 17, 2005 Posts: 26 Comments: 15633
333. TerraNova
2:04 PM GMT on May 04, 2008
OBX is way over due and Fla is just a no brainer ☺

Generally, the way things are shaping out, it's not looking too good for the east coast in general. There are several places that are due or overdue for a hurricane strike. I'll be assessing all of this in my predictions for the year which I'll be releasing on June 1.
Member Since: July 30, 2007 Posts: 76 Comments: 4063
332. TerraNova
2:01 PM GMT on May 04, 2008
Location of landfall and cities hit from the UN (Adobe reader needed).
Member Since: July 30, 2007 Posts: 76 Comments: 4063

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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.