Atlantic Tropical Wave/disturbance Thread 2009

[Somerset Squall]

Fantastic image there Cookie, thanks for posting it. Well, any possible development will HAVE to happen sooner rather than later as the system will probably move back inland around Louisiana on Saturday. Convection lingering far to the east over Florida which shows the system isn't gaining any tropical characteristics yet.

[Cookie]

good point,

as the expert out of the 2 of us, how would you rate this becoming ana, out of 100% better or worse then when it became an invest before?

[Somerset Squall]

good point,

as the expert out of the 2 of us, how would you rate this becoming ana, out of 100% better or worse then when it became an invest before?

I'm definitely not an expert Cookie, I have much more to learn, and this situation in particular is quite complex, lol. Even the experts themselves are highly uncertain. Having an extratropical low in the tropics is a nightmare to forecast at the best of times. I'd say it has a slightly better chance of becoming a subtropical or tropical depression this time as the storm already has good structure unlike the last low which this storm absorbed. If shear was low and the air moist then a tropical depression would easily form as waters are just about warm enough. However, shear is not low (it's round 20kts) and the air is dry, so chances are probably not that great overall.

[Cookie]

I don't think much in weather forecasting is easy. as far as calling you an expert will got to look after you ego now haven't we

we be interesting to watch all the same.

Edited May 21, 2009 by cookie

[Somerset Squall]

I don't think much in weather forecasting is easy. as far as calling you an expert will got to look after you ego now haven't

we be interesting to watch all the same.

HAHA

Indeed, a promising start to have this potential so early.

[Cookie]

it back to 90L again?

Edited May 22, 2009 by cookie

[Katherine]

It's turned into a red blob on the NHC's site, with the following special weather outlook report on it:

SATELLITE IMAGERY...RADAR DATA...AND SURFACE OBSERVATIONS INDICATE THAT THE AREA OF LOW PRESSURE CENTERED OVER THE NORTH CENTRAL GULF OF MEXICO ABOUT 150 MILES SOUTH OF MOBILE ALABAMA CONTINUES TO SHOW SOME SIGNS OF ORGANIZATION. ADDITIONAL DEVELOPMENT OF THIS SYSTEM IS POSSIBLE...AND IT COULD BECOME A TROPICAL DEPRESSION AT ANY TIME BEFORE MOVING INLAND OVER THE NORTHERN GULF COAST LATER TODAY. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT IS SCHEDULED TO INVESTIGATE THE LOW LATER TODAY...IF NECESSARY. THERE IS A HIGH CHANCE...GREATER THAN 50 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE BEFORE IT MOVES INLAND WITHIN THE NEXT 24 HOURS. REGARDLESS OF DEVELOPMENT...HEAVY RAINS AND OCCASIONALLY GUSTY WINDS ARE EXPECTED ALONG PORTIONS OF THE NORTHERN GULF COAST THROUGH THE DAY...AND INTERESTS IN THIS AREA SHOULD MONITOR THE PROGRESS OF THE SYSTEM.

[Cookie]

something else developing as well?

another disturbance to keep an eye on?

[Cookie]

next possible invest? outside chance maybe.

000

ABNT20 KNHC 221735

TWOAT

TROPICAL WEATHER OUTLOOK

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

200 PM EDT MON JUN 22 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SHOWERS AND THUNDERSTORMS OVER THE SOUTHWESTERN GULF OF MEXICO AND

BAY OF CAMPECHE ARE ASSOCIATED WITH A WEAK SURFACE TROUGH.

DEVELOPMENT OF THIS SYSTEM...IF ANY...IS EXPECTED TO BE SLOW TO

OCCUR AS THIS SYSTEM MOVES SLOWLY WEST-NORTHWESTWARD. THERE IS A

LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A

TROPICAL CYCLONE DURING THE NEXT 48 HOURS. LOCALLY HEAVY RAINFALL

IS POSSIBLE OVER AREAS OF EAST-CENTRAL AND NORTHEASTERN MEXICO

DURING THE NEXT COUPLE OF DAYS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE

NEXT 48 HOURS.

$$

FORECASTER BLAKE/BRENNAN

[masheeuk]

This must be a record to still with out a named storm in the Atlantic/Caribbean and only on the first named storm in the Pacific and were passed the mid point of June

[Somerset Squall]

This must be a record to still with out a named storm in the Atlantic/Caribbean and only on the first named storm in the Pacific and were passed the mid point of June

It was a record for the East Pacific with Andres not forming until the 20th June when the previous record was the 19th, but we are nowhere near a record for late formation in the Atlantic. I'm not sure what the record is, but it's not unusual to not have a named storm in June, in fact, on average one forms every other year and July is usually quiet too. Take 1992 as an example, a named storm didn't form until the 17th of August, another two months away.

[Cookie]

low potential disturbance Gulf of Mexico

Tropical Weather Outlook

National Oceanic and Atmospheric Administration

Zczc miatwoat all

ttaa00 kNHC ddhhmm

NWS Tropical Prediction Center

National Hurricane Center, Miami, FL

200 pm edt wed jun 24 2009

For the North Atlantic, Caribbean Sea and the Gulf of Mexico:

1. The area of low pressure that was over the western Gulf of Mexico

early this morning has moved inland over northeastern Mexico. There is a low chance, less than 30 percent, of this system becoming a tropical cyclone.

http://www.stormpulse.com/disturbance-1-low-potential-2009

[Cookie]

wave coming off Africa same sort of area as Bertha last year

[Cookie]

http://www.stormpulse.com/disturbance-1-low-potential-2009

Tropical Weather Outlook

National Oceanic and Atmospheric Administration

Zczc miatwoat all

ttaa00 kNHC ddhhmm

NWS Tropical Prediction Center

National Hurricane Center, Miami, FL

200 am edt fri jun 26 2009

For the North Atlantic, Caribbean Sea and the Gulf of Mexico:

1. Showers and thunderstorms associated with a tropical wave in the

western Caribbean Sea have increased between Central America and the Cayman Islands. Development, if any, is expected to be slow to occur as this system moves to the west-northwest at about 10 to 15 mph. There is a low chance, less than 30 percent, of this system becoming a tropical cyclone during the next 48 hours. Locally heavy rain is possible during the next couple of days over areas of Central America from Honduras northward into Belize and the yucatan peninsula of Mexico.

Elsewhere, tropical cyclone formation is not expected during the next 48 hours.

Forecaster blake

[Cookie]

non tropical area of low pressure

Tropical Weather Outlook

National Oceanic and Atmospheric Administration

Zczc miatwoat all

ttaa00 kNHC ddhhmm

NWS Tropical Prediction Center

National Hurricane Center, Miami, FL

200 am edt fri jul 3 2009

For the North Atlantic, Caribbean Sea and the Gulf of Mexico:

1. A non-tropical area of low pressure located about 1100 miles

west-southwest of the azores continues to produce an area of showers and thunderstorms displaced to the east of its low-level center. Further development of this system, if any, will be slow to occur due to unfavorable upper-level winds as it moves generally eastward near 10 mph over the next day or so. There is a low chance, less than 30 percent, of this system becoming a tropical or subtropical cyclone during the next 48 hours.

Elsewhere, tropical cyclone formation is not expected during the next 48 hours.

Forecaster berg

http://www.stormpulse.com/disturbance-1-low-potential-2009

[MR EXTREMES]

non tropical area of low pressure

http://www.stormpulse.com/disturbance-1-low-potential-2009

looking like very very quiet hurricaine season,

infact it makes me wonder how much cooler the tropical alantic is right now something not seen for a fair amount of years be intresting to see if the cooler alantic trend continues.

[kold weather]

Well we finally have a little something to maybe watch. A tropical wave is developing weak-moderate convection in the central Atlantic. There is some slight drift WNW of the convection which may be the first signs that something is trying to seperate from the ITCZ which is a requirement for something to have a shot at developing usually.

ECM and GFS both suggesting there could be some eventual develop down the line though its much to early to get excited about any development. Conditions are ok presently out there, shear is manageable and temps are warm enough, strong divergence is aloft as well which is helping convection to develop. The main issue is though the MDR in El Nino years tend to be rather poor breeding ground since the sub tropical jet tends to be much more active and causes most of the systems to get sheared to death. Therefore I suspect that if this does go on to develop it will do it once its north of 20N, probably between 60-70W, though its too early to make that call.

This has a fair chance of being our next invest IF it does seperate from the ITCZ.

[Cookie]

keep us updated Kold

[kold weather]

Very long time since this has been needed...

Still things seem like they are getting closer to bursting. Two main areas to keep a close eye on. The first is a wave in the central/western Atlantic that is about 24-36hrs away from the Leeward Islands. The wave keeps showing signs of convective development but for now its struggling to keep hold of the deep convection it develops and there doesn't appear to be any circulation at any level. Conditions for now are pretty decent however so if a circulation can get going then it certainly has a shot. Models are very uncertain about the upper conditions ahead of it however. The wave is heading WNW. At the moment there is shear there however it isn't too severe for now. The models appear to be very uncertain about the shear levels ahead of the wave. Some do increase the shear a lot in the Caribbean and that would feed through NE into the region the wave is heading. Others aren't nearly so agressive. For now its got a 24hrs window of development, then uncertainty has to kick in. Conditions may well improve though closer to the SW Atlantic and that maybe where it has the best shot.

The other area that does look very interesting is a wave that is just emerging. There is very likely a surface circulation with this system and a very potent MLC feature that has emerged from Africa in the last 9hrs. Conditions are a little marginal for now though we are reaching the time of year that you can expect waves coming from the Cape Verde regions to stand a chance of developing. The models are suggesting we could see some tropical development and while they are generally developing different waves they are still developing a system in the first place, which means this one does need to be closely watched because development is quite possible, esp in the 36-72hr range.

[Somerset Squall]

African disturbance code orange from NHC:

A LOW PRESSURE AREA ASSOCIATED WITH A TROPICAL WAVE IS PRODUCING AN

AREA OF SHOWERS AND THUNDERSTORMS BETWEEN THE CAPE VERDE ISLANDS

AND THE COAST OF AFRICA. THIS SYSTEM IS SHOWING SOME SIGNS OF

ORGANIZATION AND COULD BECOME A TROPICAL DEPRESSION DURING THE NEXT

COUPLE OF DAYS AS IT MOVES WESTWARD AT 10 TO 15 MPH. THERE IS A

MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS SYSTEM BECOMING A

TROPICAL CYCLONE DURING THE NEXT 48 HOURS. REGARDLESS OF

DEVELOPMENT...SHOWERS AND THUNDERSTORMS WITH LOCALLY GUSTY WINDS

COULD AFFECT PORTIONS OF THE CAPE VERDE ISLANDS OVER THE NEXT

COUPLE OF DAYS.

[Cookie]

African coast.

[Somerset Squall]

Looks as though another decent wave is about to emerge off the coast of Africa. This is more of what you would expect at this time of year.

[Iceberg]

There is a low due to leave African in around 36-48 hrs time which has been pickup by ECM and the last few GFS runs, GFS in particular is keen on developing quite a monster of a storm heading bang into the Caribean in approx 7-9 days time.

This keeps a little lower than 99L and stays in a much more favourable environment for development.

[Iceberg]

The Monster feature is still on GFS this morning(for the 8th run in a row), and has also been on ECM and METO.

This must be a large CAT3 or above IMO shown on GFS in approx 6 days time.

I've got a hunch this will be the Atlantic biggie this year. Conditions once it leaves Africa will be almost perfect for good development.

The track is virtually due west.

Longer range it GFS did have it clattering into CUBA, then North Carolina, but this is 10-12 days down the road.

Edited August 11, 2009 by Iceberg

[chionomaniac]

The Monster feature is still on GFS this morning(for the 8th run in a row), and has also been on ECM and METO.

This must be a large CAT3 or above IMO shown on GFS in approx 6 days time.

I've got a hunch this will be the Atlantic biggie this year. Conditions once it leaves Africa will be almost perfect for good development.

The track is virtually due west.

Longer range it GFS did have it clattering into CUBA, then North Carolina, but this is 10-12 days down the road.

I also think the conditions are more favourable. It is good to see development at a time when it looked like a convective pulse of the MJO would be heading into the area. The forecast suggests the MJO may enter phase 1 in the coming week which along with phase 8 is probably the best phase for Atlantic convective development.

I reckon your hunch could be spot on Iceberg!

Latest development

http://oiswww.eumetsat.org/IPPS/html/MSG/IMAGERY/IR108/COLOR/AMERICA/index.htm

Edited August 11, 2009 by chionomaniac