Masters student in tropical meteorology at FSU. Raised in Alaskan blizzards, but drawn toward tropical cyclones by their superior PGF.
By: Levi32 , 4:10 PM GMT on June 06, 2009
Update 1:45pm eastern time: NHC is onboard.
ABNT20 KNHC 061727
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SAT JUN 6 2009
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
CLOUDINESS...SHOWERS...AND THUNDERSTORMS OVER THE SOUTHWESTERN
CARIBBEAN SEA ARE ASSOCIATED WITH A BROAD AND WEAK AREA OF LOW
PRESSURE. ALTHOUGH SIGNIFICANT DEVELOPMENT IS NOT LIKELY AT THIS
TIME...THIS SYSTEM SHOULD BRING LOCALLY HEAVY RAINS TO PORTIONS OF
CENTRAL AMERICA OVER THE NEXT COUPLE OF DAYS. THERE IS A LOW
CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS.
TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS.
Tropical Tidbit from 12:00pm eastern Time 6-6-09:
Not much has changed this morning. A broad area of low pressure spread out across the east Pacific, Central America, and SW Caribbean is still being jumped on by the GFS to turn into a tropical cyclone in the Caribbean within 4 days. A strong area of low-level turning and 850mb vorticity has formed just north of Panama and is moving northwest towards Nicaragua. Wind shear is still around 20 knots in this area, and becomes increasingly stronger within the sub-tropical jet just to the north. There are scattered areas of moderate convection north and south of the low.
I still think the GFS is rushing things forming a TS by 96 hours. The sub-tropical jetstream is still firmly entrenched in the Caribbean, and isn't forecasted to really start retreating to the north until 6 days from now. Until the upper-level environment improves, I expect slow development, if any, of the system near Panama. Land interaction will also be a hindering factor as the low will probably move right over Nicaragua and Honduras during the next 3 days before getting into the western Caribbean.
The only other models forecasting a low to form are the European and the NOGAPS. These two models move a weak low slowly up through the western Caribbean in 5-7 days. I am inclined to agree with this solution rather than the quick GFS. 5-7 days out the sub-tropical jet will start to lift north and relax the shear over the Caribbean, and the MJO upward-motion pulse will be in full swing. Also around that time the tropical wave along 59W right now will be moving into the western Caribbean, and may want to have its say in things, at least adding its heat to the area. Another reason I am skeptical of the GFS is that it hasn't had a good handle on this situation for a couple of days now. It has a problem handling the trough-split that will be helping to de-rail the sub-tropical jet, and it also has feedback issues, which makes it split the energy all over the place. This is the subject of today's Graphic of the Day:
Graphic of the Day:
Graphic of the Day: 06z GFS 144-hour 850mb Vorticity, showing how the GFS splits the Caribbean low into 4 different lows, spreading out the energy over a wide area. Interestingly, the GFS seems to spawn the two lows north of Hispaniola from a tropical wave that is currently in the central Atlantic near 59W, approaching the Antilles Islands. The GFS also forms these two lows right under 40 knots of shear associated with the sub-tropical jetstream, further reinforcing my point, that the GFS has serious issues.
So the bottom line here is that the western Caribbean will be becoming more favorable for tropical development in the 5-15 day period, and we may have a trigger already in place to start the process once the environment becomes favorable enough. Right now it's best to just watch and see how things evolve over the next couple of days. Regardless of any development of the system near Panama, it will be spreading heavy rains over Central America, and Florida should keep an eye out for tropical moisture moving north and dumping more rain on them in 6-10 days.
We shall see what happens!
NASA High-Resolution Visible Loop of the low near Panama
West Atlantic Visible Satellite: (click image for loop)
unique people have been here =)
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.