Masters student in tropical meteorology at FSU. Raised in Alaskan blizzards, but drawn toward tropical cyclones by their superior PGF.
By: Levi32 , 6:41 PM GMT on June 05, 2009
Tropical Tidbit from 2:30pm eastern Time 6-5-09:
The GFS is continuing to develop a tropical cyclone in the western Caribbean early next week from an area of disturbed weather south of Panama and Costa Rica. A tropical wave in the eastern Pacific is helping to enhance thunderstorms in this area, as well as a strong monsoonal flow from the SW. An area of low pressure is forecasted to form in this region, and should drift very slowly towards the NNW over or near Nicaragua during the next few days.
The GFS seems to be rushing things a bit with cyclogenesis in the Caribbean, giving little time for the subtropical jetstream to lift far enough north to give some breathing room to the disturbance. Development seems more likely in 6-8 days, when environment becomes more favorable. I also feel that the model is mishandling the trough split getting ready to occur with the upper shortwave moving into the eastern Gulf of Mexico right now. We may get a sort of "double-split" with one piece of the trough digging southward towards the NW Caribbean and the other piece swinging out across Florida and planting itself south of the Carolinas. It will be interesting to see how the first piece interacts with the area of disturbed weather in the Caribbean. It is worth noting that all other models have dropped the low in recent runs, although most of them lower pressures in the area. It is possible that the GFS is getting plagued by its feedback and QPF issues, but it is hard to say.
We can't speculate on what might happen with this potential storm, but we can say with fair certainty that the environment is going to become more favorable for tropical cyclone formation in the Caribbean during the next 6-10 days. The models are forecasting the upper high in the east Pacific to nudge north into the southern Gulf of Mexico. Coupled with the trough split to the east, this should effectively split the subtropical jet and lift it to the north, allowing an area of lower wind shear to envelop the western Caribbean. Today's graphic of the day illustrates this with the 12z GFS shear forecast from this morning:
Graphic of the Day:
The MJO upward pulse is on the way as well, and should be in the western Caribbean in a few days. These factors will all make the environment more favorable in the western Caribbean, and that area will be monitored for development during the next 10 days. Regardless of development, please remember that this whole mess could be another big rain-maker for Florida if it migrates north in 6-10 days, so be aware. Countries in Central America may also get a lot of rain over the next few days.
We shall see what happens!
NW Atlantic Water-vapor Loop (to watch trough-split over north gulf coast)
West Atlantic Visible Satellite: (click image for loop)
unique people have been here =)
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