Tropical Weather


Invest 91L located about 350 miles East – Southeast of the southern Windward Islands has been slowly getting better organized and is forecast to become a Tropical Depression or Tropical Storm in the next day or two. The overall environment and conditions are conducive for continuing development as the system heads W-WNW. A reconnaissance flight is scheduled later today (2pm). Most models are forecasting that Invest 91L will eventually turn N or NNE but the timing between the models makes things a little unclear. The latest models have it tracking between eastern Cuba and Hispaniola as a frontal system picks it up in a few days. Until we have the data from recon I would not begin to estimate what intensity will be.

Visible Satellite image of Invest 91L
AVN Satellite image of Invest 91L
Models for Invest 91L
Tropical Weather

Invest 99L – A Possible Florida Threat??

Invest 99L which has been lingering around the Southwestern Caribbean is finally beginning to move away from the coasts of Nicaragua & Honduras. With landfall interaction, it was impossible for 99L to even try to develop. Now that it has been been heading N or NNW it has a much better chance of developing. This is the time of the year where the models have problems and this may be the case with 99L. Many of the models at this time are not seeing any type development but the GFDL and HWRF does favor development. Whether 99L will be a Florida threat or not is a forecast that is so very difficult to answer, at least for the next few days. Hopefully, with a few hours or so we may have a better idea of what might happen as the reconnaissance flight is on it’s way. Just looking at the satellite presentation, it does look like there is circulation at the mid and upper levels but not yet at the surface. I am sure this is what recon will find.

Visible Satellite image of Invest 99L
AVN Satellite image of Invest 99L
Water Vapor Satellite image of US and Invest 99L
Shear Map
Steering Layer Map
Euro Model for Invest 99L at 216 hours
GFS Model for Invest 99L at 132 hours

Below are the two models GFDL & HWRF which develop 99L into a hurricane. Only if shear abates, the high pressure system that will build after the trough has gone through and the high heads east and 99L lingers into the Southern Gulf of Mexico, then the chances for 99L to head to Florida as a tropical cyclone may increase but I doubt this will happen as there a just too many variables that have to work in unison.

GFDL Model at 144 hours
HWRF Model at 216 hours