Tag: guidance

Hurricane Tomas in the early morning hours was found to have winds of 100MPH and Tomas is now a category 2 hurricane. With data from the reconnaissance plane and satellite imagery, Tomas is better organized but it was noted that the vertical stack of the storm is tilted northeastward with height. The tilting is probably due to the Southwesterly shear that is beginning to impact Hurricane Tomas. The shear has been forecast and further intensification will stop for about 48- 72 hours. There is the possibility Tomas may lose some strength during that forecast period. After that period, the shear will relax and further strengthening is forecast. Intensity guidance in at least the LGEM model does have Tomas strengthening and possibly be a major hurricane of at least a category 3 storm.

Hurricane Tomas is currently located south of a mid-level trough that is over the southwestern Atlantic. As this trough continues to move eastward a mid level ridge will build just north of Tomas and this will turn Tomas on a westward track for the next 2 or 3 days. Later in the forecast period, that ridge breaks down as a very large deep layer trough moves into the eastern U.S. and also digs southward. This will slow the forward speed of Tomas and also allow Tomas to gain latitude. Model guidance at days 4 and 5 is poor as far as the timing and the the sharpness of the turn to the north but there is a consensus that there will be the northern turn as Tomas will be forced north by the trough.

Invest 98L has been upgraded to Tropical Storm Paula as of the 5PM advisory from the NHC. Recon earlier today found winds of 60 MPH, but that might be a little conservative. The forecast is for Tropical Storm Paula for additional strengthening and Paula is forecast to possibly become a hurricane within 24 hours according to the models SHIPS, and LGEM. Strengthening will only be possible for a few days, then slow weakening on days 4 or 5. For the next few days the track for Paula will be NW then N. The western edge of a ridge that extends across northern Caribbean is expected to weaken because of a deep-layered trough that will be moving eastward across the Southeastern US. After that forecast period most of the guidance is suggesting that the trough will move east and then leave Paula in an area of weak steering currents and Paula is expected to drift eastward for for a day or two then possibly drift southward. Model guidance after day 3 or 4 and confidence is quite low. Whether Paula will stay in the Western Caribbean and impact Nicaragua or head north and northeast unfortunately it is too difficult to forecast.