Posted by: JeffMasters, 1:38 PM GMT on October 19, 2010

Heavy thunderstorm activity has increased and grown more organized this morning over the southwestern Caribbean between Honduras and the Cayman Islands, in association with a tropical disturbance (Invest 99L). The storm is bringing heavy rain to the Cayman Islands; two inches has fallen so far this morning at Savannah on Grand Cayman Island. Recent satellite imagery shows that 99L has some rotation, and the winds on the northeast coast of Honduras at Puerto Lempira have shifted to the west-northwest, implying that 99L may be developing a surface circulation. Wind shear is a moderate 10 - 20 knots, which is low enough to allow some slow development. Water vapor satellite loops reveal that the atmosphere in the Western Caribbean is moist enough to support development, and the waters beneath are plenty warm, at 29°C. The latest SHIPS model forecast predicts that wind shear over the Western Caribbean will mostly remain in the moderate range, 10 - 20 knots, for the remainder of the week. The current north-northwest motion of 99L should continue until Wednesday, when a strong ridge of high pressure is forecast to build in, forcing 99L to the south or west. However, steering currents will be weak Wednesday through Friday, making it difficult to predict where 99L may wander to. The only models that develop 99L are the GFDL and HWRF. The GFDL model predicts that 99L will spend enough time over water to develop into a hurricane, and brings the storm to the coast of Mexico's Yucatan Peninsula on Sunday morning. The HWRF model has 99L making landfall over Honduras late this week, before the storm has a chance to develop into a hurricane. NHC is giving 99L a 40% chance of developing into a tropical depression by Thursday. I believe the odds are higher, near 60%. The Hurricane Hunters are on call to investigate 99L this afternoon.


Figure 1. Morning satellite image of Invest 99L.

Nice models! Looks set to hit either Nicaragua, Cuba, or, er, Spain?

yeah, really pinning it down aren't they!!!!

You could say that there is weather afoot.

We need rain. There is dust and the plants look parched, plus I'm still looking at my empty cistern that I cleaned out last time we thought bad weather was coming.

A little rain would be nice. Preferably without the big winds.

Amen to that. It's like driving around in the desert out there. I'm buying facemasks tomorrow if we don't get some rain.

Let's hope for RAIN - PLEASE --- we'll take a tiny little wind if we have to. And as we are putting in our wish list - NO big waves. Had them already this year.

Anyone have any insight to the weather for this weekend. I saw this today.

http://www.nhc.noaa.gov/


DC

waiting to see what happens.... will know more as the hours progress into days.