Tuesday, August 02, 2005

Tropical Depression Eight Update 022100Z At  5 PM EDT, the center of Tropical Depression Eight was at 28.5 North 66.7 West, 350 miles southwest of Bermuda and moving to the north at 13mph.  Maximum sustained winds are 35 mph and minimum central pressure is 1009 millibars (29.80").  The depression is forecast to become a tropical storm tonight Tropical Depression Eight Advisory Number One The system is marginally tropical (in terms of characteristics of a subtropical storm vice tropical).  Model guidanc is not exactly helpful as NOGAPS and UKMET did not place the storm correctly at the beginning of their forecasts (and the GFS also had issues that limit its usefulness).  Upper air enviroment isn't exactly favorable for much development, however, a small window of opportunity does exist for strengthening.  If a tropical storm does form, it will be the earliest eighth storm on record. Tropical Depression Eight Discussion Number One Forecast track Very cool that Dr Hart's cyclone phase page (Florida State meteorology professor) got mentioned in the discussion. Not much to comment on.  Steering enviroment is well defined, so it is pretty clear that the system will move north for a short period of time and then make a rather sharp turn to the right.  While the upper air enviroment is obviously more favorable than earlier, it still doesn't appear to offer much opportunity for intensification of the storm beyond minimal to moderate tropical storm status 2005 Hurricane Season, Weather comment []5:04:21 PM   trackback []

Tropical Depression Eight forms The 18Z limited area model forcasts were  just released with the title of Tropical Depression Eight.  Expect to see advisory package at 5 PM EDT.  Only land threat is to Bermuda and even then, not much greater than a minimal tropical storm. 2005 Hurricane Season, Weather comment []2:52:36 PM   trackback []

Tropics Watch 0802 Well, it is happening a bit later than originially anticipated, but the tropical wave that passed over the northern Carribean islands at the end of last week is starting to look like something: A BROAD AREA OF LOW PRESSURE IS CENTERED ABOUT 475 MILES SOUTHWEST OF BERMUDA...WITH A LARGE AREA OF SHOWERS AND THUNDERSTORMS LOCATED TO THE NORTH AND EAST OF AN ILL-DEFINED SURFACE CENTER. UPPER- LEVEL WINDS HAVE BECOME MORE FAVORABLE FOR DEVELOPMENT SINCE YESTERDAY...AND THIS SYSTEM HAS THE POTENTIAL TO DEVELOP INTO A TROPICAL DEPRESSION OR TROPICAL STORM DURING THE NEXT 24 HOURS AS IT MOVES SLOWLY NORTH-NORTHEASTWARD. INTERESTS IN BERMUDA SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. Passing over Hispanola did not help it, nor did the murderous amount of shear that existed immediately north of the island.  However, having survived that, it appears to have a reasonably bright future in the near term.  It's in a low-shear eviroment and while Sea Surface Temperatures aren't the warmest out there, they are warm enough to support development.  The Canadian and GFS models  (also the UKMET as well, though it wavered at one point) had been calling for this to happen and it looks to be playing out as they forecast.  A recon plane is scheduled to investigate the area tomorrow provided that the developing trend continues. Looking out to the east, the models are showing favor to a tropical wave that passed over the Cape Verde islands a couple of days ago.  This is how the Tropical Weather Discussion describes it: FAR E ATLC TROPICAL WAVE IS ALONG 26W S OF 17N MOVING W 10-15 KT. WEAK...BROAD MID LEVEL CURVATURE IS CENTERED ALONG THE WAVE WITH SAHARAN DUST MOSTLY TO THE W OF THE WAVE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 45 NM OF LINE 12N24W-11N28W. UKMET model has liked this one from the start. The GFS and Canadian models are also showing support for this to grow into something.  However, SSTs don't get favorable until 40° - 50° West.  (the wave will find warmer water sooner if it tracks due west, if it meanders north, it has a longer wait).  Because of that, not much would be expected from it during the next two or three days. After that however, it could get interesting.  The wildcard is how  the wave interacts with the dry Saharan Air Layer.   That could inhibit the wave's development. 2005 Hurricane Season, Weather comment []1:49:11 PM   trackback []