ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION FOUR DISCUSSION NUMBER 1 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042006 500 PM EDT MON AUG 21 2006 THE AREA OF LOW PRESSURE SOUTHEAST OF THE CAPE VERDE ISLANDS HAS BEEN MAINTAINING ENOUGH CONVECTIVE BANDING TODAY TO WARRANT DVORAK CLASSIFICATIONS OF T1.5 FROM TAFB AND SAB AT 18Z. SINCE THEN...A SMALL BURST OF CONVECTION HAS DEVELOPED NEAR THE CIRCULATION CENTER. GIVEN THIS...AND THE BROAD CYCLONIC ENVELOPE OF THE LOW...ADVISORIES ARE INITIATED ON TROPICAL DEPRESSION FOUR. THE INITIAL MOTION IS 285/10. THE DEPRESSION IS SOUTH OF THE SUBTROPICAL RIDGE...BUT THIS RIDGE IS FORECAST BY GLOBAL MODELS TO SLIDE EASTWARD AS A SERIES OF MID-LATITUDE SHORT WAVES MOVE THROUGH THE CENTRAL ATLANTIC AND ERODE THE RIDGE. THIS SHOULD ALLOW THE DEPRESSION TO TAKE A TRACK BETWEEN WEST-NORTHWEST AND NORTHWEST AROUND THE PERIPHERY OF THE RIDGE THROUGHOUT MUCH OF THE FORECAST PERIOD. THE OFFICIAL FORECAST IS IN GOOD AGREEMENT WITH THE GFS AND GFDL GUIDANCE...AS WELL AS THE BAM SUITE OF MODELS. NEITHER THE UKMET NOR NOGAPS HANG ON TO THE CYCLONE AND THESE MODELS TAKE ITS REMNANTS WESTWARD. OUTER BANDING STRUCTURES ARE WELL DEFINED...BUT OVERALL THE CONVECTIVE SIGNATURE IS STILL A LITTLE THIN. WATER TEMPERATURES SHOULD BE WARM ENOUGH FOR THE NEXT DAY OR SO TO SUPPORT DEVELOPMENT AND THE SHEAR IS LIGHT. DURING DAYS 2 AND 3 OF THE FORECAST PERIOD THE CYCLONE WILL BE MOVING OVER SOMEWHAT COOLER WATERS AND THE OFFICIAL FORECAST SHOWS ONLY SLOW DEVELOPMENT AFTER THAT. THE INTENSITY FORECAST IS CLOSE TO A BLEND OF THE SHIPS AND GFDL GUIDANCE. PORTIONS OF THE CAPE VERDE ISLANDS ARE WITHIN THE FORECAST TROPICAL STORM FORCE WIND SWATH...AND THE GOVERNMENT OF THE CAPE VERDE ISLANDS HAS ISSUED A TROPICAL STORM WARNING. FORECAST POSITIONS AND MAX WINDS INITIAL 21/2100Z 12.5N 21.5W 30 KT 12HR VT 22/0600Z 13.0N 23.0W 35 KT 24HR VT 22/1800Z 14.2N 25.2W 45 KT 36HR VT 23/0600Z 15.5N 27.5W 50 KT 48HR VT 23/1800Z 17.0N 30.0W 55 KT 72HR VT 24/1800Z 20.0N 35.5W 55 KT 96HR VT 25/1800Z 23.5N 41.0W 60 KT 120HR VT 26/1800Z 26.5N 46.5W 60 KT $$ FORECASTER FRANKLIN NNNN
Alternate Formats
About Alternates -
E-Mail Advisories -
RSS Feeds
Cyclone Forecasts
Latest Advisory -
Past Advisories -
About Advisories
Marine Forecasts
Latest Products -
About Marine Products
Tools & Data
Satellite Imagery -
US Weather Radar -
Aircraft Recon -
Local Data Archive -
Forecast Verification -
Deadliest/Costliest/Most Intense
Learn About Hurricanes
Storm Names
Wind Scale -
Prepare -
Climatology -
NHC Glossary -
NHC Acronyms -
Frequently Asked Questions -
AOML Hurricane-Research Division
About Us
About NHC -
Mission/Vision -
Other NCEP Centers -
NHC Staff -
Visitor Information -
NHC Library
NOAA/
National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
11691 SW 17th Street
Miami, Florida, 33165-2149 USA
nhcwebmaster@noaa.gov
Disclaimer
Privacy Policy
Credits
About Us
Glossary
Career Opportunities
Page last modified: Monday, 11-Sep-2006 11:28:35 UTC