ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM RICK DISCUSSION NUMBER 19 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP202009 800 PM PDT MON OCT 19 2009 RICK HAS BEEN WEAKENING AT A RAPID PACE...ALMOST AS FAST AS IT STRENGTHENED SEVERAL DAYS AGO. CONVENTIONAL AND MICROWAVE SATELLITE DATA SHOW THAT THE LOW-LEVEL CENTER IS NOW COMPLETELY EXPOSED TO THE WEST AND SOUTHWEST OF A SHAPELESS CLUSTER OF DEEP CONVECTION. DVORAK FINAL-T AND CI NUMBERS ARE NOW 3.5/4.5 FROM TAFB AND SAB...BUT BOTH AGENCIES WERE CONSTRAINED BY THE DVORAK RULES AND ACTUALLY HAD DATA T-NUMBERS OF 3.0. IN ADDITION...THE LATEST UW-CIMMS ADT 3-HOUR ESTIMATE IS 3.1 WITH A CI OF 3.6. THEREFORE... RICK IS DOWNGRADED TO A 60-KT TROPICAL STORM. STRONG UPPER-LEVEL WESTERLY WINDS AND DRY...STABLE AIR TO THE WEST OF RICK ARE THE LIKELY CAUSES FOR THE RAPID WEAKENING OF RICK OVER THE PAST DAY OR SO. SINCE THE SHEAR IS NOT EXPECTED TO ABATE AND THE AMBIENT ENVIRONMENT IS FORECAST TO REMAIN STABLE...RICK SHOULD CONTINUE TO WEAKEN OVER THE NEXT COUPLE OF DAYS. THE NEW INTENSITY FORECAST IS SIGNIFICANTLY LOWER THAN THE PREVIOUS ONE DUE TO THE RECENT WEAKENING TREND...BUT IT IS STILL HIGHER THAN THAT SHOWN BY THE STATISTICAL SHIPS AND LGEM MODELS. ALL IN ALL...IT IS CLOSE TO THE INTENSITY CONSENSUS AND INDICATES A MORE GRADUAL WEAKENING THAN HAS OCCURRED OVER THE PAST DAY OR TWO. RICK IS STILL FORECAST TO BE A TROPICAL STORM AS IT MOVES NEAR SOUTHERN BAJA CALIFORNIA AND TOWARDS THE COAST OF MAINLAND MEXICO. RICK IS NOW MOVING NORTHWARD WITH AN INITIAL MOTION OF 350 DEGREES AT 7 KT. THE TRACK GUIDANCE IS STILL IN GOOD AGREEMENT IN SHOWING A NORTH-NORTHEASTWARD TO NORTHEASTWARD TURN OVER THE NEXT 24 TO 36 HOURS AS RICK GETS PICKED UP BY A SHORTWAVE TROUGH CURRENTLY ALONG THE WEST COAST OF THE UNITED STATES. THE GUIDANCE ENVELOPE AND THE MODEL CONSENSUS TVCN HAVE SHIFTED JUST A LITTLE TO THE EAST AND CONTINUE TO SHOW THE CENTER OF RICK PASSING JUST TO THE SOUTHEAST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. THE GOVERNMENT OF MEXICO HAS CHANGED THE HURRICANE WATCH FOR SOUTHERN BAJA CALIFORNIA TO A TROPICAL STORM WATCH DUE TO THE UPDATED INTENSITY FORECAST. FORECAST POSITIONS AND MAX WINDS INITIAL 20/0300Z 19.1N 111.8W 60 KT 12HR VT 20/1200Z 19.9N 111.6W 50 KT 24HR VT 21/0000Z 21.3N 110.5W 50 KT 36HR VT 21/1200Z 23.0N 108.8W 45 KT 48HR VT 22/0000Z 24.8N 106.8W 30 KT...INLAND 72HR VT 23/0000Z...DISSIPATED $$ FORECASTER BERG/BROWN 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: Thursday, 31-Dec-2009 12:09:31 UTC