ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM OLAF DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2 PM PDT FRI OCT 03 2003 IN SPITE OF DVORAK INTENSITY ESTIMATES OF 25 KT FROM AFWA AND 30 KT FROM TAFB AND SAB...A SHIP WITH A GOOD HISTORY REPORTED 45 KT WINDS CLOSE TO THE CENTER OF THE TROPICAL CYCLONE. SINCE THAT TIME THE DEEP CONVECTION HAS BEEN PULLED A LITTLE FARTHER AWAY FROM THE EXPOSED CENTER AND SO THE ADVISORY INTENSITY WINDS ARE ONLY RAISED TO 40 KT...STILL WELL ABOVE THE SATELLITE ESTIMATES. A QUIKSCAT PASS ALONG WITH MORE VISIBLE IMAGERY HAS NECESSITATED A RELOCATION OF THE CENTER TO THE NORTH OF THE PREVIOUS TRACK. THE INITIAL MOTION IS NOW ESTIMATED TO BE 310/6. SOME FAIRLY LARGE ADJUSTMENTS HAVE ALSO BEEN MADE TO THE FORECAST TRACK. THE GFS...GFDL...AND NOGAPS TAKE OLAF SLOWLY NORTHWARD TOWARD THE MEXICAN COAST OVER THE NEXT 24 HOURS...AND THEN BEND THE TRACK TO THE NORTHWEST AT VARIOUS RATES AS OLAF ENCOUNTERS A WEAK MID-LEVEL HIGH OVER MEXICO. THERE IS A LOT OF SOUTHWESTERLY LOW-LEVEL FLOW BEHIND TROPICAL STORM NORA THAT COULD PUSH OLAF NORTHWARD. ON THE OTHER HAND...WITH ALL THE DEEP CONVECTION TO THE SOUTH AND WEST OF THE CENTER DUE TO THE PREVAILING SHEAR...THE STORM-SCALE FORCING WOULD TEND TO DRAG THE CENTER MORE TO THE WEST. THE OFFICIAL FORECAST IS ADJUSTED TO THE RIGHT OF THE PREVIOUS ADVISORY...BUT NOT AS FAR AS THE GFS/GFDL/NOGAPS GUIDANCE. OLAF COULD MOVE CLOSER TO THE COAST THAN FORECAST...BUT MY FEELING IS THAT IT WOULD HAVE TO DO SO AS A WEAK AND SHEARED SYSTEM. BOTH THE SHIPS AND GFDL GUIDANCE TAKE OLAF TO HURRICANE STRENGTH WITHIN 36-48 HOURS. GIVEN THE SHEAR...I FIND THAT OUTCOME HARD TO ACCEPT. THE OFFICIAL FORECAST SHOWS STRENGTHENING...BUT ONLY AFTER 36 HOURS WHEN THE NORTHEASTERLY SHEAR IS FORECAST TO ABATE. FORECASTER FRANKLIN FORECAST POSITIONS AND MAX WINDS INITIAL 03/2100Z 12.7N 99.6W 40 KT 12HR VT 04/0600Z 13.2N 100.0W 40 KT 24HR VT 04/1800Z 14.0N 100.5W 40 KT 36HR VT 05/0600Z 14.7N 101.0W 40 KT 48HR VT 05/1800Z 15.3N 101.6W 45 KT 72HR VT 06/1800Z 15.9N 102.5W 50 KT 96HR VT 07/1800Z 16.5N 103.5W 55 KT 120HR VT 08/1800Z 17.0N 104.5W 60 KT 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, 07-Feb-2005 16:50:00 UTC