764
WTNT43 KNHC 051449
TCDAT3
TROPICAL STORM RAFAEL DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL AL182024
1000 AM EST TUE NOV 05 2024
SATELLITE IMAGERY SHOWS THAT THE CONVECTION HAS INCREASED NEAR THE
CENTER OF RAFAEL DURING THE PAST SEVERAL HOURS. HOWEVER, REPORTS
FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT SUGGEST THAT
THIS HAS NOT YET TRANSLATED INTO STRENGTHENING, POSSIBLY DUE TO
WHAT LOOKS LIKE A TONGUE OF DRY AIR SEEN ENTRAINING INTO THE
CENTER IN MICROWAVE IMAGERY. THE AIRCRAFT REPORTED MAXIMUM WINDS
OF 54 KT AT 850 MB WITH A MINIMUM CENTRAL PRESSURE NEAR 994 MB.
BASED ON THE AIRCRAFT DATA, THE INITIAL INTENSITY REMAINS 50 KT.
ONE NOTE IS THE RADIUS OF MAXIMUM WINDS HAS DECREASED TO ABOUT 20
N MI, SUGGESTING THAT RAFAEL IS TRYING TO DEVELOP A BETTER-DEFINED
INNER CORE DESPITE THE APPARENT DRY AIR.
THE INITIAL MOTION IS STILL NORTHWESTWARD AT 320/11 KT. RAFAEL IS
CURRENTLY ON THE SOUTHWESTERN SIDE OF A LOW- TO MID-LEVEL RIDGE OVER
THE WESTERN ATLANTIC, AND THIS FEATURE SHOULD STEER THE CYCLONE
GENERALLY NORTHWESTWARD FOR THE NEXT COUPLE OF DAYS, WITH THE CENTER
PASSING NEAR THE CAYMAN ISLANDS AND OVER WESTERN CUBA. AFTER THAT
TIME, THERE IS A SIGNIFICANT SPREAD IN THE TRACK GUIDANCE. WHILE ALL
OF THE GUIDANCE SUGGESTS THAT RAFAEL SHOULD SHEAR APART OVER THE
CENTRAL AND NORTHERN GULF, THE GFS TAKES LONGER TO SHOW THIS
HAPPENING THAN THE ECMWF/UKMET. IN ADDITION, THE GFS SHOWS A WEAKER
RIDGE NORTH OF THE SYSTEM, WHILE THE ECMWF/UKMET SHOW A STRONGER
RIDGE. THE RESULT IS THAT THE GFS SHOWS A NORTHWARD MOTION WITH
LANDFALL ON THE NORTHERN GULF COAST, WHILE THE ECMWF/UKMET SHOW A
WESTERLY MOTION ACROSS THE CENTRAL GULF OF MEXICO. UNTIL THERE IS A
CLEARER SIGNAL ON WHICH OF THESE SCENARIOS IS MORE LIKELY, THE
FORECAST COMPROMISES BETWEEN THESE EXTREMES WITH A SLOW MOTION OVER
THE NORTHERN GULF OF MEXICO.
CONDITIONS ARE FAVORABLE FOR STEADY TO RAPID STRENGTHENING DURING
THE NEXT 24-36 H IF RAFAEL CAN DEVELOP A STRONGER INNER WIND CORE.
BASED ON THE EXPECTATION THAT THE CORE WILL FORM, THE SYSTEM IS
FORECAST TO REACH HURRICANE STRENGTH IN ABOUT 12 H AND CONTINUE TO
STRENGTHEN UNTIL IT REACHES CUBA. ONCE THE CENTER IS NORTH OF 25N
IN THE GULF OF MEXICO, IT IS LIKELY TO ENCOUNTER INCREASING
VERTICAL WIND SHEAR, DRY AIR ENTRAINMENT, AND COOLER SEA SURFACE
TEMPERATURES, WHICH SHOULD LEAD TO RAFAEL WEAKENING AND EVENTUALLY
SHEARING APART VERTICALLY. THE NEW INTENSITY FORECAST REMAINS ON
THE HIGH SIDE OF THE INTENSITY GUIDANCE AND IS SIMILAR TO THE
PREVIOUS FORECAST.
KEY MESSAGES:
1. RAFAEL IS FORECAST TO BE NEAR HURRICANE INTENSITY WHEN IT PASSES
NEAR OR OVER THE CAYMAN ISLANDS BY TONIGHT WHERE DAMAGING
HURRICANE-FORCE WINDS, A DANGEROUS STORM SURGE, AND DESTRUCTIVE
WAVES ARE EXPECTED. RAFAEL SHOULD REACH WESTERN CUBA AND THE ISLE OF
YOUTH ON WEDNESDAY. A HURRICANE WARNING IS IN EFFECT FOR THIS
REGION, WHERE A LIFE-THREATENING STORM SURGE AND DESTRUCTIVE WAVES
ARE ALSO EXPECTED.
2. TROPICAL STORM CONDITIONS ARE EXPECTED IN JAMAICA THROUGH THIS
AFTERNOON. TROPICAL STORM CONDITIONS ARE EXPECTED IN THE LOWER
AND MIDDLE FLORIDA KEYS BEGINNING WEDNESDAY AND WEDNESDAY NIGHT.
3. IT IS TOO SOON TO DETERMINE WHAT, IF ANY, IMPACTS RAFAEL COULD
BRING TO PORTIONS OF THE NORTHERN GULF COAST. RESIDENTS IN THIS
AREA SHOULD REGULARLY MONITOR UPDATES TO THE FORECAST.
4. RAFAEL WILL BRING AREAS OF HEAVY RAIN ACROSS PORTIONS OF THE
WESTERN CARIBBEAN THROUGH EARLY THURSDAY, INCLUDING THE ISLANDS OF
JAMAICA AND THE CAYMAN, ALONG WITH SOUTHERN AND WESTERN PORTIONS OF
CUBA. FLASH FLOODING AND MUDSLIDES ARE POSSIBLE ALONG THE HIGHER
TERRAIN IN JAMAICA AND CUBA.
FORECAST POSITIONS AND MAX WINDS
INIT 05/1500Z 17.8N 78.6W 50 KT 60 MPH
12H 06/0000Z 19.4N 79.9W 65 KT 75 MPH
24H 06/1200Z 21.3N 81.5W 75 KT 85 MPH
36H 07/0000Z 23.2N 83.1W 80 KT 90 MPH
48H 07/1200Z 24.4N 84.3W 80 KT 90 MPH
60H 08/0000Z 25.1N 85.7W 80 KT 90 MPH
72H 08/1200Z 25.6N 87.1W 75 KT 85 MPH
96H 09/1200Z 26.8N 89.3W 60 KT 70 MPH
120H 10/1200Z 28.0N 90.5W 45 KT 50 MPH
FORECASTER BEVEN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page