TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 PM EDT TUE OCT 25 2011 

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF 
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE 
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE 
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL 
ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2345 UTC.

...SPECIAL FEATURE...

THE CENTER OF HURRICANE RINA AT 26/0000 UTC IS NEAR 17.5N 84.5W 
ABOUT 260 MI...425 KM ESE OF CHETUMAL AND 250 MI...405 KM SE OF 
COZUMEL MEXICO. RINA IS MOVING TOWARD THE WEST OR 270 DEGREES AT 
3 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 966 MB. THE 
MAXIMUM SUSTAINED WIND SPEEDS ARE 95 KT WITH GUSTS TO 115 KT. 
PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCPAT3/WTNT33 KNHC AND THE FULL 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC 
FOR MORE DETAILS. SCATTERED HEAVY SHOWERS AND THUNDERSTORMS ARE 
FROM 16N-21N BETWEEN 80W-87W. THE ENVIRONMENT APPEARS FAVORABLE 
FOR SOME ADDITIONAL INTENSIFICATION DURING THE NEXT DAY OR TWO 
AS THE CYCLONE MOVES OVER VERY WARM WATERS IN A REGION OF LOW 
WIND SHEAR.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH ENTERS THE ERN TROPICAL ATLC ACROSS THE SRN 
COAST OF SIERRA LEONE ALONG 7N12W TO 4N15W TO 3N22W. 
SCATTERED SHOWERS ARE WITHIN 120 NM ON EITHER SIDE OF THE TROUGH 
AXIS. A NEARLY STATIONARY 1008 MB LOW IS AROUND 12N45W WITH 
CLUSTERS OF SCATTERED MODERATE CONVECTION FROM 8N-13N BETWEEN 
40W-47W.

...DISCUSSION...

THE GULF OF MEXICO...
THE OUTER BANDS OF CONVECTION FROM RINA ARE ENTERING THE FAR SE 
GULF ACROSS THE YUCATAN CHANNEL. SEE SPECIAL FEATURES ABOVE FOR 
MORE DETAILS. OTHERWISE...WATER VAPOR IMAGERY DISPLAYS VERY DRY 
AIR AND STRONG SUBSIDENCE IN THE MID AND UPPER LEVELS OF THE 
ATMOSPHERE ACROSS THE GULF THIS EVENING. THIS UPPER AIRMASS IS 
SUPPRESSING ANY DEEP CONVECTION EVERYWHERE AT LOW LEVELS. MARINE 
OBSERVATIONS SHOW A VERY LOOSE PRESSURE GRADIENT WITH A LIGHT 
ANTICYCLONIC FLOW OVER THE AREA. LAST VISIBLE PICTURES OF THE 
DAY REVEALED CLUSTERS OF STRATOCUMULUS CLOUDS SCATTERED ACROSS 
THE BASIN. EXPECT MORE CONVECTION IN THE SE GULF DURING THE NEXT 
24-48 HOURS AS RINA APPROACHES THE NE YUCATAN PENINSULA. 

THE CARIBBEAN SEA...
HURRICANE RINA IS THE MAIN FOCUS PRODUCING SIGNIFICANT WEATHER 
ACROSS THE NW WATERS OF THE BASIN. SEE SPECIAL FEATURE 
DISCUSSION ABOVE FOR MORE DETAILS. A BROAD AREA OF LOW LEVEL 
MOISTURE MOVES ACROSS THE ERN AND CENTRAL CARIBBEAN NOTICED ON 
TPW PRODUCT. WITHIN THIS AREA OF DEEP MOISTURE...A 1009 MB LOW 
IS ANALYZED NEAR 15N70W. THE COMBINATION OF LOW LEVEL 
CONVERGENCE AROUND THE SURFACE LOW AND PLENTY OF MOISTURE 
AVAILABLE IS GENERATING A BROAD AREA OF SCATTERED HEAVY SHOWERS 
AND THUNDERSTORMS S OF 17N BETWEEN 65-77W. THIS AREA OF 
CONVECTION WILL CONTINUE TO MOVE WESTWARD OVER THE NEXT 24 HRS.

THE ATLANTIC OCEAN...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL TROUGH MOVING ACROSS 
THE WRN NORTH ATLC WATERS SUPPORTING A COLD FRONT EXTENDING INTO 
THE AREA ALONG 32N60W TO 27N64W TO 25N70W. THE STRONGEST 
CONVECTION IS N OF THE DISCUSSION AREA WHERE THE GREATEST 
DIFFLUENCE ALOFT IS NOTICED. ONLY SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS ARE WITHIN 20 NM ON EITHER SIDE OF THE FRONT AXIS 
S OF 32N. AN UPPER LEVEL LOW IS IN THE CENTRAL TROPICAL ATLC 
NEAR 18N41W. A SURFACE 1010 MB REFLECTION IS WELL TO THE E OF 
THE UPPER LOW NEAR 17N30W. THESE TWO FEATURES ARE PRODUCING AN 
AREA OF SCATTERED SHOWERS AND THUNDERSTORMS FROM 16N-20N BETWEEN 
27W-38W. OTHERWISE...A BROAD UPPER RIDGE COVERS THE CENTRAL AND 
ERN ATLC ANCHORED BY A WEAK 1018 MB HIGH CENTERED NEAR 29N35W 
PRODUCING FAIR WEATHER ACROSS THE REMAINDER OF THE DISCUSSION 
AREA.