000
AXNT20 KNHC 021153
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE OCT 02 2012

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
VALID THROUGH 1015 UTC.

...SPECIAL FEATURE...

THE CENTER OF TROPICAL STORM NADINE AT 02/1200 UTC IS NEAR 34.3N 
37.8W. NADINE IS ABOUT 578 NM TO THE WEST-SOUTHWEST OF THE 
AZORES. NADINE IS MOVING EAST-SOUTHEASTWARD 6 KNOTS. THE 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 995 MB. THE MAXIMUM 
SUSTAINED WIND SPEEDS ARE 55 KNOTS WITH GUSTS TO 65 KNOTS. 
TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 100 NM FROM THE 
CENTER. TROPICAL STORM CONDITIONS ARE EXPECTED IN THE AZORES BY 
WEDNESDAY NIGHT. NADINE IS EXPECTED TO PRODUCE TOTAL RAINFALL 
ACCUMULATIONS OF 1 TO 2 INCHES IN PARTS OF THE AZORES THROUGH 
THURSDAY. PLEASE READ THE FORECAST/ADVISORY UNDER AWIPS/WMO 
HEADERS MIATCMAT4/WTNT24 KNHC...AND THE PUBLIC ADVISORY... 
MIATCPAT4/WTNT34 KNHC...FOR MORE DETAILS. CONVECTIVE 
PRECIPITATION...SCATTERED MODERATE TO STRONG FROM 33N TO 35N 
BETWEEN 37W AND 39W.

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 37W TO THE SOUTH OF 
20N. A 1009 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 10N.
THE WAVE HAS BEEN MOVING WESTWARD 10 TO 15 KNOTS DURING THE LAST 
24 HOURS. CONVECTIVE PRECIPITATION...SCATTERED STRONG WITHIN
90 NM ON EITHER SIDE OF 19N32W 18N34W 15N36W 13N39W AND FROM
10N TO 13N BETWEEN 37W AND 42W. ENVIRONMENTAL CONDITIONS ARE 
EXPECTED TO BE CONDUCIVE FOR THE DEVELOPMENT OF THIS SYSTEM.
THE CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT
48 HOURS IS HIGH.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 50W/51W TO THE SOUTH OF 
20N...MOVING WESTWARD 10 TO 15 KNOTS DURING THE LAST 24 HOURS.
CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG 
FROM 10N TO 22N BETWEEN 47W AND 52W.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA-BISSAU NEAR 
12N16W 11N19W 12N27W 10N37W 5N48W. THE ITCZ DOES NOT EXIST
AT THIS MOMENT DUE TO THE LARGE-SCALE NORTHERLY WIND FIELD.
CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO STRONG FROM
3N TO 10N TO THE EAST OF 18W.

...DISCUSSION...

THE GULF OF MEXICO...

THE DEEP LAYER TROUGH THAT WAS MOVING THROUGH THE CENTRAL U.S.A. 
24 HOURS AGO HAS SLOWED DOWN AND STALLED. IT PASSES THROUGH 
MISSOURI AND ARKANSAS...THROUGH THE LOWER RIO GRANDE VALLEY OF 
TEXAS TO THE MEXICO COAST ALONG 20N. THIS TROUGH SUPPORTS A COLD 
FRONT THAT PASSES THROUGH THE FLORIDA PANHANDLE ALONG 86W...
TO THE NORTHERN YUCATAN PENINSULA OF MEXICO...ACROSS THE ISTHMUS 
OF TEHUANTEPEC OF MEXICO TO 20N99W. BROKEN STRATIFORM CLOUDS ARE 
TO THE NORTH OF 25N TO THE EAST OF 96W. BROKEN TO OVERCAST 
MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION ARE TO THE EAST 
OF 20N96W 30N86W. 

SURFACE HIGH PRESSURE MOVES INTO THE GULF OF MEXICO AS A RIDGE 
PASSES THROUGH SOUTH TEXAS TO THE ISTHMUS OF TEHUANTEPEC
OF MEXICO. 

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE 
OFFSHORE FORECAST...MIAOFFNT4...FOR DETAILS ABOUT THE
20 TO 25 KNOT WINDS AND 8 TO 9 FOOT SEA HEIGHTS WITH
THE COLD FRONT.

THE CARIBBEAN SEA...

A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS 
NEAR 19N87W...MOVING CLOSER TO EAST CENTRAL COAST OF THE
YUCATAN PENINSULA OF MEXICO. CYCLONIC WIND FLOW THAT IS 
MOVING AROUND THIS CENTER COVERS THE CARIBBEAN SEA AND CENTRAL 
AMERICA FROM NICARAGUA TO THE YUCATAN PENINSULA BETWEEN 80W AND 
91W. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO 
ISOLATED STRONG FROM THE ISTHMUS OF TEHUANTEPEC OF MEXICO INTO 
GUATEMALA BELIZE AND HONDURAS...LINGERING RAINSHOWERS IN THE 
CARIBBEAN SEA TO THE NORTH OF 15N TO THE WEST OF 80W.
THE 24 HOUR RAINFALL TOTAL FOR THE PERIOD THAT ENDED
AT 02/0000 UTC FOR TEGUCIGALPA HONDURAS WAS 1.39 INCHES.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 30N43W IN 
THE ATLANTIC OCEAN...TO A 24N51W CYCLONIC CIRCULATION 
CENTER...TO 18N57W AND 12N61W. MIDDLE LEVEL TO UPPER LEVEL 
NORTHERLY WIND FLOW COVERS THE CARIBBEAN SEA TO THE EAST OF THE 
WINDWARD PASSAGE. THE NORTHERLY WIND FLOW IS A COMBINATION OF 
THE NORTHERLY WIND FLOW FROM THE ATLANTIC OCEAN TROUGH...AND THE 
WIND FLOW THAT IS ON THE EASTERN SIDE OF AN UPPER LEVEL RIDGE. 
THE UPPER LEVEL RIDGE EXTENDS FROM 15N80W IN THE WESTERN 
CARIBBEAN SEA...ACROSS CUBA AND THE BAHAMAS...BEYOND 32N75W
IN THE ATLANTIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED 
STRONG FROM 8N TO 10.5N BETWEEN 58W AND 61W ALONG THE COASTS OF 
GUYANA VENEZUELA AND TRINIDAD...SCATTERED MODERATE TO ISOLATED 
STRONG TO THE NORTHEAST OF THE LINE THAT RUNS FROM 18N71W TO 
11N64W. THE 24 HOUR RAINFALL TOTAL FOR THE PERIOD THAT ENDED AT 
02/0000 UTC FOR GUADELOUPE WAS 0.85 OF AN INCH.

NUMEROUS STRONG CONVECTIVE PRECIPITATION IS OCCURRING FROM 19N 
TO 21N BETWEEN 82W AND 85W TO THE SOUTH OF WESTERN CUBA. THE 
REST OF THE STRONG CONVECTIVE PRECIPITATION FROM SIX HOURS AGO 
HAS WEAKENED AND DISSIPATED FOR THE MOMENT. STRONG PRECIPITATION
HAS BEEN OCCURRING IN AN AREA OF BROAD SURFACE LOW PRESSURE AND 
UPPER LEVEL DIFFLUENT WIND FLOW.

THE MONSOON TROUGH IS ALONG 9N/10N BETWEEN 73W IN COLOMBIA AND 
80W...AND THEN CUTTING ACROSS SOUTHEASTERN NICARAGUA BEYOND 
NORTHWESTERN NICARAGUA. CONVECTIVE PRECIPITATION...SCATTERED
STRONG IN COLOMBIA AND VENEZUELA FROM 7N TO 9N BETWEEN 72W AND 
75W...WIDELY SCATTERED MODERATE TO ISOLATED STRONG IN THE 
SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO THE SOUTH OF 14N
BETWEEN 78W AND 82W.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE 
OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT THE
20 TO 25 KNOT WINDS AND 9 FOOT SEA HEIGHTS FROM 11N TO 17N
BETWEEN 68W AND 79W.

THE ATLANTIC OCEAN...

SCATTERED MODERATE TO STRONG CONVECTIVE PRECIPITATION IS FROM 
CUBA BEYOND 32N BETWEEN 74W AND FLORIDA...INCLUDING IN PARTS
OF SOUTH FLORIDA. THIS IS PRECIPITATION THAT IS UNDER AN UPPER 
LEVEL RIDGE...IN AN AREA OF MOIST SURFACE SOUTHERLY WIND FLOW 
THAT ALSO IS WITHIN 500 NM TO THE EAST OF THE GULF OF MEXICO 
COLD FRONT.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 30N43W IN 
THE ATLANTIC OCEAN...TO A 24N51W CYCLONIC CIRCULATION 
CENTER...TO 18N57W AND 12N61W. CONVECTIVE PRECIPITATION... 
SCATTERED STRONG FROM 8N TO 10.5N BETWEEN 58W AND 61W ALONG THE 
COASTS OF GUYANA VENEZUELA AND TRINIDAD...SCATTERED MODERATE TO 
STRONG IN THE CARIBBEAN SEA FROM 16N TO 18N BETWEEN 61W AND 
65W...SCATTERED MODERATE IN THE ATLANTIC OCEAN FROM 23N TO 28N
BETWEEN 43W AND 53W.

BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN 
TO THE NORTH OF 20N BETWEEN AFRICA AND 80W.

PLEASE READ THE HIGH SEAS FORECASTS...MIAHSFAT2...FOR DETAILS 
ABOUT A 37W TROPICAL WAVE AND THEN A POSSIBLE TROPICAL CYCLONE 
1011 MB NEAR 14N39W AT 24 HOURS...AND 1006 MB NEAR 19N41W AT
48 HOURS. EXPECT ALSO 20 KNOT WINDS AND 9 FOOT SEA HEIGHTS
TO THE NORTH OF 29N TO THE EAST OF 40W AT 24 HOURS.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
MT