[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271744
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SUN SEP 27 2015

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1730 UTC.

...SPECIAL FEATURES...

TROPICAL DEPRESSION IDA IS CENTERED NEAR 24.8N 48.4W AT 27/1500
UTC OR ABOUT 920 NM E-NE OF THE NORTHERN LEEWARD ISLANDS MOVING
W AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB.
MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT.
CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 22N-28N
BETWEEN 45W-54W. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY
UNDER AWIPS/WMO HEADERS MIATCMAT5/ WTNT25 KNHC FOR MORE DETAILS.

AN AREA OF INTEREST IS AT ABOUT 370 NM SSW OF BERMUDA WHERE
SHOWERS AND THUNDERSTORMS ARE SHOWING SOME SIGNS OF ORGANIZATION
IN ASSOCIATION WITH A 1010 MB SURFACE LOW CENTERED NEAR 27N69W.
SOME GRADUAL DEVELOPMENT IS POSSIBLE AS THE SYSTEM MOVES NW
BEFORE UPPER-LEVEL WINDS BECOME UNFAVORABLE FOR ADDITIONAL
DEVELOPMENT. THERE IS A MEDIUM CHANCE OF TROPICAL DEVELOPMENT
OVER THE NEXT 48 HOURS.

...TROPICAL WAVES...

A TROPICAL WAVE IS MOVING ACROSS THE CENTRAL ATLANTIC WITH AXIS
EXTENDING FROM 14N39W TO 05N39W...MOVING W NEAR 10 KT OVER THE
PAST 24 HOURS. SSMI TPW IMAGERY INDICATES THE WAVE IS EMBEDDED
WITH A SURGE OF DEEP MOISTURE SUPPORTING CLUSTERS OF SCATTERED
MODERATE CONVECTION OBSERVED FROM 04N-11N AND E OF 41W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL
ATLANTIC NEAR 14N17W TO 12N32W TO 08N38W. THE ITCZ BEGINS W OF
THE TROPICAL WAVE NEAR 06N42W AND CONTINUES INTO SOUTH AMERICA
NEAR 03N51W. ASIDE FROM THE CONVECTION RELATED TO THE TROPICAL
WAVE...CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 05N-
14N BETWEEN 21W-36W.

...DISCUSSION...

GULF OF MEXICO...

AN UPPER-LEVEL TROUGH EXTENDS FROM OVER THE CENTRAL CONUS
THROUGH A DEVELOPING CUTOFF UPPER-LEVEL LOW CENTERED OVER NE
MEXICO AND EXTENDING E ACROSS THE NW GULF. AT THE SURFACE...A
1007 MB LOW IS LOCATED NEAR 27N93W WITH SURFACE LOW EXTENDING
FROM 25N94W TO 29N94W. SCATTERED LIGHT TO MODERATE CONVECTION IS
IN THE VICINITY OF THIS LOW MAINLY N OF 26N AND W OF 89W. A
DIFFLUENT FLOW PREVAILS ACROSS THE EASTERN HALF OF THE BASIN
SUPPORTING CLUSTERS OF MODERATE CONVECTION ACROSS THE AREA W OF
87W. TO THE S...ANOTHER SURFACE LOW IS LOCATED OVER THE
NORTHERN COAST OF THE YUCATAN PENINSULA NEAR 21N88W EXTENDING A
SURFACE TROUGH TO 23N88W. SCATTEROMETER DATA DEPICTS A GENTLE TO
MODERATE EASTERLY FLOW ACROSS THE NORTHERN GULF N OF 26N WHILE A
LIGHT EASTERLY FLOW PREVAILS S OF 26N. LOOKING AHEAD...THE
LOW/SURFACE TROUGH IN THE NW GULF IS EXPECTED TO MOVE NW THROUGH
BEFORE DISSIPATING WHILE THE LOW OVER THE YUCATAN IS EXPECTED TO
MOVE N INTO THE CENTRAL GULF TODAY THEN N-NE THROUGH EARLY NEXT
WEEK.

CARIBBEAN SEA...

AN UPPER-LEVEL RIDGE COVERS THE CARIBBEAN MAINLY W OF 70W WHILE
AN UPPER-LEVEL LOW CENTERED E OF THE LEEWARD ISLANDS EXTENDS W
ACROSS THE CARIBBEAN WATERS E OF 70W. A DIFFLUENT FLOW PREVAILS
ACROSS THE W CARIBBEAN SUPPORTING CLUSTERS OF MODERATE
CONVECTION W OF 80W. FAIR WEATHER PREVAILS ACROSS THE REMAINDER
OF THE BASIN. SCATTEROMETER DATA DEPICTS GENTLE TO MODERATE
TRADES ACROSS MOST OF THE CARIBBEAN WITH FRESH TO STRONG WINDS
PULSING EACH NIGHT OFF COLOMBIA AND W VENEZUELA. LITTLE CHANGE
IS EXPECTED OVER THE NEXT 24 HOURS.

...HISPANIOLA...

SKIES ARE CLEAR ACROSS THE ISLAND AT THIS TIME. LESS MOISTURE IS
EXPECTED TODAY BUT DAYTIME HEATING COULD GENERATE AFTERNOON
ISOLATED SHOWERS/THUNDERSTORMS ACROSS THE INLAND PORTIONS OF THE
ISLAND AND POSSIBLY ALONG THE ATLC COAST THROUGH TUE.

ATLANTIC OCEAN...

THE UPPER-LEVEL RIDGE OVER THE NW CARIBBEAN EXTENDS A RIDGE AXIS
ACROSS CUBA NEAR 21N79W TO BEYOND 32N79W COVERING THE W ATLANTIC
W OF 70W. A CUTOFF UPPER-LOW IS JUST TO THE E NEAR 25N66W AND IS
SUPPORTING A 1010 MB LOW DESCRIBED IN THE SPECIAL FEATURES
ABOVE. T.D. IDA AND THE TROPICAL WAVE ARE ALSO DISCUSSED IN THE
SECTIONS ABOVE. TO THE S...A SECOND UPPER-LEVEL LOW IS CENTERED
JUST E OF THE LEEWARD ISLANDS NEAR 16N60W COVERING THE W
TROPICAL ATLANTIC S OF 23N BETWEEN 50W-60W. A WEAK SURFACE RIDGE
COVERS THE E ATLANTIC E OF 42W ANCHORED BY A 1021 MB HIGH NEAR
37N17W. LOOKING AHEAD...EXPECT FOR THE 1010 MB LOW E OF BAHAMAS
TO MOVE SLOWLY NW THROUGH EARLY NEXT WEEK. HIGH PRESSURE WILL
START TO BUILD IN FROM THE NE BY MIDWEEK.

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

$$

ERA
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