[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 062354
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST TUE MAR 06 2012

CORRECTED FOR PRECIPITATION INFORMATION IN NORTHWESTERN
COLOMBIA NEAR THE PANAMA BORDER...AND FOR THE
ATLANTIC OCEAN SECTION

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 2315 UTC.

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

THE MONSOON TROUGH EXTENDS SW FROM THE AFRICAN COAST AT 11N15W
TO 04N22W WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN
ITCZ WHICH CONTINUES SW THROUGH 00N37W TO THE COAST OF S AMERICA
AT 02S43W. ISOLATED MODERATE CONVECTION IS NOTED S OF 07N TO THE
EQUATOR E OF 14W. LOCALLY BROKEN LOW AND MID LEVEL CLOUDS WITH
EMBEDDED SHOWERS ARE OBSERVED WITHIN 120 NM EITHER SIDE OF A
LINE FROM 03N17W TO 00N27W TO 04N33W TO 04N37W.

...DISCUSSION...

THE GULF OF MEXICO...
AN UPPER LEVEL TROUGH EXTENDS S ACROSS THE EASTERN GULF OF
MEXICO WHILE AN UPPER RIDGE IS BUILDING N ACROSS THE WESTERN
GULF. THE UPPER TROUGH IS ACCOMPANIED BY VERY DRY AIR ALOFT AND
IS SUPPRESSING CLOUDINESS AND CONVECTION OVER THE NE GULF...N OF
26N E OF 85W. AN UPPER LEVEL MOISTURE PLUME ORIGINATING IN THE
PACIFIC IS STREAMING NE ACROSS NORTHERN MEXICO...TURNING E
ACROSS THE UPPER RIDGE WITH THE MOISTURE THEN FANNING OUT OVER
TEXAS AND LOUISIANA...WITH THIN CIRRUS NOW STREAMING E ACROSS
THE EXTREME NW GULF. AT THE LOW LEVELS A RIDGE DISSECTS THE GULF
FROM N FLORIDA TO THE BAY OF CAMPECHE. LOW LEVEL CLOUDS
ASSOCIATED WITH A FRONTAL TROUGH ARE MOVING N OVER THE SE GULF.
LOCALLY OVERCAST LOW LEVEL CLOUDS...LIKELY WITH EMBEDDED
SHOWERS...ARE WITHIN 100 NM OF THE MEXICAN COAST FROM THE BAY OF
CAMPECHE AT 18N94W TO NEAR 24.5N98W...AND ARE ALSO MOVING SLOWLY
N WITH TIME. AN PATCH OF FAIR-WEATHER STRATOCUMULUS CLOUDS IS
OBSERVED OVER THE CENTRAL GULF AND ALSO MOVING SLOWLY NW.

THE CARIBBEAN SEA...
AN UPPER TROUGH IS AMPLIFYING SE OVER THE NW CARIBBEAN AND IS
ACCOMPANIED BY VERY DRY AIR ALOFT. A COUPLE OF COLD FRONTS HAVE
WEAKENED TO SHEAR LINES EXTENDING E TO W ACROSS THE N-CENTRAL
AND NW CARIBBEAN...AND ARE ACCOMPANIED BY LOCALLY BROKEN LOW AND
MID LEVELS CLOUDS THAT ARE MOVING WESTWARD IN THE FAIRLY STRONG
NE LOW LEVEL FLOW. ONE SHEAR LINE EXTENDS FROM HISPANIOLA TO
JAMAICA TO THE E GULF OF HONDURAS WHILE A SECOND SHEAR LINE
EXTENDS ACROSS CENTRAL CUBA TO THE YUCATAN PENINSULA. THE DRY
AIR ALOFT IS SUPPRESSING ASSOCIATED CONVECTION TO EMBEDDED LIGHT
SHOWERS. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY AN UPPER
RIDGE ALOFT WITH STRONG WESTERLIES. TRADE WIND CUMULUS IS
OBSERVED RACING W ACROSS THE NE CARIBBEAN. THE TRADES ARE
ENHANCED ALONG THE NW COAST OF COLOMBIA WITH A 30 TO 35 KT GALE
WARNING IN EFFECT FROM 11N TO 13N BETWEEN 73W AND 79W AND
EXPECTED TO PERSIST THROUGH THU BUT SPREAD N TO ALONG 15N WITH
SEAS BUILDING TO 19 FT.

THE ATLANTIC OCEAN...
AN UPPER TROUGH IS MOVING OFF THE EASTERN SEABOARD OF THE CONUS
AND EXTENDS S OVER THE NW BAHAMAS AND IS ACCOMPANIED BY VERY DRY
UPPER AIR. A UPPER RIDGE DISSECTS THE CENTRAL ATLANTIC AND
EXTENDS NE FROM THE CARIBBEAN TO AN UPPER ANTICYCLONE AT 35N46W.
A NARROW BAND OF UPPER MOISTURE IS STREAMING NE ALONG THE NW
PERIPHERY OF THIS RIDGE...ROUGHLY WITHIN 75 NM EITHER SIDE OF A
LINE FROM 24N75W TO BEYOND 32N57W. IMMEDIATELY TO THE SE OF THIS
RIDGE...IS AN UPPER TROUGH THAT DOMINATES THE UPPER LEVELS OF
THE EASTERN ATLANTIC...AND EXTENDS SW THROUGH THREE LARGE UPPER
CYCLONES. THE EASTERNMOST DEEP LAYERED CYCLONE IS LOCATED OVER
NORTHERN AFRICA...ANOTHER DEEP LAYERED CYCLONE IS OVER THE
CENTRAL ATLANTIC AND ANALYZED AS 1023 MB AT THE SURFACE AT
30N32W...AND THE SOUTHERNMOST CYCLONE IS ALOFT AT 15N53W WITH
THE UPPER TROUGH CONTINUING SW TO BASE OVER THE DEEP TROPICS AT
08N59W. CLOUDINESS AND CONVECTION IS ENHANCED WITHIN 360 NM OVER
THE NE AND WITHIN 90 NM OVER THE SW SEMICIRCLES OF THE CENTRAL
ATLANTIC CYCLONE. ASSOCIATED UPPER MOISTURE EXTENDS NE FROM THE
THIS CONVECTION TO OVER THE CANARY ISLANDS. A BROAD UPPER RIDGE
DOMINATES THE SE PORTION OF THE N ATLANTIC WITH A VERY DENSE
MOISTURE PLUME...ORIGINATING OVER S AMERICA...STREAMING NE ALONG
THE NW PERIPHERY OF RIDGE...ALL WITHIN 480 NM EITHER SIDE OF A
LINE FROM 01N50W TO 14N35W TO ACROSS AFRICA AT 18N16W.

AT THE LOW LEVELS...TWO COLDS FRONTS ARE WEAKENING FROM NEAR
32N60W TO ACROSS THE SE AND NW BAHAMAS RESULTING IN A BROAD AREA
OF LOCALLY OVERCAST LOW AND MID LEVELS CLOUDS AND EMBEDDED
SHOWERS. TO THE NW OF FRONTAL CLOUDINESS...LOCALLY BROKEN COLD
AIR STRATOCUMULUS CLOUDS ARE OBSERVED TO THE E COAST OF THE
CONUS.

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

$$
NELSON






This weather bulletin was brought to you by:
www.nashvilleweather.net