[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121146
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST THU JAN 12 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 THROUGH
1115 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N11W TO
07N18W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
07N18W TO THE EQUATOR NEAR 41W THEN TO 01S46W. ISOLATED MODERATE
CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 33W-40W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL TROUGH IS LOCATED OVER THE EASTERN GULF THIS
MORNING WITH ONE SHORTWAVE WELL NORTH OF THE REGION OVER THE
MID-ATLC STATES AND ANOTHER SHORTWAVE LOCATED OVER THE EASTERN
GULF NEAR 27N84W. BOTH OF THESE SHORTWAVES ARE SUPPORTING A COLD
FRONT ANALYZED ACROSS THE SOUTHERN FLORIDA PENINSULA AND INTO
THE SE GULF NEAR 26N81W THEN SW TO WESTERN CUBA NEAR 22N85W. THE
FRONT CONTINUES TO WEAKEN WITH ISOLATED SHOWERS OCCURRING EAST
OF THE FRONT OVER PORTIONS OF THE FLORIDA STRAITS. THE REMAINDER
OF THE GULF IS UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE
ANCHORED BY A 1014 MB HIGH CENTERED NEAR 22N88W WITH GENERALLY
CLEAR SKIES NOTED ON SATELLITE IMAGERY. HOWEVER...THE NEXT UPPER
LEVEL SHORTWAVE CONTINUES TO PROGRESS ACROSS THE SOUTHERN PLAINS
AND AS OF 12/0900 UTC SUPPORTS A STRONGER COLD FRONT WHICH IS
ANALYZED OVER THE EXTREME NW GULF FROM 30N93W TO THE TEXAS COAST
NEAR 27N97W. THE FRONT HAS INTRODUCED STRONG NORTHERLY WINDS AND
IS FORECAST TO SWEEP ACROSS THE ENTIRE GULF BY FRIDAY MORNING.
THEREAFTER...HIGH PRESSURE IS THEN EXPECTED TO DOMINATE THROUGH
THE UPCOMING WEEKEND.

CARIBBEAN SEA...
AN UPPER LEVEL RIDGE AXIS EXTENDS FROM THE TROPICAL NORTH ATLC
NEAR 08N56W NW TO OVER HISPANIOLA NEAR 20N72W. WATER VAPOR
IMAGERY INDICATES MOSTLY DRY AIR AND SUBSIDENCE IS LOCATED N OF
10N AND IS PROVIDING AN OVERALL STABLE ATMOSPHERE ACROSS THE
CARIBBEAN THIS MORNING. SHORTWAVE INFRARED SATELLITE IMAGERY
SHOWS TRANQUIL CONDITIONS PERSIST WITH E-NE TRADES IN THE RANGE
OF 10 TO 20 KT...WITH HIGHER WINDS EXPECTED IN THE VICINITY OF
THE COAST OF COLOMBIA. THE ONLY EXCEPTION TO THE FAIR WEATHER
BASIN WIDE IS LOCATED OVER THE EXTREME NW PORTION. A DISSIPATING
STATIONARY FRONT EXTENDS FROM WESTERN CUBA NEAR 22N85W TO THE
YUCATAN PENINSULA COAST NEAR 20N87W. SATELLITE IMAGERY INDICATES
THAT ANY POSSIBLE ISOLATED SHOWER ACTIVITY IS OCCURRING NORTH OF
THE YUCATAN CHANNEL WITHIN THE SE GULF OF MEXICO WATERS.

ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE IS LOCATED OVER THE SW NORTH ATLC WITH
RIDGE AXIS EXTENDING FROM OVER HISPANIOLA NEAR 20N70W TO BEYOND
32N64W. ON THE WESTERN PERIPHERY OF THE RIDGE...MOIST
SOUTHWESTERLY UPPER LEVEL FLOW IS NOTED BETWEEN THE RIDGE AND
TROUGHING ACROSS THE SE CONUS AND EASTERN SEABOARD. THIS TROUGH
SUPPORTS A COLD FRONT ANALYZED FROM COASTAL NORTH CAROLINA NEAR
35N76W TO 32N76W THEN SW TO THE FLORIDA COAST NEAR 27N80W.
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 90 NM
EITHER SIDE OF A LINE FROM 32N73W TO 25N78W. FARTHER EAST...THE
UPPER LEVEL RIDGING SUPPORTS A 1022 MB HIGH CENTERED NEAR
32N58W. HOWEVER...A NORTH-CENTRAL ATLC UPPER LEVEL TROUGH
SUPPORTS A COLD FRONT DRAPED INTO THE DISCUSSION AREA THAT
PENETRATES THE SOUTHEASTERN PERIPHERY OF THE SURFACE RIDGE. THE
COLD FRONT IS ANALYZED FROM 32N44W TO 27N58W. A PRE-FRONTAL
TROUGH IS ALSO SE OF THE FRONT FROM 29N47W TO 24N52W WITH
ISOLATED SHOWERS OCCURRING WITHIN 150 NM EAST OF THE SURFACE
TROUGH AND COLD FRONT N OF 28N. THE LAST SURFACE FEATURE OF
IMPORTANCE THIS MORNING IS A SURFACE TROUGH EXTENDING INTO THE
DISCUSSION AREA NEAR 32N36W TO 21N38W. WATER VAPOR IMAGERY SHOWS
THAT AN UPPER LEVEL TROUGH IS IN PLACE OVER THE SURFACE TROUGH
WITH AXIS ALONG 34W. ISOLATED SHOWERS ARE OCCURRING EAST OF THE
SURFACE TROUGH OVER THE AREA FROM 26N-32N BETWEEN 26W-33W AND IS
LIKELY ENHANCED DUE TO UPPER LEVEL DIFFLUENCE EAST OF THE UPPER
LEVEL TROUGH AXIS.

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

$$
HUFFMAN




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