[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 202350
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST WED JAN 20 2010

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N09W 4N23W CROSSING THE EQUATOR
NEAR 42W AND INTO NE BRAZIL NEAR 1S46W. ISOLATED MODERATE
CONVECTION IS FROM THE EQUATOR TO 5N BETWEEN 21W-32W.

...DISCUSSION...

GULF OF MEXICO...
SOUTHERLY SURFACE FLOW DOMINATES ACROSS THE GULF THIS EVENING
BETWEEN A SURFACE RIDGE ACROSS THE W ATLC AND FLORIDA PENINSULA
AND A DEVELOPING AREA OF LOW PRESSURE ACROSS THE SOUTHERN U.S.
PLAINS. ACCORDING TO THE LATEST SHIP AND BUOY OBSERVATIONS
ACROSS THE GULF...S-SE WINDS ARE REACHING UP TO 20 KT ACROSS THE
THE GULF W OF 90W. ALOFT...AN WEAK UPPER LEVEL SHORTWAVE
DISTURBANCE IS QUICKLY MOVING ACROSS THE SE CONUS GENERATING
SCATTERED SHOWERS AND TSTMS N OF 28N. THE NEXT UPPER LEVEL
SHORTWAVE TROUGH IS CURRENTLY MOVING ACROSS WESTERN TEXAS AND IS
FORECAST TO INTRODUCE A FRONTAL TROUGH TO THE NW GULF WATERS
EARLY THURSDAY. AS THE FRONTAL TROUGH DAMPERS OUT AS IT MOVES
EASTWARD...SE FLOW WILL INCREASE ONCE AGAIN ACROSS THE WESTERN
GULF WITH THE NEXT COLD FRONT TO MOVE OFF THE TEXAS COAST LATE
SATURDAY.

CARIBBEAN SEA...
MOST OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER
UNDER THE INFLUENCE OF DRY AIR AND SUBSIDENCE ALOFT. UPPER LEVEL
TROUGHING COVERS THE NW CARIBBEAN WITH AXIS FROM WESTERN CUBA TO
HONDURAS AND EL SALVADOR WHILE AN UPPER LEVEL RIDGE IS ACROSS
THE REMAINDER OF THE CARIBBEAN WITH AXIS EXTENDING FROM NORTHERN
VENEZUELA NE INTO THE CENTRAL ATLC NEAR 25N45W. WHILE THE UPPER
LEVELS OF THE ATMOSPHERE ACROSS THE CARIBBEAN ARE RELATIVELY
STABLE...A COUPLE OF LOW-LEVEL SHALLOW BOUNDARIES EXIST OVER
PORTIONS OF THE BASIN. FIRST...A SURFACE TROUGH EXTENDS FROM THE
SW NORTH ATLC ACROSS HISPANIOLA TO JAMAICA. ISOLATED SHOWERS ARE
FOCUSED WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. FARTHER
EAST...ANOTHER SURFACE TROUGH IS ANALYZED FROM 19N60W ACROSS THE
LEEWARD ISLANDS TO 15N64W. ISOLATED SHOWERS ARE OCCURRING MAINLY
N OF 16N BETWEEN 59W-63W. FRESH TO STRONG TRADEWINDS CONTINUE
ELSEWHERE ACROSS THE CARIBBEAN WITH THE STRONGEST WINDS LOCATED
OFF THE COAST OF COLOMBIA REACHING GALE FORCE FROM 11N-15N
BETWEEN 72W-77W AND SEAS REACHING 14 FT.

ATLANTIC OCEAN...
A WEAK SURFACE RIDGE COVERS THE FAR SW NORTH ATLC ANCHORED BY A
1018 MB HIGH CENTERED NEAR 27N77W WHICH IS PROVIDING GENERALLY
FAIR WEATHER ACROSS THE BAHAMAS AND AREAS W OF 70W. FARTHER
EAST...A WEAKNESS IN THE SUB-TROPICAL RIDGE IS NOTED AS A COLD
FRONT ENTERS THE DISCUSSION AREA NEAR 32N40W AND CONTINUES SW TO
24N58W AND CONTINUES AS A STATIONARY FRONT TO 21N66W. THE
BOUNDARY WEAKENS FURTHER AS A SURFACE TROUGH IS ANALYZED TO
HISPANIOLA AND INTO THE WESTERN CARIBBEAN NEAR JAMAICA.
SCATTERED SHOWERS ARE WITHIN 90 NM E OF THE FRONTS AND WITHIN
150 NM W OF THE FRONTS ACROSS THE CENTRAL ATLC AND PORTIONS OF
THE SW NORTH ATLC. A SECONDARY SURFACE TROUGH FOLLOWS BEHIND THE
COLD FRONT ANALYZED FROM 31N47W TO 28N55W. THESE BOUNDARIES ARE
ALL SUPPORTED BY BROAD UPPER LEVEL TROUGHING OVER THE CENTRAL
NORTH ATLC WITH AN AXIS THAT EXTENDS FROM 40N33W TO 31N48W. OVER
THE TROPICAL ATLC...A SHEAR LINE IS ALONG 15N50W 15N55W TO
18N59W. THIS LINE OF CONVERGENT SURFACE WINDS IS GENERATING
SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THE SHEAR LINE.
THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A
SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED OVER THE
MADEIRA ISLANDS NEAR 33N16W. THE RIDGE AXIS EXTENDS FROM THE
HIGH CENTER THROUGH 25N35W TO NORTH OF THE SHEAR LINE NEAR
21N52W.

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

$$
HUFFMAN


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