[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 201719
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1630 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED FROM THE S IVORY COAST OF AFRICA NEAR
5N2W ALONG 5N18W 3N32W TO THE NE BRAZIL COAST NEAR EQ50W.
ISOLATED MODERATE CONVECTION IS FROM 2N-4N BETWEEN 26W-30W.

...DISCUSSION...

GULF OF MEXICO...
A SURFACE RIDGE ANCHORED BY A 1018 MB HIGH N OF TAMPA FLORIDA
NEAR 29N82W DOMINATES THE ERN GULF OF MEXICO TODAY PROVIDING
GENERALLY FAIR WEATHER ACROSS MUCH OF THE BASIN EXCEPT FOR SOME
ISOLATED SHOWERS/THUNDERSTORMS MOVING ACROSS SE LOUISIANA AND S
MISSISSIPPI INDICATED BY RADAR IMAGERY. ANTI-CYCLONIC SURFACE
FLOW IS AROUND THE RIDGE REACHING 20 KT ACROSS THE W AND MIDDLE
GULF. IN THE UPPER LEVELS...MAINLY ZONAL WLY FLOW ALOFT COVERS
THE BASIN ALONG WITH MODERATELY DRY AIR IN THE MID AND UPPER
LEVELS. EXPECT THE SURFACE RIDGE TO CONTINUE SHIFTING E AND
WEAKENING ALLOWING SLY RETURN FLOW TO INCREASE TODAY ACROSS THE
W AND MIDDLE GULF AHEAD OF THE NEXT COLD FRONT FORECAST TO MOVE
OFF THE TEXAS COAST EARLY TOMORROW.

THE CARIBBEAN SEA...
MOST OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER
TODAY UNDER THE INFLUENCE OF DRY AIR AND SUBSIDENCE ALOFT AROUND
AN UPPER LEVEL RIDGE WITH AXIS ALONG 55W. A NARROW SWATH OF
MODERATE MOISTURE EXTENDS ACROSS THE NW CARIBBEAN AROUND THE E
SIDE OF A BROAD UPPER LEVEL TROUGH THAT SUPPORTS A FRONTAL
BOUNDARY IN THE W ATLC CONTINUING TO N DOMINICAN REPUBLIC
NEAR 20N70W. A FEW ISOLATED SHOWERS ARE NOTED ACROSS CENTRAL
DOMINICAN REPUBLIC AND E OF JAMAICA DUE TO SURFACE CONVERGENCE
NEAR THE FRONT. A SURFACE TROUGH IS AHEAD OF THE FRONT BISECTING
PUERTO RICO FROM 20N63W TO 17N68W. ISOLATED SHOWERS ARE WITHIN
30 NM OF THE TROUGH AXIS. A SECOND SURFACE TROUGH EXTENDS ACROSS
THE LEEWARD ISLANDS FROM 18N60W TO 15N63W. ISOLATED SHOWERS ARE
WITHIN 90 NM OF THE AXIS N OF 17N. FRESH TO STRONG TRADEWINDS
CONTINUE ACROSS MUCH OF THE BASIN WITH THE STRONGEST WINDS OFF
THE COAST OF COLOMBIA WHERE THEY REACH GALE FORCE UP TO 35 KT
FROM 11N-15N BETWEEN 72W-77W. THE GALE FORCE WINDS ARE FORECAST
TO PERSIST FOR ANOTHER 24 HOURS.

THE ATLANTIC OCEAN...
A WEAK SURFACE RIDGE COVERS THE FAR SW N ATLC ANCHORED BY A 1018
MB HIGH N OF TAMPA FLORIDA...AND A 1019 MB HIGH S OF BERMUDA
NEAR 30N65W PROVIDING GENERALLY FAIR WEATHER ACROSS THIS PORTION
OF THE BASIN. IMMEDIATELY E...A DYING COLD FRONT ENTERS THE
DISCUSSION AREA NEAR 32N49W CONTINUING ALONG 28N58W TO 27N68W.
ISOLATED SHOWERS ARE ALONG THE FRONT AXIS. THE PRIMARY COLD
FRONT IS FARTHER E EXTENDING FROM A 980 MB LOW ENTERING THE
DISCUSSION AREA NEAR 32N41W CONTINUING SW ALONG 28N50W 25N59W
BECOMING STATIONARY TO NRN DOMINICAN REPUBLIC NEAR 20N70W.
SCATTERED SHOWERS ARE WITHIN 90 NM AHEAD OF THE FRONT AND 45 NM
BEHIND OF THE FRONT N OF 24N WITH ISOLATED SHOWERS WITHIN 30 NM
ELSEWHERE ALONG THE FRONT. A BROAD UPPER LEVEL
SHORTWAVE TROUGH WITH AXIS ALONG 70W SUPPORTS THE FRONTAL SYSTEM
ALONG WITH A NARROW SWATH OF MODERATE MID-UPPER LEVEL MOISTURE
EXTENDING FROM ERN CUBA TO THE NE. A SURFACE TROUGH IS E OF THE
FRONT FROM 20N63W TO 17N68W BISECTING PUERTO RICO. ISOLATED
SHOWERS ARE WITHIN 30 NM OF THE TROUGH AXIS. A SHEAR LINE
CONTINUES E OF THE NRN LESSER ANTILLES DEPICTING A LINE OF
CONVERGING WIND SPEEDS ALONG 17N46W 15N52W 17N59W. SCATTERED
SHOWERS ARE WITHIN 30 NM OF THE SHEAR AXIS BETWEEN 50W-59W.  AN
UPPER LEVEL RIDGE COVERS THE REMAINDER OF THE W AND CENTRAL ATLC
WITH AXIS ALONG 55W SUPPORTING A SURFACE RIDGE ANCHORED BY A
1027 MB HIGH N OF THE CANARY ISLANDS NEAR 34N15W. THE SURFACE
RIDGE IS PROVIDING GENERALLY AIR WEATHER ACROSS THE E ATLC.
HOWEVER...A NARROW UPPER LEVEL TROUGH WITH AXIS ALONG 32W IS
SUPPORTING SOME HIGH CLOUDS ACROSS THE AREA ALONG WITH ENHANCING
SOME MODERATE CONVECTION ALONG THE ITCZ.

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

$$
WALTON



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