[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 182341
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST MON FEB 18 2013

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.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL
ATLC THROUGH SIERRA LEONE TO 03N20W WHERE THE ITCZ CONTINUES
TO 1N35W THEN S OF THE EQUATOR NEAR 42W TO NE BRAZIL. SMALL
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE
NOTED N OF 1N BETWEEN 2W AND 10W AND FROM 5N TO 7N BETWEEN 11W
AND 20W. SCATTERED MODERATE CONVECTION CAN BE FOUND FROM THE
EQUATOR TO 3N BETWEEN 40W AND 50W.

...DISCUSSION...

GULF OF MEXICO...
A SURFACE RIDGE DOMINATES THE GULF WATERS AND THE STATE OF
FLORIDA ANCHORED BY A 1031 MB HIGH LOCATED ALONG THE COAST OF
NORTH CAROLINA. THIS SYSTEM EXTENDS A RIDGE AXIS SW TO THE BAY
OF CAMPECHE. SLY RETURN FLOW HAS ESTABLISHED OVER THE WESTERN
GULF AND THE MOST RECENT ASCAT PASS SHOWED WINDS OF 20-25 KT W
OF 94W. THE HIGH PRES CENTER WILL CONTINUE TO MOVE EWD ACROSS
THE WESTERN ATLC ALLOWING A COLD FRONT TO MOVE INTO THE NW GULF
EARLY TUE. THE FRONT WILL STALL FROM CENTRAL FLORIDA TO S TEXAS
EARLY WED...THEN WILL SHIFT N AS A WARM FRONT WED NIGHT AND THU.
ALOFT...AN UPPER TROUGH IS DIGGING S OVER THE CENTRAL PLAIN
STATES TO TEXAS AMPLIFYING AN UPPER RIDGE OVER THE E CONUS FROM
THE N GULF COAST TO THE GREAT LAKES. THIS PATTERN IS GIVING THE
GULF REGION NEAR ZONAL WESTERLY FLOW. REMNANT COLD AIR
STRATOCUMULUS CLOUDS ARE STILL NOTED OVER THE EASTERN GULF WHILE
DOPPLER RADAR SHOWS SCATTERED SHOWERS AND TSTMS NEAR THE UPPER
TEXAS COAST.

CARIBBEAN SEA...
A WEAKENING STATIONARY FRONT EXTENDS FROM HISPANIOLA TO THE SW
CARIBBEAN NEAR 11N82W. THIS FRONT WILL DISSIPATE TONIGHT. HIGH
PRES IN THE WAKE OF THE FRONT IS SUPPORTING FRESH TO STRONG
TRADE WINDS ACROSS THE BASIN WITH THE STRONGEST WINDS OF 25 TO
30 KT NEAR THE COAST OF COLOMBIA. W OF THE FRONTAL BOUNDARY...A
WINDSAT PASS SHOWED NE WINDS OF 20 TO 25 KT WITH SOME WIND BARBS
OF 30 KT IN LEE OF EASTERN CUBA. FRESH TO STRONG TRADE WINDS
WILL PERSIST THROUGH WED THEN DIMINISH ACROSS THE EASTERN AND
WESTERN CARIBBEAN. HOWEVER...FRESH TO STRONG WINDS WILL PERSIST
ACROSS THE CENTRAL CARIBBEAN MOST OF THE WEEK. A VERY COLD NIGHT
WAS REPORTED BY THE CUBAN WEATHER SERVICE WITH TEMPERATURES
BELOW 10 DEGREES CELSIUS IN PARTS OF WEST-CENTRAL CUBA. THE
COLDEST TEMPERATURE WAS REPORTED IN BAINOA WITH 4.0 DEGREES
FOLLOWED BY TAPASTE WITH 4.9 DEGREES WHILE IN THE CITY OF HAVANA
THE MERCURY DROPPED TO 11.9 DEGREES CELSIUS. A WARMING TREND IS
EXPECTED ACROSS THE REGION AS HIGH PRES...CURRENTLY LOCATED
ALONG THE COAST OF NORTH CAROLINA...MOVES EWD AND WINDS VEER TO
THE E AND SE HELPING THE TEMPERATURE TO RISE DURING THE
REMAINDER OF THE WORK WEEK. WATER VAPOR SATELLITE IMAGERY
CONTINUES TO SHOW VERY STRONG SUBSIDENCE AND DRY STABLE AIR
ALOFT ACROSS MOST OF THE BASIN BUT MAINLY ACROSS THE SOUTH-
CENTRAL CARIBBEAN. SHALLOW MOISTURE EMBEDDED IN THE TRADE WIND
FLOW WILL MOVE ACROSS THE REGION PRODUCING ISOLATED TO SCATTERED
PASSING SHOWERS. THE SAN JUAN DOPPLER RADAR SHOWS SOME OF THESE
PATCHES OF MOISTURE CROSSING JUST SOUTH OF PUERTO RICO AND NEAR
THE VIRGIN ISLANDS.

ATLANTIC OCEAN...
A DEEP LAYER TROUGH COVERS THE W ATLC W OF 60W. THIS TROUGH
SUPPORTS A STRONG COLD FRONT THAT ENTERS THE DISCUSSION AREA
NEAR 31N52W EXTENDING SW TO NEAR 22N67W WHERE IT BECOMES
STATIONARY CROSSING HISPANIOLA INTO THE CARIBBEAN SEA.
SCATTEROMETER DATA INDICATE FRESH TO STRONG WINDS W OF THE
FRONT...PARTICULARLY S OF 24N ACROSS THE SE BAHAMAS INTO THE
WINDWARD PASSAGE. A WIDE BAND OF MULTILAYERED CLOUDS WITH
EMBEDDED SHOWERS IS ASSOCIATED WITH THE FRONT FORECAST TO
GRADUALLY DISSIPATE THROUGH WED AS IT CONTINUES TO MOVES ESE
ACROSS THE CENTRAL ATLC. VISIBLE SATELLITE IMAGERY REVEALS A
LARGE AREA OF COLD AIR STRATOCUMULUS CLOUDS WEST OF THE FRONTAL
BOUNDARY TO THE COAST OF FLORIDA. E OF THE FRONT...A 1027 MB
HIGH PRES IS CENTERED NEAR 29N39W AND IS EXPECTED TO SLOWLY MOVE
SE WHILE SLIGHTLY WEAKENING. THIS SYSTEM EXTENDS A RIDGE OVER
THE REMAINDER OF THE E AND CENTRAL ATLC. FRESH TO STRONG TRADE
WINDS ARE NOTED ON THE SOUTHERN PERIPHERY OF THE RIDGE.
ALOFT...AN UPPER RIDGE COVERS THE CENTRAL ATLC N OF 20N. AN
ELONGATED UPPER LEVEL TROUGH IS OVER THE E ATLC AND EXTENDS FROM
31N13W SW THEN W ALL THE WAY TO NEAR BARBADOS IN THE WINDWARD
ISLANDS. STRONG SWLY FLOW IS SEEN ON THE SOUTH SIDE OF THE
TROUGH AXIS. THESE WINDS INCREASE TO 90-110 KT OVER WESTERN
AFRICA. THE NEXT COLD FRONT WILL MOVE INTO THE NW PORTION OF THE
FORECAST AREA EARLY WED.

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

$$
GR






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