[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 270546
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SAT APR 27 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA NEAR 9N13W
TO 5N19W. THE ITCZ BEGINS NEAR 4N20W AND CONTINUES ALONG 3N30W
2N40W TO 1N45W. A CLUSTER OF NUMEROUS STRONG CONVECTION IS
MOVING OFF THE COAST OF AFRICA FROM 3N-9N BETWEEN 9W-14W.
ISOLATED SHOWERS ARE WITHIN 75 NM EITHER SIDE OF THE ITCZ AXIS.

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER LEVEL RIDGING CONTINUES ACROSS THE GULF OF MEXICO
SUPPORTING SURFACE RIDGING ACROSS THE AREA EXTENDING FROM A 1031
MB HIGH CENTERED NEAR 38N74W. E TO SE SURFACE WINDS OF 5-15 KT
SPREAD ACROSS THE GULF AND AROUND THE RIDGE ALONG WITH MOSTLY
CLEAR SKIES. A WEAK SURFACE TROUGH IS INLAND ALONG THE W YUCATAN
PENINSULA EXTENDING FROM 20N90W TO 16N91W. SCATTERED SHOWERS ARE
POSSIBLE IN THE BAY OF CAMPECHE S OF 21N BEING ENHANCED BY THE
SURFACE TROUGH AND MOISTURE ADVECTION FROM THE E PACIFIC OCEAN.
LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS AS SURFACE
RIDGING REMAINS THE DOMINANT FEATURE. A COLD FRONT IS EXPECTED
TO ENTER THE NW GULF SUNDAY MORNING.

CARIBBEAN SEA...
BROAD UPPER RIDGING ACROSS THE GULF OF MEXICO EXTENDS TO THE
WESTERN CARIBBEAN. MOISTURE ADVECTION FROM THE E PACIFIC OCEAN
BY NEARLY WESTERLY FLOW IS ENHANCING RAINSHOWERS IN THE YUCATAN
CHANNEL AND WITHIN 100 NM FROM THE SOUTHERN COASTLINE OF CUBA.
AN UPPER LEVEL TROUGH COVERS THE REMAINDER OF THE CARIBBEAN.
VERY DRY AIR IN THE MIDDLE LEVELS ASSOCIATED TO THIS TROUGH IS
PROVIDING MOSTLY FAIR CONDITIONS AT THE SURFACE WITH ONLY A FEW
PATCHES OF POSSIBLE ISOLATED SHOWERS WITHIN 100 NM S OF LA
HISPANIOLA AS WELL AS WITHIN 100 NM NE OF THE HONDURAS
COASTLINE. ISOLATED SHOWERS ARE ALSO IN THE FAR SE CORNER OF THE
BASIN. A MUCH LARGER AREA OF SCATTERED SHOWERS IS EAST OF THE
WINDWARD ISLANDS ASSOCIATED WITH MOIST SOUTHWESTERLY FLOW ALOFT
AROUND THE UPPER TROUGH. THIS AREA OF MOIST CONDITIONS EAST OF
THE ISLANDS MAY DRIFT WEST OVER THE WEEKEND POSSIBLY BRINGING
HEAVY RAINFALL TO SOME OF THE SOUTHERN LESSER ANTILLES.
TRADEWIND FLOW OF 10-15 KT DOMINATES THE CENTRAL AND EASTERN
CARIBBEAN WHILE WINDS UP TO 25 KT SPREAD OVER THE WESTERN AND
SOUTHERN REGIONS OF THE BASIN DUE TO A TIGHTER PRESSURE
GRADIENT.

ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH EXTENDS OFF THE EASTERN SEABOARD ALONG 66W
SUPPORTING A COLD FRONT N OF THE DISCUSSION AREA AND A
PREFRONTAL SURFACE TROUGH ALONG 30N66W 28N68W. SCATTERED SHOWERS
ARE WITHIN 190 NM E OF THE TROUGH N OF 27N. AN INVERTED SURFACE
TROUGH IS TO THE SOUTH FROM 25N69W TO 20N69W. ISOLATED SHOWERS
ARE POSSIBLE ALONG THIS SECOND SURFACE TROUGH. FARTHER EAST AN
UPPER LEVEL LOW LOCATED NEAR 36N34W IS SUPPORTING A 1005 MB
SURFACE LOW NEAR 34N32W WITH AN ASSOCIATED COLD FRONT THAT
ENTERS THE DISCUSSION AREA ALONG 30N26W 24N32W TO 23N42W.
SCATTERED SHOWERS ARE WITHIN 100 NM E OF THE COLD FRONT S OF 28N
BETWEEN 27W AND 42W.

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

$$
NR


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