[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 171053
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT APR 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1045 UTC...

...ITCZ...

FROM THE CENTRAL COAST OF LIBERIA NEAR 6N10W...WESTWARD ALONG
4N20W 5N30W 3N40W EQ50W. ISOLATED MODERATE CONVECTION IS WITHIN
100 NM EITHER SIDE OF THE AXIS WEST OF 20W.

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL SHORTWAVE OVER THE
NORTHERN TIP OF THE YUCATAN PENINSULA SUPPORTING A MID LEVEL LOW
SPINNING NEAR 21N89W. THIS FEATURE IS PRODUCING DEEP CONVECTION
AT SURFACE FROM 20N TO 24N BETWEEN 89W AND 92W. ALSO...THIS
SYSTEM SUPPORTS A SURFACE TROUGH OVER THE YUCATAN CHANNEL ALONG
24N88W 22N86W INTO THE NORTHWEST CARIBBEAN BASIN. THIS TROUGH IS
BRINGING MULTIPLE SCATTER MODERATE TO HEAVY SHOWERS TO WESTERN
CUBA. AS THIS UPPER LEVEL FEATURE MOVES EASTWARD THROUGH THE
WEEKEND...EXPECT A SURFACE LOW TO DEVELOP ALONG THE FRONTAL
TROUGH OVER THE SOUTH AND SOUTHEAST GULF BRINGING ADDITIONAL
CONVECTION TO THIS REGION OVER THE NEXT 24 HOURS. A 1020 MB HIGH
OVER THE WESTERN ATLANTIC CONTINUES PUSH LOW LEVEL MOISTURE AND
SHOWERS TO THE SOUTHERN FLORIDA PENINSULA. THE WESTERN ATLANTIC
HIGH WILL CONTINUE TO MOVE EASTWARD OVER THE NEXT 24 HOURS...AS
A WEAK FRONTAL BOUNDARY SKIRTS THE NORTHERN WATERS AND COASTAL
PLAIN.

CARIBBEAN SEA...
AN UPPER LEVEL SHORTWAVE IS OVER THE NORTHERN TIP OF THE YUCATAN
PENINSULA SUPPORTING A MID LEVEL LOW SPINNING NEAR 21N89W. A
TROUGH ENTERS THE NORTHWEST BASIN THROUGH THE YUCATAN CHANNEL
ALONG 24N88W 22N86W 20N86W 18N86W 16N87W. THIS FEATURE IS
SUPPORTING NUMEROUS SHOWERS AND SCATTERED TSTMS OVER THE FAR
NORTHWEST BASIN NORTH OF 15N WEST OF 80W. COMPUTER MODELS
INDICATE THIS AREA OF CONVECTION WILL MOVE EASTWARD AFFECTING
THE CUBA AND WESTERN CARIBBEAN SEA NORTH OF 14N WEST OF 76W.
ELSEWHERE ACROSS THE CENTRAL AND EASTERN BASIN...NORTHEAST WINDS
OVER THE NORTH-NORTHEAST BASIN CONTINUE TO FEED ATLANTIC
MOISTURE AND ISOLATED SHOWERS OVER PUERTO RICO AND HISPANIOLA.
THE REMAINDER OF THE BASIN IS EXPERIENCING TRADES IN THE 15 TO
20 KT RANGE THIS UNDER GENERALLY FAIR SKIES.

ATLANTIC OCEAN...
A 1021 MB SURFACE HIGH OVER THE FAR WESTERN ATLANTIC NEAR 27N66W
CONTINUES TO BRING FAIR WEATHER WEST OF 62W. HOWEVER...A FEW
ISOLATED SHOWERS EMBEDDED WITHIN EASTERLY FLOW CONTINUE TO
IMPACT THE CENTRAL AND NORTHERN BAHAMAS AS WELL AS PORTIONS OF
THE SOUTHERN FLORIDA PENINSULA. BROAD AND ELONGATED SUBTROPICAL
JETSTREAM FLATTENS ACROSS THE ATLANTIC WITH CENTRAL AXIS ALONG
25N. WITHIN THIS UPPER LEVEL FEATURE LIES A STRONG JETSTREAK
COVERING THE WESTERN AND CENTRAL ATLANTIC FROM 34W TO 68W ALONG
THE SAME LATITUDE AXIS. THIS FEATURE IS ENHANCING AN OCCLUDED
UPPER LEVEL LOW NEAR 35N43W. THE UPPER LEVEL LOW SUPPORTS A PAIR
OF SURFACE LOW PRESSURE SYSTEMS NEAR 35N46W AND 39N45W. SURFACE
BOUNDARIES FROM THESE TWO SURFACE LOWS EXTEND INTO THE
DISCUSSION AREA. A COLD FRONT ENTERS NEAR 32N36W TO A WEAK 1011
MB LOW CENTERED NEAR 22N43W. THEN...IT CONTINUES TO NEAR
17N48W...WHERE IT BECOMES A SURFACE TROUGH THAT EXTENDS TO THE
EASTERN COAST OF VENEZUELA NEAR 10N62W. SCATTERED SHOWERS ARE
WITHIN 200 NM EAST OF THE COLD FRONT AND WITHIN 200 NM EITHER
SIDE OF THE SURFACE TROUGH. A SECONDARY SURFACE TROUGH IS NW OF
THE LEADING COLD FRONT AND EXTENDS FROM 32N41W TO 25N51W. A
SHEAR LINE CONTINUES WEST TO NEAR 25N62W. ISOLATED SHOWERS ARE
WITHIN 60 NM EITHER SIDE OF THE BOUNDARY. FARTHER EAST...A 1018
MB HIGH IS CENTERED NEAR 25N25W AND EXTENDS SURFACE RIDGING AND
GENERALLY FAIR WEATHER OVER THE REMAINDER OF THE EASTERN
ATLC...INCLUDING THE CAPE VERDE ISLANDS.

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

$$

GARCIA




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