[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 220547
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SUN JUL 22 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
SECTIONS OF SOUTH AMERICA...AND THE 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS OFF THE COAST OF W AFRICA ALONG 22W/23W S OF
19N MOVING W 15 KT. THE WAVE IS FAIRLY WELL ORGANIZED WITH
CYCLONIC TURNING COVERING A BROAD AREA. EARLIER QUIKSCAT PASS
CONFIRMED THE CYCLONIC CIRCULATION JUST SOUTH OF THE CAPE VERDE
ISLANDS. CONVECTION IS CONFINED TO THE ITCZ FROM 10N-12N BETWEEN
19W-25W.

TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES ALONG 58W S OF
20N MOVING W 15 KT. BROAD LOW LEVEL INVERTED-V SIGNATURE IS
NOTED WITH NO ASSOCIATED DEEP CONVECTION. SCATTERED SHOWERS ARE
FROM 14N-18N BETWEEN 55W-61W. LIGHT SHOWERS AHEAD OF THE WAVE
AXIS ARE ALREADY AFFECTING GUADELOUPE. THE WAVE IS FORECAST TO
ENTER THE CARIBBEAN SEA THIS MORNING. MOISTURE FROM THIS WAVE
SHOULD AFFECT THE UK/US VIRGIN ISLANDS AND PUERTO RICO SUNDAY
EVENING AND MONDAY.

TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 78W S OF 20N
MOVING W 15 KT. A BROAD LOW LEVEL INVERTED-V SIGNATURE IS NOTED
WITH WIDELY SCATTERED MODERATE CONVECTION PERSISTING OVER
JAMAICA AND ERN CUBA. THE WAVE IS ALSO GENERATING SCATTERED
SHOWERS AND TSTMS OVER THE SW CARIBBEAN FROM 11N-15N BETWEEN
76W-80W. THIS FEATURE WILL MOVE ACROSS CENTRAL AMERICA AND THE
NW CARIBBEAN TODAY...REACHING THE YUCATAN PENINSULA AND BELIZE
EARLY MONDAY.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 16N20W 9N30W 10N45W 10N63W. CLUSTERS
OF SCATTERED MODERATE CONVECTION ARE FROM 10N-12N BETWEEN
19W-25W...AND FROM 5N-10N BETWEEN 29W-41W.

...DISCUSSION...
GULF OF MEXICO...
WEAK PRESSURE PATTERN CHARACTERIZED BY WEAK RIDGING AND A WEAK
SFC TROUGH DOMINATES THE GULF. AS OF 0300 UTC...A 1017 MB HIGH
IS CENTERED OVER THE NW CORNER OF THE GULF NEAR 29N93W. A SFC
TROUGH GOES FROM 30N85W TO 26N88W. A STATIONARY FRONT LIES
ACROSS NORTH FLORIDA. THERE ARE ISOLATED SHOWERS ALONG THE
TROUGH AXIS. MOSTLY LIGHT AND VARIABLE WINDS ARE FOUND ACROSS
THE GULF. IN THE UPPER LEVELS...A DEEP LAYERED TROUGH OVER THE
EASTERN U.S. DIGS INTO THE EASTERN GULF. THE BASE OF THE TROUGH
REACHES THE NORTHERN YUCATAN PENINSULA AND WESTERN CUBA. WV
IMAGERY SHOWS A SMALL UPPER LEVEL LOW CENTERED NEAR 22N88W. THIS
TROUGH IS HELPING TO GENERATE SHOWERS AND TSTMS OVER THE STATE
OF FLORIDA AND WESTERN CUBA AND SUPPORTS THE AFOREMENTIONED
FRONT. A BROAD UPPER LEVEL HIGH IS INLAND OVER N/CENTRAL
MEXICO WITH THE UPPER RIDGE COVERING THE GULF W OF 90W...WHERE
NLY UPPER LEVEL WINDS ARE OBSERVED.

CARIBBEAN SEA...
RIDGE N OF AREA AND LOW PRES OVER COLOMBIA IS PRODUCING MODERATE
TRADE WINDS OF 15 TO 20 KT ACROSS THE SOUTH-CENTRAL CARIBBEAN. A
TROPICAL WAVE IS ALONG 78W PRODUCING CONVECTION IN THE AREA. SEE
ABOVE. SCATTERED MODERATE CONVECTION IS INLAND OVER PARTS OF
CENTRAL AMERICA AND NORTHERN COLOMBIA. ALOFT...THE UPPER LEVEL
LOW OVER THE SE GULF OF MEXICO IS PRODUCING SWLY FLOW OVER THE
NW CARIBBEAN SEA AND CUBA. AN UPPER LEVEL HIGH IS CENTERED
MIDWAY BETWEEN JAMAICA AND COLOMBIA WHILE ANOTHER UPPER LEVEL
HIGH IS OVER THE NE CARIBBEAN. UPPER DRY AIR COVERS MOST OF THE
E CARIBBEAN AND N VENEZUELA.

ATLANTIC OCEAN...
AS IS TYPICAL FOR THIS TIME OF THE YEAR...THE AZORES HIGH WITH A
1035 MB CENTER NEAR 38N45W DOMINATES MOST OF THE ATLANTIC OCEAN
WITH MAINLY FAIR WEATHER. ONLY PATCHES OF LOW/MID CLOUDS ARE
SEEN UNDER THE INFLUENCE OF THIS SYSTEM. PRES GRADIENT BETWEEN
THE AZORES HIGH AND A BROAD AREA OF LOW PRES JUST SOUTH OF THE
AZORES IS PRODUCING A SWATH OF 20 TO 25 KT NELY WINDS FROM 20N
TO 30N EAST OF 45W. ALOFT...A WELL DEFINED UPPER LEVEL LOW
IS NEAR 30N67W. A LARGE AREA OF CLOUDINESS AND SHOWERS...
EXTENDING FROM EASTERN HISPANIOLA AND THE SOUTHEASTERN BAHAMAS
NORTHEASTWARD INTO THE ATLANTIC IS ASSOCIATED WITH THIS
UPPER-LEVEL LOW. THIS SYSTEM REMAINS POORLY ORGANIZED BUT
ENVIRONMENTAL CONDITIONS COULD BECOME A LITTLE MORE FAVORABLE
FOR SOME DEVELOPMENT OVER THE NEXT DAY OR TWO. A CUT-OFF LOW IS
OVER THE CENTRAL ATLC NEAR 24N50W. A RIDGE EXTENDS FROM W AFRICA
INTO THE E ATLC E OF 26W.

$$
GR



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