[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 140538
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU JUL 14 2011

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0500 UTC.

...TROPICAL WAVES...

TROPICAL WAVE APPEARS TO HAVE MOVED OFF THE W COAST OF AFRICA
AND WILL BE ADDED TO THE NEXT ANALYSIS.

TROPICAL WAVE IN THE CENTRAL TRPCL ATLC IS ALONG 16N31W TO 7N37W
MOVING W 15 KT. RECENT DATA FROM TOTAL PRECIPITABLE WATER
IMAGERY SHOWS A SURGE OF MOISTURE SLIGHTLY W OF THE CURRENT WAVE
LOCATION NEAR 40W. THIS INDICATES THAT THE WAVE AXIS IS PROBABLY
IN THAT VICINITY. SINCE DURING THE LIFE OF THIS WAVE ITS SURFACE
REPRESENTATION HAS BEEN WEAK...IT IS LIKELY THAT THE WAVE
ANALYSIS DEPICTED A WWD PROPAGATION THAT WAS SLOWER THAN THE
ACTUAL WAVE. BASED ON THIS...THE WAVE WILL BE RELOCATED ON THE
NEXT ANALYSIS. NO DEEP CONVECTION IS ASSOCIATED WITH THE WAVE.

TROPICAL WAVE IN THE ERN CARIBBEAN EXTENDS ACROSS ERN DOMINICAN
REPUBLIC FROM 21N69W TO 11N71W MOVING W 15-20 KT. WAVE CONTINUES
TO PRECEDE A SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL
PRECIPITABLE WATER IMAGERY. HOWEVER...AN AREA OF MOISTURE IS
ALSO AHEAD OF IT ACROSS THE NRN CARIBBEAN. THIS AREA OF MOISTURE
IS NOT PREVIOUSLY ASSOCIATED WITH THE WAVE...BUT WILL LIKELY
ENHANCE CONVECTION NEAR THE WAVE. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS OVER PUERTO RICO FROM 16N-19N BETWEEN
65W-67W...AND ACROSS HAITI FROM 18N-20N BETWEEN 72W-75W.
ISOLATED MODERATE CONVECTION IS FROM 17N-20N BETWEEN 58W-64W.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN
AT 22N ALONG 18N11W 11N20W 10N30W. THE ITCZ CONTINUES FROM
10N30W ALONG 7N44W 6N57W. A CLUSTER OF STRONG CONVECTION IS FROM
12N-14N BETWEEN 19W-20W. SCATTERED MODERATE/ISOLATED STRONG
CONVECTION IS FROM 6N-12N BETWEEN 13W-17W...AND WITHIN 100 NM OF
THE AXIS BETWEEN 37W-51W.

...DISCUSSION...

GULF OF MEXICO...
A TROPICAL WAVE PREVIOUSLY IN THE BAY OF CAMPECHE HAS NOW
DISSIPATED OVER MEXICO. HOWEVER...A SURFACE CIRCULATION STILL
REMAINS INLAND AROUND A 1006 MB LOW NEAR 19N98W SUPPORTING
SCATTERED SHOWERS/THUNDERSTORMS ACROSS SRN MEXICO. A CLUSTER OF
STRONG SHOWERS/THUNDERSTORMS IS ALSO IN THE BAY OF CAMPECHE FROM
18N-21N BETWEEN 92W-94W. WEAK SURFACE RIDGING ALONG 26N COVERS
THE REMAINDER OF THE GULF OF MEXICO AROUND A 1015 MB HIGH NEAR
26N88W SUPPORTING FAIR WEATHER AND LIGHT ANTI-CYCLONIC FLOW
AROUND THE RIDGE. A FEW ISOLATED SHOWERS...REMNANTS OF AFTERNOON
CONVECTION...ARE ACROSS THE NE GULF N OF 26N BETWEEN 83W-90W.
ALOFT...MAINLY NELY FLOW COVERS THE BASIN BETWEEN AN UPPER LEVEL
RIDGE CENTERED OVER NRN TEXAS AND AN UPPER LEVEL LOW OVER THE NW
CARIBBEAN. A WEAK UPPER RIDGE IS ALSO OVER NE MEXICO NEAR 23N96W
WITH CIRCULATION COVERING THE BAY OF CAMPECHE. WATER VAPOR
IMAGERY INDICATES DRY AIR IS BEING DRAWN IN THE NELY FLOW ALOFT
FROM THE W ATLC WHICH IS FURTHER SUPPORTING THE FAIR WEATHER.
TOTAL PRECIPITABLE WATER IMAGERY STILL INDICATES ENHANCED
MOISTURE IS ACROSS THE NRN GULF. WITH DAYTIME HEATING THIS WILL
LIKELY MEAN SHOWERS/THUNDERSTORMS WILL POP UP LATER IN THE
AFTERNOON TODAY. WEAK SURFACE RIDGING WILL CONTINUE OVER THE NRN
GULF.

CARIBBEAN SEA...
THE NW CARIBBEAN IS CURRENTLY UNDER FAIR CONDITIONS AS DRY AIR
ALOFT IS BEING WRAPPED AROUND AN UPPER LEVEL LOW NEAR 20N82W.
SOME MOISTURE IS BEING DRAWN AROUND THE ERN SIDE OF THE UPPER
LOW WHICH IS SUPPORTING A FEW ISOLATED SHOWERS 15N-23N BETWEEN
77W-82W. THE SW CARIBBEAN REMAINS UNDER MOIST CONDITIONS
INFLUENCED BY THE MONSOON TROUGH THAT EXTENDS FROM THE E PACIFIC
JUST S OF MEXICO...ACROSS GUATEMALA...THE EL SALVADOR/HONDURAS
BORDER...AND ACROSS NICARAGUA TO NRN COLOMBIA. LARGE CLUSTERS OF
STRONG SHOWERS/THUNDERSTORMS ARE CURRENTLY ACROSS VENEZUELA FROM
6N-9N BETWEEN 64W-68W...ACROSS NRN COLOMBIA FROM 6N-11N BETWEEN
71W-76W...AND N OF PANAMA FROM 9N-11N BETWEEN 79W-82W. SCATTERED
SHOWERS/THUNDERSTORMS COVERS THE REMAINDER OF THE AREA S OF 15N
BETWEEN 73W-83W. TOTAL PRECIPITABLE WATER IMAGERY INDICATES AN
AREA OF ENHANCED MOISTURE THAT WAS OVER THE NE CARIBBEAN A DAY
OR SO AGO HAS NOW SHIFTED W ACROSS THE N CENTRAL CARIBBEAN AHEAD
OF A TROPICAL WAVE ALONG 70W. ENHANCED MOISTURE ALSO TRAILS THE
WAVE ACROSS THE ERN CARIBBEAN. SEE TROPICAL WAVE SECTION FOR
MORE DETAILS. SIGNIFICANT RAINFALL HAS ALREADY FALLEN ACROSS
SOME OF THESE N CENTRAL CARIBBEAN ISLANDS WITH THE FIRST BATCH
OF MOISTURE...ESPECIALLY THE DOMINICAN REPUBLIC WHICH HAS
REPORTED OVER 7 INCHES IN SOME AREAS OF THE LAST 24 HOURS. WITH
THE WAVE APPROACHING...HEAVY RAINFALL COULD CONTINUE OVER THE
NEXT DAY OR SO INCREASING THE CHANCE FOR LOCALIZED FLOODING AND
MUDSLIDES. CURRENTLY...SCATTERED SHOWERS/THUNDERSTORMS ARE W OF
HAITI FROM 18N-20N BETWEEN 72W-75W...AND ACROSS PUERTO RICO AND
THE VIRGIN ISLANDS FROM 16N-20N E OF 67W. ALOFT...UPPER LEVEL
TROUGHING COVERS THE ERN CARIBBEAN EXTENDING FROM THE CENTRAL
ATLC ALONG 23N52W TO 13N64W. EXPECT SHOWER/THUNDERSTORM ACTIVITY
TO CONTINUE ACROSS MUCH OF THE NRN CARIBBEAN AND ERN CARIBBEAN
AS THE AREAS OF MOISTURE BOTH AHEAD AND BEHIND THE WAVE AXIS
MOVE WWD. ALSO...MUCH OF CENTRAL AMERICA AND SRN MEXICO HAS
ALREADY RECEIVED LARGE AMOUNTS OF RAINFALL OVER THE PAST COUPLE
OF DAYS WHICH COULD CONTINUE THROUGH THE END OF THE WEEK WHICH
WILL INCREASE THE CHANCE FOR DEADLY FLOODING AND MUDSLIDES.
MODEL GUIDANCE INDICATES THE MONSOON TROUGH WILL CONTINUE TO
LIFT FARTHER N WITH POSSIBLE LOW LEVEL CIRCULATIONS FORMING
ALONG THE AXIS. THE W-SW FLOW ASSOCIATED WITH THE MONSOON TROUGH
WILL DRAW SIGNIFICANT TROPICAL MOISTURE ACROSS THESE AREAS.
COMBINED WITH OROGRAPHIC LIFT DUE TO MOUNTAINS THIS CREATES A
FORMULA TO EQUAL HEAVY PRECIPITATION. THESE AREAS SHOULD MONITOR
THE SITUATION OVER THE NEXT FEW DAYS AND STAY TUNED FOR UPDATES
ON THIS SCENARIO.

ATLANTIC OCEAN...
SURFACE RIDGING DOMINATES THE MAJORITY OF THE ATLC ANCHORED BY A
1033 MB AZORES HIGH NEAR 40N27W PROVIDING MOSTLY FAIR CONDITIONS
BASIN-WIDE. ALOFT...AN UPPER LEVEL RIDGE COVERS THE WRN ATLC
CENTERED OVER TEXAS. AN UPPER LEVEL TROUGH IS TO THE E
ALONG 52W. A SHORTWAVE UPPER TROUGH EXTENDS OFF THE MAIN TROUGH
EXTENDING TO THE ERN CARIBBEAN. THIS IS PRODUCING SOME UPPER
LEVEL CLOUDS AND ISOLATED SHOWERS FROM N OF 24N BETWEEN 51W-65W.
UPPER LEVEL RIDGING COVERS THE ERN ATLC CENTERED NEAR 37N37W. AN
UPPER LEVEL TROUGH COVERS THE FAR ERN ATLC EXTENDING FROM SPAIN
TO THE CANARY ISLANDS. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL
RIDGE IS CENTERED OFF THE W COAST OF AFRICA NEAR 19N23W.

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

$$
WALTON





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