Tropical Weather Discussion
Issued by NWS

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000
AXNT20 KNHC 211756
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON JUL 21 2014

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURES...
TROPICAL WAVE EXTENDS FROM 11N42W TO 17N40W MOVING W AT 15-20
KT. A 1013 MB LOW IS CENTERED AT THE SOUTHERN EXTENT OF THE WAVE
NEAR 11N42W AND CONTINUES TO EXHIBIT A FAIRLY IMPRESSIVE
SATELLITE PRESENTATION WITH AN EARLIER ASCAT PASS AROUND 21/1210
UTC DEPICTING THE WESTERN HALF OF THE LOW-LEVEL WIND FIELD
SURROUNDING THE LOW. WIDELY SCATTERED MODERATE CONVECTION IS
FROM 09N-14N BETWEEN 41W-45W.

...TROPICAL WAVES...
TROPICAL WAVE EXTENDS FROM 11N32W TO 21N30W MOVING W AT 15 KT.
THE WAVE COINCIDES WITH A BROAD 700 MB TROUGH BETWEEN 28W-37W
WITH A 850 MB RELATIVELY VORTICITY MAXIMUM CENTERED ALONG THE
WAVE AXIS NEAR 16N. ISOLATED MODERATE CONVECTION IS FROM 12N-13N
BETWEEN 30W-33W.

TROPICAL WAVE EXTENDS FROM 11N73W TO 17N72W MOVING W AT 20 KT.
THE WAVE REMAINS EMBEDDED WITHIN A VERY BROAD 700 MB TROUGH
PROGRESSING ACROSS THE CARIBBEAN SEA WITH MODEL GUIDANCE
INDICATING MOST OF THE 850 MB RELATIVE VORTICITY LIES S OF 13N
BETWEEN 70W-80W. WIDELY SCATTERED MODERATE CONVECTION IS FROM
11N-17N BETWEEN 69W-75W.

TROPICAL WAVE EXTENDS FROM 09N86W TO 18N86W MOVING W AT 15 KT.
THE WAVE CONTINUES TO MOVE BENEATH UPPER LEVEL NORTHEASTERLY
FLOW WHICH IS MAINTAINING A FAIRLY STABLE ENVIRONMENT IN THE
VICINITY OF THE WAVE. HOWEVER...ISOLATED MODERATE CONVECTION IS
OCCURRING FROM 09N-13N BETWEEN 83W-86W AND IS LIKELY DUE TO LOW-
LEVEL MOISTURE CONVERGENCE ACROSS THE SW CARIBBEAN SEA.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N14W TO
08N20W TO 12N37W TO 11N42W. THE INTERTROPICAL CONVERGENCE ZONE
AXIS EXTENDS FROM 11N42W TO 09N44W TO 06N55W. ASIDE FROM
CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...WIDELY SCATTERED
MODERATE CONVECTION IS FROM 05N-10N BETWEEN 13W-33W.

...DISCUSSION...

GULF OF MEXICO...
A MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 31N87W THAT
SUPPORTS A STATIONARY FRONT EXTENDING ACROSS THE SE CONUS AND
ALONG THE LOUISIANA GULF COAST. A PRE-FRONTAL SURFACE TROUGH IS
ANALYZED FROM THE FAR WESTERN FLORIDA PANHANDLE SW TO 29N89W.
SCATTERED SHOWERS AND TSTMS ARE OCCURRING ACROSS THE NE GULF
WATERS N OF 27N BETWEEN 82W-89W. FARTHER SOUTH...NORTHEASTERLY
FLOW ALOFT PREVAILS S OF 26N WHICH IS PROVIDING OVERALL
STABILITY TO THE SOUTHERN GULF WATERS IN ADDITION TO A SURFACE
RIDGE WITH AXIS EXTENDING FROM THE SOUTHERN FLORIDA PENINSULA W-
SW TO A 1019 MB HIGH CENTERED ACROSS EAST-CENTRAL MEXICO NEAR
20N98W. THE RIDGE IS EXPECTED TO GRADUALLY LIFT NORTHWARD
THROUGH LATE TUESDAY AND ANCHOR ALONG 27N/28N THURSDAY AND
FRIDAY.

CARIBBEAN SEA...
UPPER LEVEL NORTH-NORTHEASTERLY FLOW IS OVER MUCH OF THE WESTERN
CARIBBEAN W OF AN UPPER LEVEL LOW CENTERED NEAR 17N74W WITH
TROUGH AXIS EXTENDING SOUTHWARD TO A BASE OVER THE SW CARIBBEAN
NEAR 11N79W. MOSTLY FAIR SKIES PREVAIL ACROSS THE WESTERN
CARIBBEAN WITH THE EXCEPTION OF A FEW ISOLATED SHOWERS AND TSTMS
OCCURRING ACROSS INLAND PORTIONS OF NICARAGUA...COSTA RICA...AND
PANAMA...AND A FEW ISOLATED SHOWERS AND TSTMS OCCURRING N OF 18N
BETWEEN 75W-84W. OTHERWISE...THE ONLY OTHER SIGNIFICANT FEATURE
ACROSS THE CARIBBEAN IS THE PRESENCE OF A TROPICAL WAVE ALONG
73W GENERATING WIDELY SCATTERED SHOWERS AND TSTMS FROM 11N-17N
BETWEEN 69W-75W. MODERATE TO FRESH TRADE CONTINUE AND ARE
EXPECTED TO PERSIST THROUGH MUCH OF THE WEEK AHEAD...
OCCASIONALLY WITH STRONGER WINDS 25 TO 30 KT OCCURRING WITHIN
CLOSE PROXIMITY TO THE COAST OF COLOMBIA AND NW VENEZUELA.

...HISPANIOLA...
CURRENTLY THE ISLAND IS UNDER CLEAR SKIES...HOWEVER AS THE
AFTERNOON PROGRESSES AND PEAK HEATING AND INSTABILITY ARE
REACHED...ISOLATED SHOWERS AND TSTMS ARE EXPECTED ACROSS THE
ISLAND INTO THE EVENING HOURS. THE CONVECTION IS LIKELY TO BE
ENHANCED DUE TO AN UPPER LEVEL LOW NOTED ON WATER VAPOR IMAGERY
NEAR 17N74W.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL TROUGH IS OVER THE SE CONUS CENTERED
OVER ALABAMA NEAR 31N87W SUPPORTING A SURFACE FRONT TO THE NORTH
OF THE DISCUSSION AREA ALONG 35N. TO THE SOUTH OF THE
BOUNDARY...SOUTHERLY FLOW ACROSS THE SW NORTH ATLC IS PROVIDING
FOR LOW-LEVEL MOISTURE CONVERGENCE AND GENERATING SCATTERED
SHOWERS AND TSTMS FROM 22N-32N BETWEEN 74W-80W. FARTHER EAST...
AN ELONGATED UPPER LEVEL LOW IS CENTERED NEAR 26N64W THAT
SUPPORTS A SURFACE TROUGH ANALYZED FROM 25N60W TO 33N58W. THE
REMAINDER OF THE CENTRAL AND EASTERN ATLC ARE UNDER THE
INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1027 MB HIGH CENTERED
NEAR 34N33W AND A 1026 MB HIGH CENTERED NEAR 33N41W.

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

$$
HUFFMAN



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