[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 240535
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU JUL 23 2015

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.

...TROPICAL WAVES...

TROPICAL WAVE IN THE TROPICAL ATLC EXTENDS ALONG 37W FROM 9N-17N
MOVING W 10-15 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE
WATER IMAGERY SHOWS THE WAVE IS N OF ANY DEEP MOISTURE. THE
NOAA/NESDIS AEROSOL PRODUCT AND THE LAST VISIBLE SATELLITE
IMAGERY INDICATES THAT THE WAVE REMAINS EMBEDDED WITHIN A PLUMB
OF AEROSOLS OR SAHARAN DUST LIMITING ANY ASSOCIATED CONVECTION.

TROPICAL WAVE IN THE CENTRAL CARIBBEAN EXTENDS ALONG 77W/78W S
OF 18N TO ACROSS PANAMA MOVING W 20-25 KT OVER THE PAST 24
HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS
EMBEDDED WITHIN A BROAD AREA OF MODERATE TO DEEP MOISTURE THAT
COVERS THE CARIBBEAN W OF 70W. NO ASSOCIATED DEEP CONVECTION BUT
IS ENHANCING THE ACTIVITY ASSOCIATED WITH THE UPPER LOW.

TROPICAL WAVE IN THE W CARIBBEAN EXTENDS ALONG 88W S OF 17N TO
ACROSS CENTRAL AMERICA MOVING W-SW NEAR 15-20 KT OVER THE PAST
24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS
EMBEDDED WITHIN A BROAD AREA OF MODERATE TO DEEP MOISTURE THAT
COVERS THE CARIBBEAN W OF 70W. NO ASSOCIATED DEEP CONVECTION.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E
TROPICAL ATLC NEAR 13N17W ALONG 10N23W TO 8N35W WHERE THE ITCZ
BEGINS AND CONTINUES ALONG 8N43W TO SOUTH AMERICA NEAR 6N55W.
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE
WITHIN 250 NM S OF THE MONSOON TROUGH E OF 26W TO THE COAST OF
AFRICA AND WITHIN 150 NM N OF THE ITCZ 45W-50W. CLUSTERS OF
SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM S OF THE MONSOON
TROUGH/ITCZ BETWEEN 27W-43W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE IS ANCHORED OVER THE FLORIDA PANHANDLE COVERING
THE E GULF WHILE THE UPPER LOW CENTERED IN THE SW GULF NEAR
24N93W COVERS THE REMAINDER OF THE GULF. THE UPPER RIDGE IS
PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED TO NUMEROUS
SHOWERS WITH ISOLATED THUNDERSTORMS ACROSS THE NE GULF N OF 28N
E OF 87W. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC THROUGH
THE STRAITS OF FLORIDA TO NE TEXAS WITH A 1018 MB HIGH NEAR
26N87W. ISOLATED SHOWERS ARE POSSIBLE ACROSS THE FAR E GULF S OF
28N E OF 85W LEAVING THE REMAINDER OF THE GULF WITH CLEAR SKIES
TONIGHT. SURFACE RIDGE WILL PERSIST THROUGH SUN. A TROUGH OF LOW
PRESSURE MAY ENTER THE NE GULF SUN NIGHT.

CARIBBEAN SEA...
AN UPPER LOW IS CENTERED JUST S OF HAITI NEAR 17N75W WITH AN
UPPER TROUGH COVERING THE CARIBBEAN BETWEEN 69W-85W. THIS UPPER
TROUGH COUPLED WITH THE TROPICAL WAVE IS GENERATING SCATTERED TO
NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS FROM 18N TO OVER HAITI
AND E CUBA BETWEEN 72W-77W AND ISOLATED SHOWERS/THUNDERSTORMS
DOTTING THE REMAINDER OF THE AREA N OF 18N BETWEEN 77W-86W. AN
UPPER RIDGE ANCHORED IN THE TROPICAL ATLC EXTENDS ACROSS THE E
CARIBBEAN. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE
SW CARIBBEAN S OF 13N W OF 73W TO OVER CENTRAL AMERICA LEAVING
THE REMAINDER OF THE CARIBBEAN WITH MOSTLY CLEAR SKIES TONIGHT.
W ATLC SURFACE RIDGE WILL MAINTAIN MODERATE TO FRESH TRADE WINDS
WITH STRONG TO OCCASIONAL NEAR GALE CONDITIONS OCCURRING OFF THE
COAST OF COLOMBIA AND VENEZUELA THROUGH SUN. THE W CARIBBEAN
TROPICAL WAVE WILL MOVE OUT THE BASIN OVERNIGHT. THE CENTRAL
CARIBBEAN TROPICAL WAVE WILL INTO THE W CARIBBEAN THROUGH SAT. A
THIRD TROPICAL WAVE WILL ENTER THE E CARIBBEAN SUN.

...HISPANIOLA...
SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS ARE OVER
HAITI AND THE GULF OF GONAVE MOVING WESTWARD. THIS ACTIVITY IS
DUE TO THE UPPER LOW S OF HAITI AND THE TROPICAL WAVE MOVING
AWAY FROM THE ISLAND. THIS UPPER LOW WILL MOVE W GIVING THE
ISLAND SOUTHERLY FLOW ALOFT FRI AND SAT WITH AN UPPER RIDGE
SETTING UP ON SUN. MOISTURE ASSOCIATED WITH THE TROPICAL WAVE
WILL LINGER THROUGH FRI INCREASING THE CHANCES OF AFTERNOON
SHOWERS/THUNDERSTORMS. SAT AND SUN WILL SEE A SLIGHT BREAK IN
THE MOISTURE AND WITH DAYTIME HEATING COULD STILL PRODUCE A
CHANCE OF SHOWERS AND POSSIBLE THUNDERSTORMS DURING THE
AFTERNOON/EVENINGS HOURS.

ATLANTIC OCEAN...
AN E/W ELONGATED UPPER RIDGE IS ANCHORED IN THE W ATLC NEAR
30N68W COVERING THE W ATLC N OF 24N W OF 60W. THE UPPER LOW
CENTERED S OF HAITI COVERS THE W ATLC S OF 24N AND IS
GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 23N TO
OVER CUBA BETWEEN 74W-76W. AN NE/SW ELONGATED UPPER LOW IS
CENTERED IN THE CENTRAL ATLC NEAR 26N50W SUPPORTING A SURFACE
TROUGH THAT EXTENDS FROM 28N47W TO 30N50W AND GENERATING
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 180 NM EITHER
SIDE OF THE TROUGH AND FROM 27N-31N BETWEEN 54W-59W. THE ATLC
BASIN IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH
N OF THE DISCUSSION AREA NEAR 33N35W AND EXTENDING A RIDGE AXIS
THROUGH A 1023 MB HIGH NEAR 27N55W THEN W THROUGH THE STRAITS OF
FLORIDA AND INTO THE GULF OF MEXICO. SURFACE RIDGE WILL RETREAT
EASTWARD AND WEAKEN FRI NIGHT AND SAT AS A WEAK LOW MOVES OFF
THE SE U.S. COAST.  THE LOW WILL THEN MOVE N OF THE AREA SUN
NIGHT.

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

$$
PAW
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