Home


000
AXNT20 KNHC 210557
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU AUG 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC.


...SPECIAL FEATURES...

AN ELONGATED 1009 MB ATLANTIC OCEAN LOW PRESSURE CENTER IS LOCATED NEAR 12N54W...IN THE MONSOON TROUGH. A TROPICAL WAVE IS ALSO ATTACHED TO THIS LOW. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 10N-15N BETWEEN 52W-58W. GRADUAL DEVELOPMENT OF THIS FEATURE IS POSSIBLE DURING THE NEXT FEW DAYS...WHILE MOVING WNW AT 10-15 KNOTS...ACROSS THE LESSER ANTILLES INTO THE CARIBBEAN SEA. INTERESTS IN THE LESSER ANTILLES AND THE ISLANDS OF THE NORTHEASTERN CARIBBEAN SEA SHOULD MONITOR CLOSELY THE PROGRESS OF THIS SYSTEM. THE CHANCE FOR DEVELOPMENT INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS IS MEDIUM.


...TROPICAL WAVES...

A TROPICAL WAVE AXIS EXTENDS FROM 23N22W TO 13N25W MOVING W AT 10 KT. THIS WAVE COINCIDES WITH 700 MB TROUGHING ALOFT AND SSMI TOTAL PRECIPITABLE WATER MAXIMUM. SCATTERED SHOWERS AND THUNDERSTORMS ARE WITHIN 90 NM EAST OF THE WAVE AXIS.

A TROPICAL WAVE AXIS EXTENDS FROM 23N53W TO 13N54W MOVING W AT 20-25 KT. THIS WAVE IS EMBEDDED WITH THE SPECIAL FEATURE LOW DESCRIBED ABOVE. THIS WAVE COINCIDES WITH 700 MB TROUGHING ALOFT. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOWS VERY MOIST ENVIRONMENT SURROUNDING THIS WAVE...WITH MOISTURE MAXIMA S OF 20N.


...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N17W TO 9N38W TO 13N52W TO 1009 MB LOW AT 12N54W TO THE COAST OF SOUTH AMERICA NEAR 9N60W. BESIDES THE CONVECTION MENTIONED IN THE SPECIAL FEATURES SECTION AND THE TROPICAL WAVE SECTION... ISOLATED MODERATE CONVECTION IS PRESENT FROM 9N-13N BETWEEN 35W- 40W.


...DISCUSSION...

GULF OF MEXICO...

A QUASI-STATIONARY 1019 MB HIGH IS CENTERED OVER THE NE GULF OF MEXICO NEAR 28N88W. 5-10 KT ANTICYCLONIC WINDS ARE OVER THE EASTERN GULF AND 10-15 KT WINDS PREVAIL OVER THE REMAINING WATERS EAST OF 90W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE LOCATED ACROSS THE FLORIDA STRAITS MAINLY E OF 83W. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED NORTH OF TAMPICO MEXICO AT 23N98W. AN UPPER LEVEL HIGH IS CENTERED OVER THE E GULF NEAR 26N84W. UPPER LEVEL DIFFLUENCE W OF THIS HIGH CENTER IS PRODUCING ISOLATED MODERATE CONVECTION OVER THE NNW GULF FROM 26N-28N BETWEEN 93W-96W. EXPECT OVER THE NEXT 24 HOURS FOR MORE SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE SW GULF.

CARIBBEAN SEA...

10-20 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. MOSTLY FAIR WEATHER IS PREVAILING OVER THE CENTRAL CARIBBEAN. SCATTERED MODERATE CONVECTION IS ACROSS THE WEST COAST OF CUBA...MOVING QUICKLY OFFSHORE. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE LOCATED SOUTH OF CENTRAL CUBA AND NORTHEAST OF JAMAICA. SCATTERED MODERATE CONVECTION IS OVER THE PANAMA COAST...E OF COSTA RICA FROM 10N-12N BETWEEN 79W-82W. IN THE UPPER LEVELS...THE MAJORITY OF THE CARIBBEAN IS UNDER THE INFLUENCE OF DRY UPPER LEVEL CYCLONIC CIRCULATIONS ALOFT...ONE CENTERED OVER THE W CARIBBEAN NEAR 18N82W AND THE OTHER CENTERED OVER N HISPANIOLA NEAR 20N70W THAT EXTENDS UPPER LEVEL TROUGHING OVER MUCH OF THE EASTERN CARIBBEAN E OF 74W. STRONG SUBSIDENCE IS OVER THE NW CARIBBEAN. EXPECT OVER THE NEXT 24 HOURS FOR ADDITIONAL CONVECTION TO BE OVER THE E CARIBBEAN DUE TO AN APPROACHING LOW AND TROPICAL WAVE. ALSO EXPECT CONTINUED CONVECTION OVER THE SW CARIBBEAN AND SOUTHERN CENTRAL AMERICA.


...HISPANIOLA...

EVENING CONVECTION IS OVER E HISPANIOLA DUE TO DAYTIME HEATING AND INSTABILITY. EXPECT SIMILAR CONVECTION THU AFTERNOON AND EVENING.

ATLANTIC OCEAN...

A 1025 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 32N45W WITH SURFACE RIDGING EXTENDING TO THE EASTERN GULF OF MEXICO. ISOLATED SHOWERS AND THUNDERSTORMS ARE W OF THE BAHAMAS ALONG 25N BETWEEN 78W-79W. ANOTHER 1024 MB HIGH IS OVER THE E ATLANTIC NEAR 36N22W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS NEAR 30N51W. AN UPPER LEVEL LOW IS CENTERED OVER THE W ATLANTIC NEAR 24N67W. EXPECT OVER THE NEXT 24 HOURS FOR ADDITIONAL SHOWERS MAINLY E OF THE LESSER ANTILLES S OF 20N BETWEEN 50W-60W.

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

$$ RIVERA/HUFFMAN

Home