Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 060605
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT MON JUL 06 2009

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0545 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 28W TO THE SOUTH OF 
16N MOVING WEST 15 TO 20 KT. MOST OF THE PRECIPITATION WITH THIS 
WAVE...IF NOT ALL OF IT...SOMEHOW IS WRAPPED UP IN THE ITCZ.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 66W/68W TO THE SOUTH OF 
20N MOVING WEST 20 TO 25 KT. THE WAVE IS MOVING THROUGH THE
AREA OF A PRE-EXISTING UPPER LEVEL TROUGH AND UPPER LEVEL 
ANTICYCLONIC FLOW IN THE SOUTHEASTERN CORNER OF THE AREA.
THE SHOWERS AND THUNDERSTORMS THAT COVER THE AREA FROM 17N
TO 21N BETWEEN 64W AND 71W...FROM THE DOMINICAN REPUBLIC TO 
PUERTO RICO AND SURROUNDING ISLANDS...ARE ON THE SOUTHERN
AND SOUTHEASTERN SIDE OF THE TROUGH AND ITS CYCLONIC FLOW.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 83W TO THE SOUTH OF 17N 
MOVING WEST 20 KT. THE SHOWERS AND THUNDERSTORMS IN THE 
SOUTHWESTERN CORNER OF THE AREA POSSIBLY ARE BEING HELPED BY
THE 83W TROPICAL WAVE AND THE UPPER LEVEL ANTICYCLONIC OUTFLOW.

...THE ITCZ...

FROM AFRICA NEAR 11N15W TO 10N27W TO 8N46W TO 9N56W...INTO
VENEZUELA NEAR 8N64W. ISOLATED MODERATE SHOWERS AND POSSIBLE
THUNDERSTORMS ARE WITHIN 180 NM ON EITHER SIDE OF 6N11W 7N24W
AND FROM 10N TO 14N BETWEEN AFRICA AND 25W...AND WITHIN 60 NM
TO 120 NM ON EITHER SIDE OF 11N28W 8N40W 7N50W 8N60W.

...DISCUSSION...

FROM THE ATLANTIC OCEAN TO THE WEST OF 70W
INTO THE GULF OF MEXICO AND INTERIOR MEXICO...
AN UPPER LEVEL TROUGH PASSES OVER ELEUTHERA ISLAND IN THE 
BAHAMAS INTO THE STRAITS OF FLORIDA...ACROSS THE YUCATAN
PENINSULA TO A CYCLONIC CIRCULATION CENTER NEAR 21N98W ALONG THE 
MEXICO COAST...TO A PERSISTENT CYCLONIC CENTER NEAR 25N105W IN 
INTERIOR MEXICO. DISSIPATING CONVECTIVE PRECIPITATION IS MOVING 
AWAY FROM THE PART OF MEXICO THAT IS IMMEDIATELY TO THE WEST OF 
THE YUCATAN PENINSULA JUST OFFSHORE. UPPER LEVEL NORTHEASTERLY 
TO EASTERLY WIND FLOW COVERS THE REST OF THE AREA. A MASS OF 
STRONG SHOWERS AND THUNDERSTORMS COVERS LOUISIANA TO THE NORTH 
OF 30N ALONG AN OUTFLOW BOUNDARY THAT IS TO THE EAST
OF AN ADVANCING COLD FRONT.

THE CARIBBEAN SEA...
AN UPPER LEVEL TROUGH PASSES THROUGH THE THE ATLANTIC OCEAN
FROM 30N64W TO 25N67W THROUGH THE WINDWARD PASSAGE INTO THE 
NORTHWESTERN CORNER OF THE AREA. THE SHOWERS AND THUNDERSTORMS 
THAT COVER THE AREA FROM 17N TO 21N BETWEEN 64W AND 71W...FROM 
THE DOMINICAN REPUBLIC TO PUERTO RICO AND SURROUNDING ISLANDS...
ARE ON THE SOUTHERN AND SOUTHEASTERN SIDE OF THE TROUGH AND ITS
CYCLONIC FLOW. A TROPICAL WAVE IS ALONG 66W/68W TO THE SOUTH OF 
20N. IT IS POSSIBLE THAT THIS WAVE IS ADDING SOME ENERGY AND 
ATMOSPHERIC INSTABILITY TO THE EASTERN CARIBBEAN SEA.
DISSIPATING BUT LINGERING CONVECTIVE PRECIPITATION IS JUST
TO THE WEST OF THE YUCATAN PENINSULA...AND IN THE GULF OF
TEHUANTEPEC ON THE EASTERN PACIFIC OCEAN COAST. SHOWERS AND
THUNDERSTORMS FROM SOUTHERN BELIZE/THE GULF OF HONDURAS INTO
HONDURAS AND EL SALVADOR ARE IN AN AREA THAT IS AT THE EDGE OF
THE TROUGH FROM THE ATLANTIC OCEAN INTO THE NORTHWESTERN CORNER
OF THE CARIBBEAN SEA AND SOME UPPER LEVEL DIFFLUENT FLOW. THE
SHOWERS AND THUNDERSTORMS IN THE SOUTHWESTERN CORNER OF THE AREA
POSSIBLY ARE BEING HELPED BY THE 83W TROPICAL WAVE AND THE UPPER
LEVEL ANTICYCLONIC OUTFLOW.

THE REST OF THE ATLANTIC OCEAN...
A CENTRAL ATLANTIC OCEAN DEEP LAYER TROUGH SUPPORTS A SURFACE 
TROUGH FROM A 1010 MB LOW PRESSURE CENTER NEAR 34N30W TO 30N31W 
TO A 1018 MB LOW PRESSURE CENTER NEAR 26N40W TO 23N44W. THE 
TROUGH ON WATER VAPOR SATELLITE IMAGERY EXTENDS FROM A CYCLONIC 
CIRCULATION CENTER NEAR 34N31W TO 28N35W TO 23N38W TO 12N55W. 
ISOLATED MODERATE SHOWERS ARE FROM 22N TO 27N BETWEEN 38W AND 
47W.

$$
MT