[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 061101
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT JUN 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1045 UTC.

...TROPICAL WAVES...

A WEAK TROPICAL WAVE IS ALONG 42W TO THE SOUTH OF 10N AT
06/0600 UTC. THE WAVE IS MOVING WESTWARD 15 KT. NO SIGNIFICANT
DEEP CONVECTIVE PRECIPITATION IS ASSOCIATED WITH IT AND IT IS
QUITE DIFFICULT TO TRACK THE MOVEMENT OF THIS WAVE AS NEITHER
THE GFS MODEL NOR THE ECMWF MODEL SHOWS THE WAVE. THE ONLY HINT
THAT THE WAVE STILL IS VIABLE IS A SLIGHT MAXIMA IN THE TOTAL
PRECIPITABLE WATER IMAGERY NEAR THE WAVE.

A TROPICAL WAVE IS ALONG 16N56W 12N58W TO 8N58W AT 06/0600 UTC.
THE NORTHERN PART OF THE WAVE THAT EXISTED AT 16/0000 UTC HAS
BROKEN AWAY IN THE FORM OF A SURFACE TROUGH THAT IS ALONG 22N57W
20N58W 17N59W. A SECOND SURFACE TROUGH LAGS BEHIND ALONG 22N49W
19N50W. ISOLATED MODERATE SHOWERS ARE AROUND THE PERIPHERY OF
THE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW THAT IS AROUND THE
25N57W CYCLONIC CIRCULATION CENTER ON WATER VAPOR IMAGERY.
THAT PRECIPITATION MAY BE MORE RELATED TO THE BROAD CYCLONIC
FLOW INSTEAD OF THE WAVE AND TROUGHS.

...THE ITCZ...

FROM AFRICA NEAR 11N14W TO 7N20W 2N30W...CROSSING THE EQUATOR
ALONG 35W...INTO NORTHEASTERN BRAZIL NEAR 2S48W. UPPER LEVEL
DIFFLUENT WIND FLOW MAY BE A FACTOR IN THE STRONG SHOWERS AND
THUNDERSTORMS FROM 6N TO 8N BETWEEN 52W AND 57W...AND NOT THE
ITCZ. SCATTERED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS
ARE FROM 3S TO 3N BETWEEN 37W AND 50W. STRONG CONVECTIVE
PRECIPITATION WITHIN A 30 NM RADIUS OF 10N16W HAS BEEN WEAKENING
WITH TIME DURING THE LAST SIX HOURS. ISOLATED MODERATE SHOWERS
ARE FROM 1N TO 7N TO THE EAST OF 40W.

...DISCUSSION...

THE GULF OF MEXICO...
A DEEP LAYER TROUGH IS MOVING THROUGH THE EASTERN PART OF THE
AREA...EXTENDING FROM THE CAROLINAS TO FLORIDA. CYCLONIC FLOW
ON WATER VAPOR IMAGERY COVERS THE AREA TO THE EAST OF 90W.
A DISSIPATING COLD FRONT PASSES THROUGH NORTH CENTRAL FLORIDA
TO 26N85W TO 22N91W. A THIN AREA OF HIGH PRESSURE PASSES THROUGH
THE LOUISIANA/TEXAS BORDER INTO THE SOUTHWESTERN CORNER OF THE
AREA. SHOWERS ARE POSSIBLE TO THE NORTHWEST OF THE LINE FROM
BELIZE TO THE CAYMAN ISLANDS...MOVING ONSHORE ALONG THE WESTERN
FLORIDA COAST TO THE WEST OF LAKE OKEECHOBEE...AND IN THE
ATLANTIC OCEAN TO THE NORTH OF 23N TO THE WEST OF 70W.

THE CARIBBEAN SEA...
CYCLONIC FLOW IS REACHING THE NORTHWESTERN CORNER OF THE AREA
THANKS TO THE EASTERN GULF OF MEXICO TROUGH THAT IS SUPPORTING
THE DISSIPATING COLD FRONT. SHOWERS AND THUNDERSTORMS HAVE BEEN
OCCURRING IN COASTAL AREAS OF THE EASTERN PACIFIC OCEAN IN
CENTRAL AMERICA FROM PANAMA TO COSTA RICA TO THE AREA NEAR
NICARAGUA/HONDURAS/EL SALVADOR...IN THE PRESENCE OF A TROPICAL
WAVE AND THE ITCZ AND BROAD SURFACE LOW PRESSURE. THAT
PRECIPITATION HAS BEEN MOVING MORE AND MORE OFFSHORE WITH TIME.
STRONG SHOWERS AND THUNDERSTORMS ARE FROM 12N TO 13N BETWEEN
77W AND 79W...UNDER UPPER LEVEL ANTICYCLONIC OUTFLOW. UPPER
LEVEL ANTICYCLONIC FLOW COVERS THE REST OF THE AREA.
THE SURFACE PRESSURE GRADIENT IS WEAK.

THE ATLANTIC OCEAN...
THE PRECIPITATION IN THE ATLANTIC OCEAN TO THE NORTH OF 20N TO
THE WEST OF 70W IS ASSOCIATED WITH THE DEEP LAYER TROUGH AND
DISSIPATING COLD FRONT IN THE EASTERN GULF OF MEXICO. A MIDDLE
LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 25N57W.
BROAD CYCLONIC FLOW ON WATER VAPOR IMAGERY COVERS THE AREA TO
THE NORTH OF 18N BETWEEN 50W AND 70W. SHOWERS ARE POSSIBLE FROM
18N TO 32N BETWEEN 50W AND 60W.

$$
MT





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