AXNT20 KNHC 041747
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT MON 04 AUG 2003

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...AND ATLANTIC OCEAN
TO THE AFRICAN COAST FROM THE EQUATOR TO 32N INCLUDING NORTHERN 
SECTIONS OF SOUTH AMERICA. 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...
NONE.
  
TROPICAL WAVES/ITCZ...
TROPICAL WAVE ALONG 21W SOUTH OF 19N MOVING WEST 10-15 KT.
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN
45-60 NM RADIUS OF 9.5N25W JUST WEST OF THE WAVE.

TROPICAL WAVE ALONG 36W/37W SOUTH OF 19N MOVING WEST 10-15 KT.
NO DEEP CONVECTIVE ACTIVITY.

TROPICAL WAVE ALONG 54W SOUTH OF 19N MOVING WEST 5-10 KT.
1013 MB LOW PRESSURE CENTER ALONG WAVE NEAR 15.5N. THIS
WAVE/LOW CENTER MIGHT NOT REACH THE EASTERN CARIBBEAN
ISLANDS UNTIL 36 HOURS FROM NOW...BASED ON ITS MOVEMENT
DURING THE LAST 24 HOURS. WARMING CLOUD TOP TEMPERATURES AND 
DISSIPATING CONVECTIVE ACTIVITY FROM 15N TO 19N BETWEEN 52W
AND 58W. SCATTERED STRONG CONVECTION WAS WITHIN 30-40 NM
RADIUS OF 16.5N55W FIVE HOURS AGO.

TROPICAL WAVE ALONG 72W SOUTH OF 16N MOVING WEST 10-15 KT.
LOW CLOUDS RACING WESTWARD IN LOW LEVEL EASTERLY WIND FLOW ON 
VISIBLE SATELLITE IMAGERY. SCATTERED STRONG THUNDERSTORM CELLS 
FROM 10N TO 12N BETWEEN 76W AND 78W PROBABLY NOT WITH THIS WAVE. 
THIN LINE OF CONVECTIVE CELLS WITHIN 15 NM ON EITHER SIDE OF 14N 
BETWEEN 77W AND 79W MIGHT BE RELATED TO SOME TYPE OF LOW LEVEL 
CONFLUENT FLOW. HIGH CLOUD BUILDUPS FROM 17N TO SW HAITI COAST 
BETWEEN 73W AND 76W.

TROPICAL WAVE ALONG 89W/90W SOUTH OF 24N MOVING WEST 10-15 KT. 
NO DEEP CONVECTION IN ATLANTIC BASIN.

AXIS OF ITCZ-RELATED CLOUDS/CONVECTION 10N10W 9N25W 8N40W 7N60W.
ISOLATED MODERATE TO LOCALLY STRONG SHOWERS AND THUNDERSTORMS
WITHIN 180-240 NM ON EITHER SIDE OF AXIS EAST OF 20W...AND WITHIN
180 NM ON EITHER SIDE OF AXIS BETWEEN 30W AND 50W.

MIDDLE/UPPER LEVEL SYNOPTIC FEATURES...
WESTERN CENTRAL GULF OF MEXICO CYCLONIC CIRCULATION CENTER NEAR
25N94W. CYCLONIC FLOW COVERS MOST OF GULF OF MEXICO WEST OF 90W.
BROAD ANTICYCLONIC FLOW IN REST OF GULF OF MEXICO...EAST OF 90W.
THE COMPARATIVELY SHARPER AND MUCH MORE WELL-DEFINED RIDGE WHICH
WAS IN THE EASTERN GULF OF MEXICO TWENTY FOUR HOURS AGO DOES NOT
APPEAR AT THIS TIME.

WESTERN CARIBBEAN SEA...OVER CENTRAL AMERICA...RIDGE IS
COMPARATIVELY MORE WELL DEFINED...BETWEEN 85W AND 93W. BROAD
UPPER LEVEL ANTICYCLONIC FLOW ORIGINATING OVER SOUTH AMERICA 
REACHES AS FAR NORTH AS 16N BETWEEN 68W AND 75W. BROAD CYCLONIC 
FLOW COVERS MUCH OF REST OF CARIBBEAN SEA WEST OF 70W. BROAD 
AREA OF WEAK CYCLONIC FLOW IN SE CORNER OF CARIBBEAN SEA...
SOUTH OF 14N EAST OF 66W.

ATLANTIC OCEAN...HIGH LEVEL ANTICYCLONIC FLOW ON TOP OF MIDDLE
TO UPPER LEVEL DRY AIR NORTH OF 20N WEST OF 60W...DRY AIR ALSO
IN CARIBBEAN SEA EAST OF 70W. CYCLONIC CIRCULATION CENTER NEAR
24N45W...HAS BEEN AROUND FOR AT LEAST THE LAST THREE DAYS...WITH 
NO SURFACE LOW CENTER. MIDDLE TO UPPER LEVEL CYCLONIC FLOW WITHIN
300 NM RADIUS OF 24N45W CENTER. MIDDLE TO UPPER LEVEL WESTERLY 
FLOW RACING ACROSS ATLANTIC WATERS NORTH OF 30N EAST OF 40W. 
BROAD ANTICYCLONIC FLOW...IN MIDDLE TO UPPER LEVEL DRY AIR... 
FROM 20N TO 30N EAST OF 35W. BROAD MIDDLE TO UPPER LEVEL 
CYCLONIC FLOW WITHIN 400 NM WEST OF 36W/37W TROPICAL WAVE...
AND WITHIN 500 NM WEST OF 21W TROPICAL WAVE.

SURFACE SYNOPTIC FEATURES...
COLD FRONT THROUGH 30N44W TO 28N50W TO 26N60W. BROKEN TO
OVERCAST MULTILAYERED CLOUDS AND ISOLATED TO WIDELY SCATTERED
MODERATE/LOCALLY STRONG SHOWERS AND THUNDERSTORMS WITHIN
200 NM NORTHWEST OF THE LINE 24N57W 26N50W 30N43W BEYOND 32N38W.
 
RIDGE WITHIN 300-350 NM ON EITHER SIDE OF LINE THROUGH BERMUDA
TO 27N73W TO EASTERN CUBA...AND WITHIN 250 NM ON EITHER SIDE OF 
LINE FROM EASTERN CUBA TO 19N81W TO 9N83W. ANOTHER RIDGE WITHIN
150 NM ON EITHER SIDE OF LINE WHICH GOES FROM NORTH CENTRAL
FLORIDA TO NW GULF OF MEXICO NEAR 28N95W.

RIDGE WITHIN 150-200 NM ON EITHER SIDE OF LINE
THROUGH 32N26W TO 28N33W 25N45W 23N59W.

SIGNIFICANT CLOUDS/CONVECTION...
GULF OF MEXICO...
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IN NE GULF AND 
OVER FLORIDA...FROM 28N TO 31N BETWEEN 82W AND 90W... TO THE SE 
OF THE MIDDLE TO UPPER LEVEL TROUGH...WHOSE AXIS IS MOVING 
TOWARD THE OHIO RIVER VALLEY AND THE MISSISSIPPI/ALABAMA BORDER.
ISOLATED MODERATE CONVECTION ELSEWHERE NORTH OF 22N98W 23N88W 
25N81W...WEST OF 90W AROUND THE MIDDLE TO UPPER LEVEL 25N94W 
CYCLONIC CENTER...AND EAST OF 90W EAST OF MIDDLE TO UPPER LEVEL
DIFFLUENT FLOW AND LOW LEVEL SOUTHERLY WINDS.  

CARIBBEAN SEA...
SCATTERED STRONG THUNDERSTORM CELLS FROM 10N TO 12N BETWEEN 76W 
AND 78W PROBABLY NOT WITH THE 72W TROPICAL WAVE. THIN LINE OF
CONVECTIVE CELLS WITHIN 15 NM ON EITHER SIDE OF 14N BETWEEN 77W
AND 79W MIGHT BE RELATED TO SOME TYPE OF LOW LEVEL CONFLUENT
FLOW. HIGH CLOUD BUILDUPS FROM 17N TO SW HAITI COAST BETWEEN
73W AND 76W.

TROPICAL ATLANTIC...
ITCZ SHOWERS AND THUNDERSTORMS.

SUBTROPICAL ATLANTIC...
SCATTERED MODERATE TO STRONG CONVECTION IN INDIVIDUAL CELLS...
FROM 27N TO 31N BETWEEN 76W AND 79W...AND ISOLATED MODERATE TO
LOCALLY STRONG SHOWERS AND THUNDERSTORMS CUBA TO 27N BETWEEN 77W 
AND 80W...IN AREA OF FORMER MIDDLE TO UPPER LEVEL CYCLONIC CENTER
AND SURFACE TROUGH DURING THE LAST 24 HOURS. ISOLATED TO WIDELY
SCATTERED MODERATE TO LOCALLY STRONG CONVECTION IN THREE CLUSTERS
OF CONVECTIVE CELLS...FROM 25N TO 32N BETWEEN 55W AND 65W...IN
AREA OF COMPARATIVELY WEAK MIDDLE TO UPPER LEVEL CYCLONIC FLOW.
 
$$
MT