000
AXNT20 KNHC 041804
TWDAT 
TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON JUN 04 2007
TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1745 UTC.
...TROPICAL WAVES...
E ATLC TROPICAL WAVE IS ALONG 20W/21W S OF 10N MOVING W NEAR 15 
KT. HAVE NUDGED THIS WAVE W A BIT FROM ITS PREVIOUS 
POSITION...BUT HAVE KEPT THE WAVE JUST E (ON THE UPSHEAR SIDE) 
OF THE SCATTERED MODERATE CONVECTION NOTED FROM 3N-7N BETWEEN 
22W-30W. ISOLATED SHOWERS/TSTMS ARE ELSEWHERE WITHIN 90NM OF THE 
WAVE...MAINLY FROM 4N-7N. SATELLITE HOVMOLLER DIAGRAMS HAVE 
SHOWN A CLEAR WWD MOVING AREA OF SHOWERS/TSTMS OVER THE LAST FEW 
DAYS WITH THIS FEATURE. THE DAKAR RAOB HAS NOT SHOWN MUCH SIGNAL 
BUT SUSPECT THE WAVE DOES NOT EXTEND FAR ENOUGH POLEWARD TO SEE 
MUCH THERE. 
TROPICAL WAVE PREVIOUSLY ALONG 37W HAS BEEN REPOSITIONED TO 45W 
S OF 10N. THE WAVE CAN BE TRACED BACK TO THE CONVECTION THAT 
MOVED OFF OF AFRICA ON THE LAST DAY OF MAY. THIS WOULD MEAN THE 
WAVE IS MOVING ROUGHLY 18 KT BUT HAVE LOW CONFIDENCE IN THAT 
VALUE. OTHER REASONING FOR RELOCATING THIS WAVE IS DUE TO THE 
NEARBY CYCLONIC CURVATURE NOTED IN SATELLITE DERIVED WINDS FROM 
THE 600-800 MB LAYER. THE WAVE PLACEMENT IS ALSO ALIGNED WITH A 
POLEWARD INFLECTION POINT IN THE ITCZ. SCATTERED SHOWERS AND 
TSTMS ARE FROM 5N10N BETWEEN 40W-50W. 
A LOW AMPLITUDE TROPICAL WAVE IS MAINLY INLAND OVER SOUTH 
AMERICA ALONG 60W S OF 9N. WAVE PASSAGE WAS NOTED ABOUT 0600 UTC 
JUNE 2 AT THE CAYENNE FRENCH GUIANA RAOB WHICH WOULD INDICATE 
THE WAVE IS MOVING W NEAR 15 KT. A LOOP OF A DAYS WORTH OF 
SATELLITE IMAGERY SHOWS A SURGE OF CLOUDINESS WITH SCATTERED 
SHOWER/TSTM ACTIVITY NOW MOVING INTO ERN VENEZUELA. 
CARIBBEAN TROPICAL WAVE IS ALONG 79W S OF 15N MOVING W NEAR 10 
KT. CYCLONIC SWIRL OF LOW CLOUDS NOTED FROM 10N-15N BETWEEN 
76W-82W. LIGHTNING DATA SUPPORTS ISOLATED TSTMS IN THIS REGION 
AS WELL. THE WAVE IS ALIGNED WELL WITH A UW-CIMMS SATELLITE 
DERIVED 850 MB POSITIVE VORTICITY MAXIMUM. 
...ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N10W 5N18W 5N25W 7N42W 7N57W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-10N 
BETWEEN 10W-17W. SCATTERED MODERATE WITHIN 60NM EITHER SIDE OF 
AXIS BETWEEN 30W-36W...AND ALSO S OF 10N W OF 50W. 
...DISCUSSION...
GULF OF MEXICO...
A WEAK SFC RIDGE IS DOMINATING THE GULF THIS AFTERNOON EXTENDING 
W ALONG 24N. SOME WEAK TROUGHING IS NOTED JUST OFF THE TEXAS 
COAST BUT OVERALL RIDGING IS EXPECTED TO BE THE MAIN FEATURE 
OVER THE NEXT COUPLE OF DAYS. SCATTERED SHOWERS AND TSTMS ARE 
AFFECTING SE LOUISIANA THROUGH ALABAMA...AND ADJACENT WATERS N 
OF 29N BETWEEN 87W-93W. THE ONLY OTHER SIGNIFICANT WEATHER LIES 
IN THE YUCATAN CHANNEL...WHERE NUMEROUS SHOWERS/TSTMS EXIST 
ASSOCIATED WITH A REMNANT FRONTAL TROUGH FROM THE ATLC. WLY FLOW 
ALOFT IS OVER THE BASIN N OF AN UPPER RIDGE OVER THE NW 
CARIBBEAN. 
CARIBBEAN SEA...
MODERATE TO FRESH TRADES DOMINATE E OF 77W. FLOW BENDS MORE SE 
AND RELAXES IN THE NW PORTION AROUND THE SW PERIPHERY OF AN ATLC 
RIDGE. TROPICAL WAVE OVER THE SW PORTION...SEE ABOVE. THE MOST 
ACTIVE WEATHER IN THE BASIN IS OVER THE YUCATAN CHANNEL/FAR NW 
CARIBBEAN AS DESCRIBED IN THE GULF SECTION. BROAD ANTICYCLONIC 
FLOW DOMINATES THE CARIBBEAN AROUND AN UPPER HIGH NEAR 18N80W. 
MODERATE TO FRESH TRADES EXPECTED OVER MUCH OF THE BASIN THROUGH 
MID WEEK EXCEPT FAR SW PORTION.
ATLANTIC OCEAN...
CONDITIONS ARE FAIRLY TRANQUIL IN THE WRN ATLC WITH ABUNDANT 
SUNSHINE AND OFFSHORE FLOW. THE EXTRATROPICAL FORM OF BARRY IS 
NOW MOVING NE INTO NEW ENGLAND. A TRAILING FRONTAL TROUGH ENTERS 
THE AREA NEAR 30N69W AND CONTINUES SW TO THE WRN BAHAMAS NEAR 
23N79W. LIGHTNING AND SATELLITE DATA DEPICT SCATTERED SHOWERS 
AND TSTMS WITHIN 120NM MAINLY AHEAD OF THIS BOUNDARY. CENTRAL 
ATLC IS DOMINATED BY VERTICALLY STACKED RIDGING...WITH A 1026MB 
SFC HIGH NEAR 31N54W. A BROAD UPPER TROUGH IS EXTENDING SW ALONG 
29N47W TO THE DEEP TROPICS NEAR 11N59W. SCATTERED 
SHOWERS/ISOLATED TSTMS WITH THIS POSSIBLE IN THE ISOLATED 
MODERATE CONVECTION FROM 20N-25N BETWEEN 45W-55W. SRN PERIPHERY 
OF A 1026MB HIGH S OF THE AZORES NEAR 34N30W IS DOMINATED THE E 
ATLC SFC PATTERN...PRODUCING WIDESPREAD LIGHT TO MODERATE TRADES 
AND FAIR WEATHER E OF 40W.  
$$
WILLIS