000
AXPZ20 KNHC 210953
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED MAR 21 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0915 UTC.

...ITCZ...

ITCZ IS CENTERED ALONG...5N78W 6N87W 5N101W 3N110W 4N120W
5N130W 3N140W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM
EITHER SIDE OF ITCZ BETWEEN 103W-109W...AND ALSO WITHIN 30 NM
EITHER SIDE OF ITCZ BETWEEN 92W-97W. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF ITCZ BETWEEN
118W-127W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF
ITCZ BETWEEN 109W-112W.

...DISCUSSION...

A FAST MOVING MID/UPPER LEVEL TROUGH EXTENDS FROM NEVADA AND 
SRN CALIFORNIA SW INTO THE DISCUSSION AREA AT 32N122W AND
STRETCHES TO 27N127W TO 24N136W. A THIN BAND OF UPPER LEVEL
MOISTURE IS SEEN WITHIN 120 NM E OF THE TROUGH N OF 24N...
OTHERWISE MODERATE SUBSIDENCE AND DRY UPPER AIR IS SEEN FROM 
23N-29N. AN AREA OF UPPER LEVEL ANTICYCLONIC FLOW IS SPREADING
INTO THE NW PORTION OF THE DISCUSSION AREA BEHIND THE TROUGH.

AN UPPER LEVEL ANTICYCLONE IS NEAR 5N128W WITH ITS ENVELOPE OF 
ANTICYCLONIC FLOW DOMINATING THE REMAINDER OF THE AREA W OF 
108W. ANOTHER UPPER TROUGH EXTENDS FROM THE NW CARIBBEAN SSW OVER
THE FAR E PORTION OF THE AREA FROM ROUGHLY ALONG 13N89W TO 
7N90W. THE TROUGH IS HELPING SET OFF SMALL CLUSTERS OF SCATTERED
STRONG CONVECTION ALONG THE ITCZ BETWEEN 92W-95W. THIS TROUGH
IS FORECAST TO MOVE E ACROSS CENTRAL AMERICA AND TO THE CARIBBEAN
SEA IN ABOUT 18-24 HOURS. MID/UPPER LEVEL RIDGING PRESENT OVER
COLOMBIA AND VENEZUELA ALONG 7N EXTENDS WWD TO 81W. SCATTERED
STRONG CONVECTION IS ALONG THE COAST OF COLOMBIA S OF 6N. A 
MOISTURE PLUME...ORIGINATING FROM THE DEEP TROPICS W OF THE AREA 
CONTINUES TO RIDE NEWD AROUND THE NW PERIPHERY OF THE 
ANTICYCLONIC FLOW ASSOCIATED WITH THE ANTICYCLONE NEAR 5N128W. 
THE PLUME REACHES NEWD AS FAR AS BAJA CALIFORNIA AND NRN MEXICO 
AND WRN TEXAS. MODERATE SUBSIDENCE AND RELATED DRY AIR IS 
GENERALLY OBSERVED ACROSS THE REMAINDER OF THE DISCUSSION AREA. 
AN UPPER DIFFLUENT PATTERN IS EVIDENT TO THE SE OF THE 
ANTICYCLONE BETWEEN 113W-125W. AS A RESULT...ITCZ CONVECTION 
HERE HAS FLARED UP IN CLUSTERS...AND APPEARS QUITE HEALTHY 
EXHIBITING SCATTERED MODERATE/ISOLATED INTENSITY.

AT THE SURFACE...A RIDGE EXTENDS SE INTO THE AREA THROUGH 32N138W
AND THROUGH 25N125W TO 19N113W. HIGH PRES COVERS THE AREA N OF 
14N AND W OF 113W. SCATTERED TO BROKEN STRATOCUMULUS CLOUDS
WITH POSSIBLE ISOLATED SHOWERS ARE MOVING SW TO W N OF 22N AND
W OF 121W.

GAP WINDS...MODEL GUIDANCE SUGGEST THAT 20-25 KT SHOULD ALREADY
BE OCCURRING IN THE GULF OF TEHUANTEPEC...HOWEVER...BASED ON 
SURFACE OBSERVATIONS FROM JUST INLAND THE GULF AND LOOKING AT A 
QUIKSCAT PASS FROM 0044 UTC LAST NIGHT I SEE N WINDS LESS THAN 
20 KT BUT MORE IN THE RANGE OF 10-15 KT. SINCE MODELS ALSO 
SUGGEST THAT HIGH PRES WILL BE BE RATHER WEAK OVER SE MEXICO 
THROUGH THE NEXT 36 HOURS...WILL INTRODUCE NLY WINDS AT 20 KT TO 
BEGIN IN 12 HOURS OVER THE GULF THEN DIMINISH THU NIGHT. TIGHT 
PRES GRADIENT OVER THE W CARIBBEAN IS SPILLING ACROSS CENTRAL 
AMERICA WITH NE WINDS OF 20-25 KT INTO AND DOWNSTREAM OF THE 
GULF OF PAPAGAYO. LATEST MODEL GUIDANCE INDICATES LITTLE CHANGE 
THROUGH 24 HOURS THEN GRADIENT RELAXES SUPPORTING NE 20 KT WINDS 
IN 48 HOURS.

$$
AGUIRRE