000
AXPZ20 KNHC 280941
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU SEP 28 2006

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 
0830 UTC.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...9N83W 9N95W 18N112W 10N125W 9N130W 
10N140W. SCATTERED MODERATE CONVECTION WITHIN 180 NM  BETWEEN 110W 
AND 135W.

TROPICAL WAVES...
TROPICAL WAVE NEAR 84W MOVING W 10 TO 15 KT.

A NEARLY STATIONARY 1011 MB LOW IS CENTERED NEAR 12N122W. ISOLATED 
MODERATE CONVECTION WITHIN 180 NM N SEMICIRCLE.
  
...DISCUSSION...
UPPER TROUGH FROM 30N128W TO 14N129W WILL CONTINUE TO LIFT OUT AS AN 
UPPER RIDGE CENTERED OFF MEXICO NEAR 21N110W BUILDS W. WEAK LOW 
PRESSURE NEAR 12N122W STILL FEEDING ON THE UPPER DIVERGENCE ON THE 
WRN PERIPHERY OF THE RIDGE BUT CONTINUES TO WEAKEN AS IT MOVES INTO 
LESS FAVORABLE REGIME UNDER UPPER TROUGH. STATIONARY BOUNDARY LAYER 
RIDGE REMAINS CENTERED NEAR 30N123W. TIGHT GRADIENT BETWEEN THIS 
RIDGE AND THE LOW AT 12N122W IS RESULTING IN PERSISTENT FRESH NE 
TRADES FROM 13N AND 20N BETWEEN 120W AND 140W.

NEARLY STATIONARY UPPER LOW CENTERED NEAR 9N103W WITH ONLY MINIMAL 
CONVECTION NOTED ALONG IS NRN AND WRN PERIPHERY. 

COMBINATION OF HIGH PRESSURE BUILDING OVER THE WESTERN GULF OF 
MEXICO AND THE APPROACHING TROPICAL WAVE ARE SETTING UP ANOTHER GAP 
WIND SITUATION IN TEHUANTEPEC AREA. THIS IS CONFIRMED BY LATEST 
OBSERVATIONS FROM COATZACOALCOS AND IXTEPEC MEXICO SHOWING RETURN OF 
20 KT SUSTAINED GAP WINDS. A QUIKSCAT PASS FROM YESTERDAY EVENING 
ALSO SHOWS 20 KT WINDS IN GULF OF TEHUANTEPEC. GFS IS INITIALIZES 
THIS SITUATION WELL...AND IS SHOWING THE WINDS STAYING AT OR JUST 
ABOVE 20 KT FOR AT LEAST THE NEXT 72 HOURS. THIS MAY BE A LITTLE 
GENEROUS CONSIDERING THAT THE RIDGE OVER THE WESTERN GULF WILL 
WEAKEN AND SHIFT EAST OVER THE NEXT 48 HOURS. WILL MENTION THE WINDS 
IN THE HIGH SEAS FORECAST FOR AT LEAST THE NEXT 48 HOURS...BUT NOT 
CONFIDENT THE EVENT WILL PERSIST MUCH MORE THAN THAT ATTM. 

S OF 10N LIGHT TO MODERATE CROSS-EQUATORIAL SLY FLOW PERSISTS 
ACCOMPANIED BY MODERATE TO LARGE SW SWELL BETWEEN 92W AND 122W. THE 
SLY FLOW IS CONVERGING WITH DRAINAGE WINDS OFF PANAMANIAN AND COSTA 
RICAN COASTS TO TRIGGER MODERATE CONVECTION GENERALLY N OF 7N AND E 
OF 86W. 

$$
CHRISTENSEN