000
AXPZ20 KNHC 141513
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE NOV 14 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1445 UTC.

...SPECIAL FEATURE...

TROPICAL STORM SERGIO IS CENTERED NEAR 13.2N 104.5W...OR 350 NM 
SW OF ACAPULCO MEXICO...AT 14/1500 UTC MOVING NW 3 KT. MAXIMUM 
SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. ESTIMATED 
MINIMUM CENTRAL PRESSURE IS 1006 MB. THE LONG CONVECTIVE BAND 
THAT SERGIO HAD OVERNIGHT HAS DISSIPATED IN FAVOR OF MORE 
CONCENTRATED CONVECTION NEAR THE CENTER...WHICH IS STRONG AND 
ORGANIZED ENOUGH TO WARRANT UPGRADING THE SYSTEM TO A TROPICAL 
STORM. SERGIO SITS BENEATH AN UPPER RIDGE AND THEREFORE IS 
EMBEDDED WITH A FAVORABLE ENVIRONMENT OF UPPER DIFFLUENCE... 
ESPECIALLY OVER THE NE QUADRANT. SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION FROM 9N-15N BETWEEN 103W-108W. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC 
FOR MORE DETAILS.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N77W 8N88W 13N100W 13N115W 7N126W 
8N140W. SCATTERED MODERATE CONVECTION N OF 3N E OF 82W. 
SCATTERED MODERATE WITHIN 120 NM S OF THE AXIS BETWEEN 82W-90W. 
SCATTERED MODERATE FROM 12N-16N BETWEEN 98W-101W. SCATTERED 
MODERATE FROM 5N-8N W OF 138W.

...DISCUSSION...

STRONG HIGH PRES IS CENTERED N OF AREA NEAR 32N136W WITH A LARGE 
AREA OF DRY AIR MOVING FROM THE BAJA PENINSULA WWD TO 140W N OF 
20N. THIS AREA IS ALSO COVERED BY A MID/UPPER LEVEL HIGH 
CENTERED NEAR 27N126W AND ITS ASSOCIATED FIELD OF 
MODERATE/STRONG SUBSIDENCE. TO THE S...AN TROUGH MAINLY LOCATED 
IN THE UPPER LEVELS EXTENDS ALONG 10N138W 20N127W WITH A 
POSSIBLE CLOSED LOW DEVELOPING NEAR 15N136W. THE TROUGH IS 
CAUSING CIRRUS FROM ITCZ CONVECTION TO STREAM NE TOWARDS THE W 
COAST OF MEXICO...BUT THE CONVECTION ITSELF IS NOT REALLY BEING 
ENHANCED AT THIS TIME. WATER VAPOR IMAGERY INDICATES THAT THE 
DEEP-LAYERED MOISTURE LIES ROUGHLY WITHIN 350 NM OF AN UPPER 
RIDGE AXIS WHICH EXTENDS FROM NEAR T.S. SERGIO WSW TO 
10N130W...BOUNDED BY DRY AIR FROM A UPPER LEVEL SHORTWAVE TROUGH 
SKIRTING ACROSS NRN MEXICO.

OVER THE FAR E PACIFIC...TROPICAL STORM SERGIO IS STRENGTHENING 
SW OF ACAPULCO AS IT ATTEMPTS TO DETACH FROM THE ITCZ. ANOTHER 
LOW-LEVEL CYCLONIC GYRE IS LOCATED JUST OFF THE SW COAST OF 
COSTA RICA NEAR 8N87W WITH A CIRCULATION WHICH EXTENDS BETWEEN 
THE COAST OF COLOMBIA AND NW TO GUATEMALA. A LARGE AREA OF DRY 
AIR LIES BETWEEN THIS GYRE AND T.S. SERGIO...PRODUCING FAIR 
WEATHER ALONG THE COAST BETWEEN THE GULF OF TEHUANTEPEC AND THE 
NICOYA PENINSULA OF COSTA RICA...AND SWD OVER THE PACIFIC WATERS 
TO 9N.

A TEHUANTEPEC WIND EVENT IS EXPECTED TO BEGIN BY THU MORNING 
WITH WINDS INCREASING TO 20 KT...THEN POTENTIALLY INCREASING TO 
GALE FORCE BY THU AFTERNOON. THESE GALE CONDITIONS COULD LAST 
FOR ABOUT 24 HRS.

$$
BERG