000
AXPZ20 KNHC 201523
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED NOV 20 2013

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.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
THE MONSOON TROUGH EXTENDS FROM 8N78W 9N95W 7N95W TO 6N110W 
WHERE THE ITCZ BEGINS AND CONTINUES ALONG 5N115W 6N119W 5N130W 
TO 7N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 
WITHIN 150 NM S OF MONSOON TROUGH BETWEEN 84W-87W...WITHIN 90 NM 
S OF MONSOON TROUGH BETWEEN 91W-104W...AND  WITHIN 90 NM N OF 
MONSOON TROUGH BETWEEN 96W-100W. 


...DISCUSSION...                                                
RELATIVELY TRANQUIL WEATHER CONDITIONS PERSIST ACROSS THE 
DISCUSSION AREA THIS MORNING. A WEAKENING 1019W MB HIGH ANALYZED 
OVER THE NW PART OF THE AREA NEAR 26N134W WITH ASSOCIATED RIDGE 
EXTENDING SE TO NEAR 16N112W. DUE TO THE RELATIVE WEAK HIGH 
PRESSURE CENTER...THE PRESSURE GRADIENT BETWEEN THIS FEATURE AND 
LOWER PRESSURE IN THE VICINITY OF THE ITCZ...AS WELL AS LOW 
PRESSURE ACROSS THE W SLOPES OF THE SIERRA MADRE OCCIDENTALES... 
REMAINS WEAK. WINDS OFFSHORE OF BAJA CALIFORNIA AND SW MEXICO 
WERE GENERALLY N TO NW AT AROUND 15 TO 20 KT WITH 15 TO 20 KT 
TRADE WINDS N OF THE ITCZ. THIS HIGH PRESSURE CENTER WILL 
CONTINUE TO WEAKEN AND COLLAPSE AS IT SHIFTS WESTWARD OVER THE 
NEXT 24 HOURS. STRONGER HIGH PRESSURE WELL N OF THE AREA WILL 
BUILD SOUTHWARD OVER THE NEXT COUPLE OF DAYS. THE PRESSURE 
GRADIENT BETWEEN THIS STRONGER HIGH PRESSURE CENTER AND LOW 
PRESSURE OVER THE W CONUS WILL PRODUCE GALE FORCE WINDS N OF THE 
AREA WHICH WILL GENERATE A LARGE N SWELL THAT WILL PROPAGATE 
INTO THE AREA LATE THU INTO FRI. 

LOOKING AHEAD...A STRONG COLD FRONT IS EXPECTED TO MOVE ACROSS 
THE GULF OF MEXICO THIS WEEKEND. RESULTANT WINDS FUNNELING 
THOUGH THE CHIVELA PASS INTO THE GULF OF TEHUANTEPEC WILL 
PRODUCE THE NEXT SIGNIFICANT GAP WINDS EVENT. WINDS OVER THE 
GULF OF TEHUANTEPEC ARE EXPECTED TO REACH GALE FORCE BY LATE SAT 
INTO SUN. 

$$
PAW