000
AXPZ20 KNHC 311006
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC SAT OCT 31 2015

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 
0945 UTC.               

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
MONSOON TROUGH AXIS EXTENDS FROM 08N83W TO 13N92W. IT RESUMES AT 
15N111W TO LOW PRES NEAR 12N126W 1011 MB TO 08N133W TO 06N140W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S 
OF THE TROUGH BETWEEN 118W-122W...AND WITHIN 60 NM SW QUADRANT 
OF LOW. SCATTERED MODERATE CONVECTION IS ELSEWHERE WITHIN 180 NM 
S OF TROUGH BETWEEN 123W AND 127W...AND ALSO WITHIN 120 NM SE OF 
TROUGH BETWEEN 130W AND 134W. 

...DISCUSSION...

A RATHER SHARP UPPER TROUGH EXTENDS FROM EASTERN NEW MEXICO SW 
ACROSS NW MEXICO AND THE SOUTHERN BAJA CALIFORNIA PENINSULA TO 
NEAR 17N123W. THE TROUGH HAS INDUCED DEEP SURFACE LOW PRES 
ACROSS MUCH OF NORTHERN AND CENTRAL MEXICO. AN ASSOCIATED 
WEAKENING SURFACE TROUGH IS ALONG A POSITION FROM 30N105W TO 
JUST TO THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA. IN 
THE WAKE OF THE TROUGH...FRESH NW WINDS ARE PRESENT ACROSS THE 
GULF OF CALIFORNIA WITH SEAS OF 3-5 FT. THESE WINDS WILL 
DIMINISH TO 10-15 KT DURING THE AFTERNOON WITH SEAS SUBSIDING TO 
2-3 FT. N-NE WINDS W OF THE BAJA CALIFORNIA PENINSULA N OF 21N 
BETWEEN 120W-133W HAVE DIMINISHED TO 15-20 KT. SEAS WITHIN THIS 
AREA OF WINDS ARE IN THE 6-8 FT RANGE. 

A NEARLY STATIONARY 1025 MB SUBTROPICAL HIGH CENTERED NEAR 
33N135W WILL BREAK DOWN SUN AS A COLD FRONT MOVES INTO THE FAR 
NW WATERS. THE FRONT WILL WEAKEN AS IT REACHES FROM NEAR 32N126W 
TO 30N140W BY EARLY MON AS IT IS OVERTAKEN BY A LARGE AREA OF 
STRONG HIGH PRES IS EXPECTED TO PRESS SOUTHWARD OVER CENTRAL 
WESTERN PORTIONS. THE RESULTANT TIGHT PRESSURE GRADIENT IS 
FORECAST TO USHER IN ANOTHER ROUND OF FRESH TO STRONG NW WINDS 
AND LARGE NW SWELL FOR THE WATERS W OF NORTHERN BAJA EARLY NEXT 
WEEK. THE 1011 MB WEAK LOW ALONG THE MONSOON TROUGH AS MENTIONED 
ABOVE IS FORECAST TO MOVE LITTLE THROUGH TONIGHT...THEN MOVE 
SLOWLY ENE THROUGH MON. THE GRADIENT BETWEEN THE LOW AND THE 
HIGH PRESSURE TO ITS N WILL KEEP NE 15-20 KT WINDS WITHIN ABOUT 
180 NM OF THE LOW IN THE N AND NE QUADRANTS...AND ELSEWHERE 
WITHIN 60 NM OF THE LOW. ANOTHER LOW IS FORECAST TO FORM ON THE 
MONSOON TROUGH NEAR 13N110W ON SUN...AND MOVE IN AN ENE  
DIRECTION.

AN AREA OF 8-10 FT COMBINED SEAS MAINLY IN NW SWELL COVERS NW 
PART OF FORECAST AREA. WAVE MODEL GUIDANCE SHOWS THE AREA OF 
SWELL SLOWLY SHRINKING IN SIZE TO AN AREA ROUGHLY N OF 10N W OF 
120W BY LATE SUN NIGHT. SW SWELL TO 7-8 FT PREVAILS OVER SE 
PART...WITH SEAS TO 8-9 FT FROM 10N-15N BETWEEN 108W-123W. 
SHRINKING AREA OF MIXED SW AND NW SWELL WILL PERSIST S OF 
MONSOON TROUGH THIS WEEKEND. 

ELSEWHERE...STRONG TO NEAR-GALE NORTHERLY WINDS EXPECTED IN GULF 
OF TEHUANTEPEC SUN NIGHT AND MON MORNING...WITH SECONDARY WEAKER 
SURGE THE FOLLOWING NEXT NIGHT.

$$
AGUIRRE