000
AXPZ20 KNHC 290914
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC THU OCT 29 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 
0830 UTC.               

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
THE MONSOON TROUGH AXIS EXTENDS FROM 11N85W TO 11N92W TO LOW 
PRES 1009 MB NEAR 13N105W TO 11N110W TO LOW PRES 1011 MB NEAR 
16N122W TO 09N133W...WHERE IT TRANSITIONS TO THE ITCZ TO 
08N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS 
NOTED WITHIN 240 NM S OF MONSOON TROUGH AXIS BETWEEN 100W AND 
120W. 

...DISCUSSION...

N OF 15N E OF 125W...AN MID/UPPER LEVEL LONG WAVE TROUGH IS 
MOVING EAST ACROSS THE SOUTHERN CALIFORNIA...BAJA CALIFORNIA 
NORTE...AND ADJACENT PACIFIC WATERS. AN ASSOCIATED SURFACE 
TROUGH IS MOVING THROUGH SOUTHERN CALIFORNIA CURRENTLY AND WILL 
LIKELY FORM INTO A WEAK COLD FRONT AS IT SHIFTS SOUTH THROUGH 
THE BAJA CALIFORNIA PENINSULA AND GULF OF CALIFORNIA THROUGH 
LATE FRI. STRONG NW TO N WINDS WILL FOLLOW THE FRONT ACROSS THE 
PACIFIC WATERS OFF OF BAJA CALIFORNIA NORTE. RESULTANT SEAS WILL 
MIX WITH LONGER PERIOD NW SWELL MOVING INTO THE AREA AS WELL. 
COMBINED SEAS WILL BUILD TO 12 TO 13 FT NEAR AND WEST OF 
GUADALUPE ISLAND...AND 7 TO 12 FT ELSEWHERE ACROSS THE WATERS 
ALONG THE ENTIRE LENGTH OF THE BAJA PENINSULA BY THIS AFTERNOON. 
STRONG WEST FLOW WILL PUNCH THROUGH RELATIVELY LOWER TERRAIN IN 
BAJA CALIFORNIA AND SPILL ACROSS THE WATERS OF THE NORTHERN AND 
CENTRAL GULF OF CALIFORNIA IN NARROW PLUMES THROUGH TONIGHT. 
THIS WILL BE FOLLOWED BY A STRONGER PUSH OF NW WINDS OVER THE 
NORTHERN GULF OF CALIFORNIA FRI...WHEN SEAS WILL BUILD TO 8 FT. 
THE DISSIPATING FRONT IS EXPECTED TO REACH THE SOUTHERN 
PENINSULA BY FRI AFTERNOON FROM CABO SAN LAZARO TO ABOUT 
21N120W..WITH STRONG NORTHERLY WINDS THEN BEGINNING TO RECEDE N 
OF 27N. FARTHER SOUTH...SCATTERED CONVECTION PERSISTS ALONG A 
SURFACE TROUGH REACHING FROM CABO CORRIENTES TO A 1009 MB 
SURFACE LOW ALONG THE MONSOON TROUGH NEAR 13N105W. THIS LOW IS 
EXPECTED TO DISSIPATE AS IT LIFTS NORTH AND DISCONNECTS FROM THE 
MONSOON TROUGH THROUGH LATE TODAY. LOOKING AHEAD...WINDS AND 
SEAS WILL SUBSIDE ACROSS THE REGION STARTING SAT AS THE NW SWELL 
DECAYS AND WEAK HIGH PRES BUILDS TO THE NORTHWEST OF THE AREA.

S OF 15N E OF 120W...SEVERAL WEAK AND SPORADIC PERTURBATIONS 
CONTINUE ALONG THE MONSOON TROUGH. WHILE SW FLOW REMAINS FAIRLY 
LIGHT TO MODERATE INTO THE MONSOON TROUGH...PERSISTENT SW SWELL 
IN THE AREA IS MAINTAINING SEAS 6 TO 7 FT. THE CONVERGING SW 
FLOW IS ALSO SUPPORTING AREAS OF CONVECTION ALONG THE MONSOON 
TROUGH BETWEEN 100W AND 120W. LOOKING AHEAD...GLOBAL MODELS ARE 
INDICATING A LOW PRES AREA BECOMING SLIGHTLY MORE ORGANIZED 
ALONG THE MONSOON TROUGH THIS WEEKEND AND DRIFTING EASTWARD TO 
NEAR 15N110W BY EARLY NEXT WEEK. THE MAIN IMPACT WILL BE SEAS TO 
9 FT IN THE FRESH SW FLOW OCCURRING NEAR AND SOUTH OF THE LOW 
PRES CENTER.

ELSEWHERE...THE REMNANT LOW OF OLAF HAS OPENED INTO A SURFACE 
TROUGH AS IT MOVED WEST OF 140W EARLIER. AN ASCAT SATELLITE PASS 
FROM 07 UTC INDICATED FRESH TO STRONG WINDS FROM 24N TO 29N WEST 
OF 135W...BETWEEN THE SURFACE TROUGH AND 1026 MB HIGH PRES 
CENTERED TO THE NORTH. IN ADDITION...OBSERVATIONS FROM THE NOAA 
SHIP OSCAR ELTON SETTE PASSING NEAR THE BASE OF THE SURFACE 
TROUGH INDICATED SEAS TO 12 FT...INDICATIVE OF LONG PERIOD NW 
SWELL MOVING INTO THE REGION. CONCURRENT ALTIMETER SATELLITE 
PASSES SHOW NW SWELL IN EXCESS OF 8 FT REACHING AS FAR EAST AS 
125W AND AS FAR SOUTH AS 20N SO FAR. FARTHER SOUTH...A WEAK 1011 
MB SURFACE LOW ALONG THE MONSOON TROUGH NEAR 16N122W. AN ASCAT 
PASS FROM 05 UTC SHOWED WINDS TO 20 KT WITHIN 120 NM ON THE 
NORTH QUADRANT OF THE LOW PRES. AN EARLIER ALTIMETER PASS 
INDICATED SEAS TO 8 FT IN THIS AREA AS WELL. THE NW SWELL IS 
RAPIDLY OVERTAKING AND MIXING WITH THE LOCALLY GENERATED SEAS IN 
THIS AREA.  THE LOW WILL DRIFT WEST TO 13N115W BY LATE 
FRIDAY...WHERE IT WILL SUPPORT STRONG SW WINDS ON ITS SOUTHERN 
FLANK WITH SEAS TO 9 FT IN MIXED SW AND NW SWELL. LOOKING 
AHEAD...THE NW SWELL WILL GRADUALLY DECAY BELOW 8 FT THROUGH 
EARLY NEXT WEEK AS THE LOW PRES NEAR 13N115W WILL CONTINUE EAST 
AND MERGE WITH THE LOW NEAR 15N110W ALONG THE MONSOON TROUGH. 

$$
CHRISTENSEN