000
AXPZ20 KNHC 041532
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC WED NOV 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.               

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
THE MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 10N95W TO LOW 
PRES 1009 MB NEAR 09N99W TO 05N110W...WHERE IT IS DISCONTINUOUS 
AND RESUMES AT LOW PRES 1008 MB NEAR 15N110W TO LOW PRES 1009 MB 
NEAR 14N117W TO 09125W. SCATTERED MODERATE CONVECTION IS NOTED 
WITHIN 150 NM S OF MONSOON TROUGH AXIS BETWEEN 80W AND 95W. 
SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 120 NM 
EITHER SIDE OF AXIS BETWEEN 100W AND 110W. SCATTERED MODERATE 
CONVECTION NOTED WITHIN 90 NM N OF AXIS BETWEEN 110W AND 112W.

...DISCUSSION...

N OF 15N E OF 120W...A SHARP UPPER TROUGH EXTENDS FROM THE 
NORTHERN ROCKIES TO SOUTHERN CALIFORNIA...THEN TOWARD THE 
SOUTHWEST AS A BROAD UPPER TROUGH TO 20N140W. AN ASSOCIATED COLD 
FRONT CONTINUES TO MOVE SOUTHWARD ACROSS THE REGION...REACHING 
FROM THE SOUTHERN ROCKIES ACROSS BAJA CALIFORNIA SUR TO 
21N120W. GENERALLY MODERATE TO FRESH NW FLOW FOLLOWS THE FRONT 
ALONG THE PACIFIC COAST OF THE BAJA CALIFORNIA PENINSULA...BUT 
THERE ARE LOCALIZED AREAS OF 20 TO 25 KT AS NOTED IN SHIP 
OBSERVATIONS FROM EARLIER THIS MORNING. FRESH TO STRONG WEST 
WINDS ARE ONGOING OVER PORTIONS OF THE FAR NORTHERN GULF OF 
CALIFORNIA BETWEEN 1004 MB LOW PRES OVER THE COLORADO RIVER AND 
THE SUBTROPICAL RIDGE OFF THE COAST OF BAJA CALIFORNIA NORTE. 
THE UPPER TROUGH LIFTS NORTH OF THE AREA THROUGH THU ALLOWING 
THE COLD FRONT TO STALL AND DISSIPATE...ALLOWING WINDS TO 
DIMINISH. SEAS ARE 6 TO 8 FT OFF THE BAJA COAST IN NW SWELL. 
THIS WILL SUBSIDE THROUGH THU EXCEPT LINGERING TO 8 FT WEST OF 
CLARION ISLAND. FARTHER SOUTH A SCATTERED SHOWERS AND 
THUNDERSTORMS ARE ONGOING NEAR WEAK LOW PRES AT 15N110W. LOOKING 
AHEAD...THERE IS SOME UNCERTAINTY IN MODEL OUTPUT WITH REGARD TO 
FRESH TO STRONG WINDS OVER THE CENTRAL AND SOUTHERN GULF OF 
CALIFORNIA FRI INTO SAT AS ANOTHER MID/UPPER IMPULSE MOVES 
ACROSS THE ROCKIES. THE GFS REMAINS MOST AGGRESSIVE WITH 
THIS...BUT OTHERWISE MODEL CONSENSUS SHOWS GENERALLY 15 TO 20 KT 
WINDS WITH 5 TO 7 FT SEAS.

GULF OF TEHUANTEPEC...THE STRONG N-NE GAPS WINDS THAT OCCURRED 
YESTERDAY HAVE DIMINISHED TO 20 KT OR LESS...HOWEVER A QUICK 
SURGE OF N-NE 20-25 KT WINDS IS EXPECTED EARLY THIS EVENING INTO 
LATE TONIGHT BEFORE DIMINISHING AGAIN TO 20 KT OR LESS THU 
AFTERNOON. LINGERING SECONDARY SWELL WILL PRODUCE SEAS OF 8 FT FROM 
13N-15N BETWEEN 95W-97W THU AFTERNOON INTO THU NIGHT. LOOKING 
AHEAD...STRONGER GAP WIND EVENT IS ANTICIPATED FROM EARLY SAT 
THROUGH SUN.
 
S OF 15N W OF 110W...AN UPPER LOW IS CENTERED OVER HONDURAS WITH 
A SHARP TROUGH EXTENDING FROM THE LOW TO ROUGHLY 10N100W. THIS 
IS SUPPORTING AREAS OF CONVECTION ALONG AND SOUTH OF THE MONSOON 
TROUGH BETWEEN 80W AND 110W. WEAK LOW PRES WILL PERSIST ALONG 
THE MONSOON TROUGH BETWEEN 100W AND 105W THROUGH 48 HOURS. THIS 
WILL SUPPORT 15 TO 20 KT SW FLOW INTO THE MONSOON TROUGH WHICH 
IN TURN WILL KEEP SEAS TO 8 FT WITHIN 240 NM S OF THE LOW PRES 
WITH THE ADDED COMPONENT OF SW SWELL LINGERING IN THE AREA. 
LOOKING AHEAD...SEAS WILL DIMINISH TO 5 TO 7 FT W OF 90W AS THE 
SWELL DECAYS AND THE LOW WEAKENS.

ELSEWHERE...DEEP LAYER RIDGING WILL BUILD ACROSS THE SUBTROPICS 
IN THE WAKE OF THE COLD FRONT. THIS WILL SUPPORT AN AREA OF 
FRESH TO STRONG TRADE WINDS BETWEEN 15N AND 22N W OF 130W 
THROUGH LATE THU. SUCCESSIVE ALTIMETER PASSES FROM EARLIER THIS 
MORNING SHOWED 8 TO 12 FT SEAS OVER MUCH OF THE AREA N OF 12N 
AND W OF 120W...DUE MOSTLY TO LONG PERIOD NW SWELL PERSISTING 
ACROSS THE REGION. THIS WILL DECAY BELOW 8 FT THROUGH LATE 
THU...LEAVING 8 TO 10 FT SEAS FROM 12N TO 22N W OF 120W IN MIXED 
NW SWELL AND NE WIND WAVES. LOOKING AHEAD...THE SUBTROPICAL 
RIDGE WILL WEAKEN STARTING LATE FRI AHEAD OF ANOTHER DEEP LAYER 
TROUGH APPROACHING FROM THE N CENTRAL PACIFIC. THIS WILL ALLOW 
WINDS AND SEAS TO DIMINISH IN THE DEEP TROPICS...BUT INTRODUCE 
ANOTHER ROUND OF NW SWELL 8 TO 9 FT INTO THE NW CORNER OF THE 
DISCUSSION AREA BY EARLY SUN.

$$
CHRISTENSEN