000
AXPZ20 KNHC 010245
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON OCT 01 2012

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0130 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

MONSOON TROUGH EXTENDS FROM NEAR 14.5N84W TO DEVELOPING LOW PRES 
NEAR 10N97W 1010 MB TO 08N104W TO 12N109W WHERE IT REMAINS 
FRACTURED...THEN RESUMES FROM LOW PRES NEAR 14N115W 1011 MB TO 
12N125W WHERE IT TRANSITIONS TO ITCZ...CONTINUING ON TO BEYOND 
11N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED FROM 
06.5N TO 10N E OF 88W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION NOTED WITHIN 90 NM N AND 240 NM S OF TROUGH E OF 
106W.

...DISCUSSION...

BROAD UPPER RIDGE ACROSS THE AREA CENTERED ON ANTICYCLONE NEAR 
22N114W EXTENDS W TO 125W AND E ACROSS CENTRAL MEXICO...AND 
SEPARATES TWO UPPER LEVEL TROUGHS TO THE NE ALONG 98W-99W...AND 
TO THE NW ALONG 133W-134W. S/W TROUGH DROPPING INTO BACKSIDE OF 
CENTRAL U.S. TROUGH IS ALLOWING UPPER RIDGE TO SLOWLY BEGIN TO 
BUILD NWD OF 30N ALONG BAJA AND SOUTHERN CALIFORNIA COASTS. THE 
PATTERN IS FORECAST TO AMPLIFY NEXT FEW DAYS AS CENTRAL U.S. 
TROUGH DIGS S AND S INTO NW GULF OF MEXICO. VIGOROUS TUTT LOW 
OVER NW CARIBBEAN EXTENDS TUTT AXIS SW ACROSS CENTRAL AMERICA 
THEN WSW TO NEAR 08N105W. UPPER LEVEL DEFORMATION ZONE HAS 
DEVELOPED BETWEEN TUTT LOW AND W END OF TUTT YIELDING GOOD UPPER 
DIVERGENCE ACROSS MONSOON TROUGH BETWEEN 92W AND 102W... 
SUPPORTING CONVECTION DESCRIBED ABOVE. TUTT TO GRADUALLY WEAKEN 
MON AND PRODUCE STABILIZING CONDITIONS ALOFT BETWEEN 90W AND 
100W BY LATE AFTERNOON AND EVENING.  

A STRONG NE-SW ORIENTED HIGH PRES RIDGE REMAINS WELL N AND NW OF 
THE DISCUSSION AREA...EXTENDING FROM A 1031 MB HIGH WELL 
OFFSHORE OF OREGON NEAR 44N133W TO 24N155W. A WEAK RIDGE 
PREVAILS OVER THE TROPICAL EAST PACIFIC N OF 15N W OF 118W. THE 
LOW PRES REMNANT OF MIRIAM CAN CLEARLY BE SEEN IN SATELLITE 
IMAGERY DRIFTING SSW...AND BARELY HANGING ON AS NOTEWORTHY 
SURFACE FEATURE NEAR 18.5N114.5W...WITH RECENT SCATTEROMETER 
WINDS SHOWING 10-15 KT WINDS ACROSS THE W SEMICIRCLE. MARINE 
CONDITIONS ARE FAIRLY BENIGN OVER REST OF THE DISCUSSION AREA AS 
TRADEWINDS ARE LIGHT TO MODERATE DUE TO WEAK HIGH PRES...AND THE 
MONSOONAL SWLY WINDS ARE GENERALLY 15 KT AND LESS. SEAS E OF 
120W THEREFORE CONTINUE TO SUBSIDE AND ARE GENERALLY AROUND 6-7 
FT OVER MOST OF THE DISCUSSION AREA... EXCEPT FROM 05N TO 11N 
BETWEEN 92W AND 105W WHERE SW SWELL DOMINATES...AND ACROSS N 
PORTIONS WHERE FRESH NE WINDS N OF THE AREA AND LINGERING LONG 
PERIOD NW SWELL ARE PRODUCING SEA HEIGHTS 8 TO 9 FT NW OF A LINE 
FROM 30N119W TO 26N119W TO 15N140W. SEAS WILL SUBSIDE BELOW 8 FT 
ACROSS BOTH THESE AREAS WITHIN 36 HOURS.

A COLD FRONT IS MOVING ACROSS THE NW GULF OF MEXICO TONIGHT AND 
IS EXPECTED TO SWEEP ACROSS ALL BUT THE SE GULF EARLY THIS WEEK. 
HIGH PRES BUILDING BEHIND THE FRONT OVER SOUTHERN MEXICO WILL BE 
A FAVORABLE SET UP FOR A MINOR GULF OF TEHUANTEPEC GAP WIND 
EVENT...EXPECTED TO COMMENCE EARLY TUE. NLY WINDS AROUND 20 KT 
WILL BEGIN TO SPILL OUT OF THE GULF OF MEXICO ACROSS THE 
CHIVELAS PASS AND THROUGH THE GULF OF TEHUANTEPEC TUE MORNING... 
THEN INCREASE TO 20-25 KT LATER ON TUE. THIS GAP WIND FLOW IS 
THEN EXPECTED TO PULSE TO 20-30 KT IN THE EARLY MORNINGS HOURS 
ON EACH SUCCESSIVE DAY THROUGH AT LEAST THU....BUILDING 
DOWNSTREAM SEAS TO 8-10 FT BY EARLY THU.

$$
STRIPLING