000
AXPZ20 KNHC 041005
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON OCT 04 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

AXIS EXTENDS FROM 10N85W TO LOW PRES NEAR 10N104W TO 10N130W TO 
LOW PRES NEAR 11N140W. SCATTERED MODERATE CONVECTION WITHIN 60 NM
OF 8.5N103W.

...DISCUSSION...

ALOFT...
NEGATIVELY TILTED TROUGH EXTENDS ALONG THE COAST OF CALIFORNIA 
COAST TO 32N120W. WEAK RIDGE EXTENDS SE FROM ANTICYCLONE NEAR 
15N117W TO ANTICYCLONE NEAR 8N101W. WEAK TROUGH N OF THE RIDGE 
EXTENDS SSW FROM CENTRAL MEXICO TO NEAR 15N107W. WATER VAPOR 
IMAGERY SHOWS VERY LITTLE MID/UPPER LEVEL MOISTURE EXCEPT IN 
IMMEDIATE VICINITY OF THE THE TWO ANTICYCLONES NOTED ABOVE AND 
IN AN AREA OF MODERATE DIVERGENCE NEAR 11N136W. GFS MODEL SHOWS 
THE NEGATIVELY TILTED TROUGH PINCHING OFF CUT-OFF LOW TUE OVER 
NORTHERN CALIFORNIA AS AN OMEGA BLOCK PATTERN TRIES TO DEVELOP.

SURFACE...
SSW MONSOON FLOW CONTINUES OVER A LARGE PORTION OF THE AREA S OF 
ITCZ AXIS E OF 110W. CONVERGENCE NEUTRAL POINT BETWEEN MONSOON 
WINDS AND TEHUANTEPEC GAP WINDS NEAR 09N98W CREATING TWO WEAK 
SYMPATHETIC CYCLONIC CIRCULATIONS ON EITHER SIDE OF NEUTRAL 
POINT NEAR 11N104W AND 10N92W. WEAK LOW PRES NEAR 11N140W MOVES 
SLOWLY W OUT OF THE AREA NEXT 12 HOURS. PRES GRADIENT BETWEEN LOW
AND HIGH PRES NW OF AREA CREATING AREA OF 20 KT WINDS AND HIGHER 
SEAS IN N SEMICIRCLE. GRADIENT WILL WEAKEN OVER THE NEXT 24 HOURS
AND SEAS WILL DIMINISH TO 8-9 FT BY TUE MORNING. CUT-OFF UPPER 
LOW OVER CALIFORNIA REFLECTED AS A SURFACE LOW TUE AND WED NEAR 
39N123W. STRONG PRESSURE GRADIENT DEVELOPS AS A RESULT ALONG THE 
COAST OF CALIFORNIA WITH NEAR-GALES EXPECTED TUE. SEAS GENERATED 
BY THE HIGHER WINDS SHOULD REACH NE PORTION OF FORECAST AREA WED.

GAP WINDS...
EARLY SEASON GALE FORCE WIND EVENT CONTINUES IN AND DOWNSTREAM 
OF THE GULF OF TEHUANTEPEC. IXTEPEC MEXICO JUST TO THE WEST OF 
THE GULF OF TEHUANTEPEC HAS BEEN REPORTING N WINDS OF 25 KT PAST 
6-12 HOURS. MAX WINDS IN THE GULF OF TEHUANTEPEC ARE EXPECTED TO 
REMAIN 30 TO 35 KT THROUGH THU WITH DIURNAL VARIABILITY LIKELY.

$$
MUNDELL