000
AXPZ20 KNHC 301619 CCA
TWDEP 

TROPICAL WEATHER DISCUSSION...CORRECTED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI OCT 30 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE WAS CENTERED ALONG 9N84W 
11N100W TO 10N110W TO 9N120W TO 7N131W TO 8N140W. SCATTERED
MODERATE TO STRONG CONVECTION WAS WITHIN 120 NM EITHER SIDE
OF THE AXIS BETWEEN 92W-99W. SCATTERED MODERATE CONVECTION
WAS WITHIN 120 NM S OF THE AXIS BETWEEN 111W-113W AND 118W-121W.

...DISCUSSION...

A SHARP DEEP LAYERED TROUGH EXTENDS FROM NW TEXAS TO ACROSS NW
MEXICO...THEN SW TO A COL REGION NEAR 25N12W. THE TROUGH EXTENDS
SW TO AN UPPER LEVEL CYCLONIC MOVING SW NEAR 21N134W. A TROUGH
EXTENDS FROM THE CIRCULATION SW TO W OF THE AREA NEAR 16N140W.
A JET STREAM BRANCH ENTERS THE REGION THROUGH 12N140W...AND 
EXTENDS NE TO NE TO 18N130W...THEN CONTINUES E TO ACROSS CENTRAL 
MEXICO NEAR 21N105W WHERE IT SHARPLY TURNS NE TO ACROSS EASTERN 
TEXAS AND N TO ACROSS HE MID-WEST REGION OF THE U.S. MAXIM JET 
CORE WINDS ARE IN THE RANGE OF 60-90 KT NEAR THE JET CORE. THE 
TROUGH WILL CONTINUE TO SHIFT E THROUGH THE WEEKEND. TO THE W OF 
THE TROUGH...A VERY SHARP AND LARGE UPPER RIDGE WITH ITS CREST 
SPILLING SE IS ROUGHLY ALONG 146W/147W.

UPPER LEVEL CONFLUENCE INTO THE BACKSIDE OF THE TROUGH IS 
RESULTING MODERATE TO STRONG SUBSIDENCE AND VERY STABLE AIR 
ACROSS THIS AREA NW OF THE ABOVE JET STREAM BRANCH. SATELLITE 
IMAGERY SHOWED PATCHES OF BROKEN TO OVERCAST STRATOCUMULUS 
MOVING SW OVER THIS AREA. AT THE SURFACE...A 1026 MB HIGH CENTER 
N OF THE AREA NEAR 35N133W EXTENDS A RIDGE SE TO NEAR 24N121W. 
THE PRES DIFFERENCE BETWEEN THE HIGH AND LOWER PRES TO THE SE
IS RESULTING IN NW-N WINDS OF 20-25 KT THROUGH THE GULF OF 
CALIFORNIA FROM 23N TO 27N. EXPECT THESE WINDS TO SHIFT
TO THE NORTHERN PORTION OF THE GULF IN 24 HOURS...THEN 
DIMINISH TO LESS THAN 20 KT IN 48 HOURS. SLIGHTLY TIGHTER PRES
GRADIENT ON THE SOUTHERN PERIPHERY OF THE RIDGE IS INDUCING
AN AREA OF NE-E TRADES OF 20 KT FROM 15N-24N W OF 117W. THIS
AREA WILL DIMINISH SLIGHTLY OVER THE NEXT 48 HOURS AS THE HIGH
TO THE N WEAKENS SOME...HOWEVER RESIDUAL N TO NE SWELL FROM 
PREVIOUS STRONG N WINDS OVER THE NE PORTION WILL SEND SEAS TO
8 FT S TO NEAR 10N THROUGH SUN.

OVER THE EASTERN PORTION...AN UPPER RIDGE CONTINUES FROM SW 
GULF OF MEXICO SW TO AND UPPER LEVEL ANTICYCLONIC CYCLONIC
CIRCULATION NEAR 8N111W..WHILE A TUTT LOW HAS GRADUALLY 
RETROGRADED FROM THE SW CARIBBEAN TO JUST SW OF HONDURAS.
DIFFLUENCE ALOFT INDUCED BY THIS PATTERN IS MAINTAINING ACTIVE 
CONVECTION ALONG AND NEAR THE ITCZ ACROSS THIS PORTION OF THE 
EPAC...AS THE MONSOONAL GYRE DOMINATES E OF 110W. GLOBAL MODELS 
CONTINUE TO SUGGEST THAT LOW PRES MAY FORM OVER THE AREA S OF 
GUATEMALA AND SE MEXICO. VISIBLE SATELLITE IMAGERY SHOWED A WEAK 
1009 MB LOW NEAR 11N93.5W DRIFTING W.

GAP WINDS...
HIGH PRES BUILDING SE ACROSS SOUTHERN MEXICO IN THE WAKE OF A 
COLD FRONT OVER THE WESTERN GULF OF MEXICO WILL USHER N-NE
WINDS OF 20-30 KT THROUGH THE GULF OF TEHUANTEPEC BEGINNING 
LATE SAT AFTERNOON OR EARLY SAT EVENING...THEN INCREASING TO
GALE FORCE BY DAYBREAK SUN MORNING WITH SEAS BUILDING UP TO
13 FT.

$$
AGUIRRE