000
AXPZ20 KNHC 081552
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI OCT 08 2010

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 
1430 UTC.

...THE ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ANALYZED FROM 10N84W TO 
06N97W TO 1010 MB LOW PRES AT 09N110W TO 1009 MB LOW PRES AT 
10.5N120W TO 09N125W TO 1009 MB LOW PRES AT 09N138W CONTINUING W 
BEYOND 09N140W. ISOLATED TO SCATTERED MODERATE CONVECTION WAS 
NOTED WITHIN 150 NM E SEMICIRCLE OF THE LOW PRES CENTERS AT 
09N110W AND 10.5N120W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WAS NOTED WITHIN 120 NM AND 90 NM S OF AXIS W OF 
121W. 

...DISCUSSION...

A SERIES OF UPPER TROUGHS ARE SWEEPING E ACROSS THE SUBTROPICAL 
PORTION OF THE DISCUSSION AREA. THE WESTERNMOST TROUGH EXTENDS 
FROM 35N126W TO 22N140W AND BEYOND...AND IS ACCOMPANIED BY UPPER 
MOISTURE TO THE W OF THE TROUGH AXIS N OF 25N. THE ASSOCIATED 
SURFACE COLD FRONT LAGS BEHIND WELL NW OF THE AREA. A SECOND 
UPPER TROUGH EXTENDS FROM THE DESERT SW OF THE U.S. SW ACROSS 
NRN BAJA CALIFORNIA. A THIRD UPPER TROUGH EXTENDS FROM THE ERN 
GULF OF MEXICO SW THROUGH SRN MEXICO AND ACROSS THE ISTHMUS OF 
TEHUANTEPEC AND OVER THE TROPICAL E PACIFIC TO A WEAK UPPER 
CYCLONE NEAR 11N103W. AN UPPER ANTICYCLONE IS CENTERED JUST NW 
OF THIS TROUGH AXIS NEAR 15N107W...WITH RIDGING W TO NEAR 
15N125W AND N-NE ACROSS MEXICO TO SW TEXAS. W TO SW UPPER LEVEL 
FLOW DOMINATES THE AREA TO THE W AND NW OF THE UPPER RIDGE...AND 
SE OF THE FIRST UPPER TROUGH. A SHARP AND NEGATIVELY TILTED 
UPPER LEVEL TROUGH UNDERCUT THE RIDGE...EXTENDING FROM 14N129W 
SE TO THE GALAPAGOS ISLANDS. THIS TROUGH CROSSED THE ITCZ 
BETWEEN 115W AND 130W AND WAS AIDING IN VENTILATING MODEST ITCZ 
CONVECTION THERE. UPPER LEVEL RIDGING ACROSS THE FAR W CARIBBEAN 
EXTENDED SW INTO THE TROPICAL EPAC E OF 95W...BUT WAS SOMEWHAT 
CONFLUENT YIELDING MODERATELY STABLE CONDITIONS ALOFT.  

AT THE LOW LEVELS...HIGH PRES IS CENTERED NEAR 31N128W 1024 MB 
WITH A RIDGE SW TO JUST N OF THE HAWAIIAN ISLANDS AND SE TO 
18N108W. MODERATE TO FRESH NE TO E TRADES WERE FOUND S OF THE 
RIDGE FROM 22N TO THE ITCZ W OF 110W...WITH A FEW CYCLONIC 
SWIRLS NOTED ABOVE WITHIN THE ITCZ. SEAS ACROSS THIS AREA WERE 
GENERALLY RUNNING 8 TO 11 FT. LITTLE CHANGE IS ANTICIPATED IN 
THIS SYNOPTIC SCENARIO IN THE NEXT 48 HOURS AS THESE WEAK LOWS 
MOVES W AT 10 KT. EXPECT HIGHEST WINDS TO 25 KT AND SEAS 10 TO 
11 FT TO REMAIN N OF THE SERIES OF LOWS BETWEEN 118W AND 128W. 

E OF THIS AREA...POST FRONTAL...NORTHERLY GAP WIND FLOW THROUGH 
THE GULF OF TEHUANTEPEC HAS DIMINISHED TO 20 TO 30 KT OVER THE 
PAST FEW DAYS...WHICH IS THEN FLOWING SW TO W AND DOWNSTREAM TO 
S OF 14N AND W TO 110W...AND MAINTAINING A STABLE ENVIRONMENT. 
EXPECT THESE WINDS TO GRADUALLY DIMINISH TO 20 KT SAT NIGHT AND 
TO LESS THAN 20 KT SUN.

BROAD LOW PRES CONTINUES OVER THE W TWO-THIRDS OF THE CARIBBEAN. 
GLOBAL MODELS HAVE HINTED AT THE DEVELOPMENT OF A MODEST LOW IN 
THE SW CARIBBEAN OVER THE PAST FEW DAYS. IF THIS OCCURS...EXPECT 
THE S TO SW FLOW FROM THE EPAC ACROSS COSTA RICA AND PANAMA TO 
INCREASE.
  
$$
STRIPLING