000
AXPZ20 KNHC 262223 CCA
TWDEP 

TROPICAL WEATHER DISCUSSION...CORRECTED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON OCT 26 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2215 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 8N79W TO 
10N90W TO 12N103W TO 12N117W TO 7N130W TO 9N140W. SCATTERED
MODERATE TO STRONG CONVECTION WAS WITHIN 60 NM OF THE AXIS 
BETWEEN 123W-127W...W OF 135W AND WITHIN 120 NM S OF THE AXIS 
BETWEEN 119W-122W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION 
WAS WITHIN 120 NM S OF THE AXIS BETWEEN 101W-105W...AND WITHIN 
60 NM S OF THE AXIS BETWEEN 95W-98W. SCATTERED MODERATE 
CONVECTION WAS WITHIN 120 NM N OF THE AXIS BETWEEN 99W-101W.

...DISCUSSION...

A LONGWAVE TROUGH THAT EXTENDED FROM SW TEXAS SW TO ACROSS N 
CENTRAL MEXICO TO ACROSS SOUTHERN BAJA CALIFORNIA...TO 19N117W
...AND TO NEAR 19N126W WILL BE ENERGIZED BY SHORTWAVE ENERGY 
THAT WILL DIVE SE INTO THE BACKSIDE OF THE TROUGH AMPLIFYING 
THE TROUGH OVER THE S CENTRAL U.S. WITHIN THE NEXT 18-24 
HOURS. THE ASSOCIATED SECONDARY SURFACE COLD FRONT WAS N OF THE 
AREA...BUT WILL PUSH SWD AS A RESULT OF THE SHORTWAVE ENERGY
REACHING THE WATERS JUST N OF 30N INCLUDING NORTHERN BAJA 
LATE TONIGHT INTO TUE MORNING WHERE IT WILL BECOME DIFFUSE. THE 
COMBINATION OF SURFACE BROAD LOW PRES DEEPENING OVER THE 
SOUTHERN GREAT PLAINS AND HIGH PRES BUILDING SE OVER THE WATERS 
ALONG THE U.S. W COAST HAS BROUGHT AND INCREASE OF NW WINDS TO 
THE FAR NORTHERN GULF OF CALIFORNIA SOONER THAN EARLIER 
ANTICIPATED. NW WINDS TO 20 KT WERE NOTED IN A MORNING
QUIKSCAT PASS ACROSS THE GULF N OF ABOUT 27N. AS THE AREA OF 
LOW PRES BEGINS TO MOVE OFF THE NE AND HIGH PRES CENTERED N OF
THE AREA INTENSIFIES AS IT BEGINS TO MOVE S...EXPECT THE 20 KT 
WINDS TO BECOMING S TO SW IN DIRECTION IN ABOUT 24 HOURS...THEN 
W TO NW IN 48 HOURS. THESE WINDS MAY BRIEFLY REACH UP TO 25 KT. 

TO THE SE OF THE LONGWAVE TROUGH...A JET STREAM BRANCH EXTENDED
FROM 12N126W TO 16N115W TO ACROSS MEXICO AT 21N105W...AND 
CONTINUED NE TO THE FAR NW GULF OF MEXICO. MAXIMUM WINDS OF 
60-90 KT AS NOTED IN SATELLITE DERIVED WINDS WERE NEAR THE JET 
CORE. THE JET WAS ADVECTING UPPER LEVEL MOISTURE IN THE FORM OF 
BROKEN CIRRUS CLOUDS ENE ACROSS CENTRAL MEXICO WITHIN ABOUT 300 
NM TO ITS S. DIVERGENT FLOW ALOFT TO THE SE OF THE LONGWAVE 
TROUGH IN COMBINATION WITH LOW LEVEL CONVERGENCE ALONG THE ITCZ 
WAS ALLOW FOR CLUSTERS OF TSTMS TO CONTINUE TO FLARE UP ALONG AND
NEAR THE ITCZ E OF 110W THROUGH THE NEXT 48 HOURS. THE LATEST 
RUNS OF THE GLOBAL MODELS WITH THE BOTH THE GFS AND EUROPEAN MEAN
ENSEMBLES AGAIN SUGGESTED THAT A GYRE OF LOW TO MID LEVEL 
VORTICITY IN THE AREA BETWEEN 95W AND 105W MAY COMBINE TO FORM A 
MORE DEFINITIVE LOW THAT TRACKS IN A NE FASHION LATER ON THE 
WEEK. WILL HAVE TO LOOK OVER A FEW MORE MODEL RUNS TO OBTAIN A 
BETTER DETERMINATION OF TIMING AND INTENSITY OF THIS PROBABLE 
LOW PRES SYSTEM. 

A MID/UPPER LEVEL ANTICYCLONE MOVING E IS OVER SE MEXICO NEAR
17N92W WITH AN RIDGE SW TO 10N99W TO 5N107W. SW FLOW TO THE
NW OF THE ANTICYCLONE WAS ADDING ADDITIONAL MOMENTUM TO FLOW
ASSOCIATED WITH THAT ASSOCIATED WITH THE JET STREAM. THE RIDGE
WAS HELPING TO SUPPORT LIFT FOR CONVECTION ALONG AND NEAR THE
ITCZ E OF 110W AS MENTIONED ABOVE.

TO THE W OF THE LONGWAVE TROUGH...HIGH PRES REMAINS WAS IN 
CONTROL THROUGH ALL LEVELS OF THE ATMOSPHERE WITH A MID/UPPER 
LEVEL RIDGE AXIS ALONG 138W EXTENDING TO AN ANTICYLONE NEAR 
12N138W. AT THE SURFACE...A NEARLY STATIONARY 1029 MB HIGH 
CENTER WAS ANALYZED N OF THE AREA NEAR 34N138W WITH A RIDGE SE 
TO 24N126W. HIGH PRES GENERALLY COVERS THE AREA N OF 20N AND W 
OF 120W. THE PRES DIFFERENCE BETWEEN THE RIDGE AND LOW PRES OVER 
THE WESTERN U.S. IS ALLOWING FOR N-NE WINDS OF 20-25 KT N OF 24N 
AND W OF 122 WITH SEAS 8-10 FT. NE TRADE WINDS OF 20 KT WERE 
NOTED ON THE S SIDE OF THE RIDGE AXIS FROM 10N-24N W OF 
130W...AND FROM 9N-18N BETWEEN 118W AND 130W. THE RIDGE IS 
FORECAST TO STRENGTHEN THROUGH THE NEXT 48 HOURS AS THE PARENT 
HIGH TO THE N INTENSIFIES. LONG PERIOD NW-N SWELLS PRODUCING 
SEAS OF UP TO 18 FT AS PER LATEST WAVEWATCH GUIDANCE ARE 
EXPECTED TO FILTER INTO THE FAR NE PORTION OF THE AREA BEGINNING 
LATE TUE NIGHT INTO WED WITH NW-N WINDS THERE INCREASING TO 
20-30 KT AND WITH HIGHER GUSTS ALONG 30N AND GALE FORCE JUST N 
OF 30N.

SCATTERED TO BROKEN STRATOCUMULUS CLOUDS GENERALLY MOVING WSW
WERE SEEN N OF 14N AND W OF 130W INDICATIVE OF A VERY STABLE 
AIR ACROSS THIS AREA AS WAS FURTHER SUPPORTED BY WIDESPREAD 
MODERATE SUBSIDENCE NOTED IN SATELLITE WATER VAPOR IMAGERY W 
AND SW OF THE LONGWAVE TROUGH TO NEAR 13N. SIMILAR STABLE 
CONDITIONS WERE NOTED S OF THE ITCZ. BROKEN STRATOCUMULUS CLOUDS 
ERODING FROM THE E WERE PRESENT FROM 19N TO 27N BETWEEN
118W AND 130W.

$$
AGUIRRE