000
AXPZ20 KNHC 141542
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT NOV 14 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 
1515 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 07N78W TO 
08N100W TO 12N114W TO 09N130W TO 10N140W. SCATTERED MODERATE TO 
STRONG WITHIN 120 NM N OF AXIS BETWEEN 105W AND 113W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 120 NM EITHER SIDE OF AXIS W OF 
132W. SCATTERED MODERATE WITHIN 90 NM EITHER SIDE OF AXIS 
BETWEEN 101W AND 105W. 

...DISCUSSION...

SHARPENING MID TO UPPER LEVEL TROUGH IS THE DOMINANT FEATURE 
ALOFT OVER THE AREA. THIS TROUGH EXTENDS FROM A CYCLONIC 
CIRCULATION OVER EXTREME NW BAJA CALIFORNIA SW TO NEAR 20N135W. 
STRONG UPPER LEVEL SUBSIDENCE/DRY AIR ALOFT WAS NOTED IN THE 
WAKE OF THE TROUGH. AXIS OF SUBTROPICAL JET EXTENDED FROM THE 
BASE OF THE TROUGH NE THROUGH CENTRAL BAJA CALIFORNIA TO THE SRN 
GREAT PLAINS OF THE U.S. CORE SPEEDS WITHIN THE JET OF 110 KT 
WAS AIDING IN TRANSPORTING TROPICAL MOISTURE NE INTO A 
DEVELOPING STORM SYSTEM OVER THE SRN GREAT PLAINS. 

AT THE SURFACE...TROUGH EMBEDDED WITHIN THE ITCZ EXTENDED FROM 
13N135W TO 10N140W. SCATTEROMETER DATA CONTINUED TO SHOW A BROAD 
AREA OF 20 TO 25 KT TRADE WINDS GENERALLY FROM 10N TO 25N W OF 
125W ASSOCIATED WITH A TIGHT PRES GRADIENT BETWEEN A 1029 MB 
SURFACE HIGH PRES CENTERED NEAR 35N147W AND THE SURFACE 
TROUGH/ITCZ. THE TRADE WINDS ARE PRODUCING LOCALLY GENERATED 
WIND WAVES AND THIS COUPLED WITH PERSISTENT NORTHERLY SWELL IS 
RESULTING IN COMBINED SEAS IN THE 8 TO 13 FT RANGE. THE PRES 
GRADIENT WILL REMAIN TIGHT AS THE HIGH PRES SYSTEM MOVES TO NEAR 
32N127W BY MON. THE HIGH WILL WEAKEN BY MID WEEK AS A STRONG 
COLD FRONT APPROACHES THE FAR NW CORNER OF THE AREA.

OTHERWISE...FARTHER EAST A 1230 UTC HIGH RESOLUTION QUIKSCAT 
PASS CAPTURED A 1010 MB SURFACE LOW PRES SYSTEM NEAR 08N89W. 
MODEL GUIDANCE SLOWLY MOVES THIS SYSTEM TO THE W WHILE HOLDING 
THE LOW FAIRLY WEAK AND BRINGING IT TO NEAR 06N95W BY EARLY 
MON. VISIBLE SATELLITE IMAGERY OVER THE PAST SEVERAL HOURS SHOWS 
A SMALLS CALE FEATURE EMBEDDED WITHIN THE ITCZ. 

GAP WINDS...
BUILDING HIGH PRESSURE OVER THE GREAT BASIN WILL RESULT IN 
INCREASING NW WINDS IN THE GULF OF CALIFORNIA WITHIN 24 HOURS. 
DIAGNOSTIC TOOLS FROM AN IN-HOUSE STUDY ON THESE EVENTS SUGGEST
THE POTENTIAL FOR NW WINDS TO BRIEFLY REACH GALE FORCE LATE SUN. 
THIS IS NOT REFLECTED IN THE HIGH SEAS AT THIS TIME PENDING THE 
EVALUATION OF THE 12 UTC GUIDANCE. WINDS IN THE HIGH SEAS HAVE 
BEEN BUMPED UP TO 30 KT WITH HIGHER GUSTS. IN ANY EVENT THE 
STRONG NW WINDS WILL THEN GRADUALLY DIMINISH BY MID WEEK AS THE 
HIGH PRES RIDGE TO THE WEST WEAKENS. 

$$
COBB