East Pacific Tropical Weather Discussion

000
AXPZ20 KNHC 262146
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU NOV 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 
2115 UTC.

...ITCZ...

AXIS ANALYZED ALONG 08N78W TO 06N92W TO 05N95W TO 07N118W TO 
07N121W TO 06N140W. SCATTERED MODERATE AND ISOLATED STRONG 
CONVECTION WAS NOTED WITHIN 90 NM N OF THE AXIS BETWEEN 92W AND 
93W AND ALSO WITHIN 120 NM N OF THE AXIS BETWEEN 115W AND 118W. 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION WAS NOTED 
WITHIN 180 NM N OF THE AXIS W OF 121W AND ALSO WITHIN 90 NM S
OF THE AXIS BETWEEN 121W AND 126W.

...DISCUSSION...

WATER VAPOR SATELLITE IMAGERY INDICATES A LONGWAVE UPPER LEVEL 
TROUGH STRETCHING FROM THE WASHINGTON STATE COAST NEAR 46.5N142W 
TO 33N144W TO 23N160W JUST NW OF KAUAI HAWAII. THIS TROUGH WILL 
CONTINUE TO MOVE EASTWARD PUSHING A SURFACE COLD FRONT INTO THE 
NW PORTION OF THE DISCUSSION AREA THIS EVENING. STRONG HIGH PRES 
OF 1036 MB NEAR 39N147W AT 1800 UTC WILL BUILD IN BEHIND THE 
FRONT OVER THE N WATERS TONIGHT THROUGH THE NEXT FEW DAYS. A 
TIGHT PRES GRADIENT BETWEEN THE HIGH AND LOWER PRES OF THE ITCZ 
WILL RESULT IN NE TRADES IN THE 20 TO 30 KT RANGE. AN EARLIER 
JASON ALTIMETER PASS NW OF 32N140W CAPTURED SEAS UP TO 16 FT AND 
THIS SET OF LARGE NW SWELL IS ALREADY MOVING INTO OUR DOMAIN AND 
WILL CONTINUE TO PROPAGATE THROUGH OUR AREA W OF 110W DURING THE 
NEXT 48 HOURS. 

ANOTHER UPPER LEVEL TROUGH IS LOCATED FROM THE N GULF OF 
CALIFORNIA SW TO NEAR 10N126W WITH VERY DRY AND STABLE AIR IN 
PLACE NW OF THE TROUGH. MOIST SW FLOW ALOFT EXISTS AHEAD OF THIS 
FEATURE RESULTING IN MAINLY MID TO HIGH LEVEL CLOUD COVER WITH 
NO NOTICEABLE IMPACTS ON SENSIBLE WEATHER CONDITIONS AT THE 
SURFACE. 

A 1606 UTC ASCAT PASS INDICATED A WEAK AREA OF LOW PRES NEAR 
06N93W ALTHOUGH CONVECTION ASSOCIATED WITH THIS SYSTEM REMAINS 
CONFINED TO THE NE QUADRANT OF THE LOW DUE TO STRONG S-SW SHEAR 
AND VERY DRY AIR IN PLACE ALOFT. THE LOW IS FORECAST TO CONTINUE 
TO MOVE TO THE W AT 10 KT OVER THE NEXT FEW DAYS AND MODEL 
GUIDANCE INCREASES WINDS TO 20 TO 25 KT AROUND THE LOW BY 48 
HOURS.

...GAP WINDS...
GALE CONDITIONS OCCURRING NOW IN THE GULF OF TEHUANTEPEC AND 
WINDS WILL CONTINUE TO INCREASE THIS EVENING...REACHING STORM 
FORCE (50 KT OR GREATER) BY 0000 UTC. STORM FORCE WINDS THEN 
EXPECTED TO CONTINUE THROUGH 0000 UTC TOMORROW...WITH GALES
FORECAST TO EXIST THEREAFTER THROUGH EARLY SATURDAY.  

EASTERLY TRADES IN THE W CARIBBEAN WILL CONTINUE TO FUNNEL 
THROUGH THE GULF OF PAPAGAYO AND DOWNSTREAM WATERS TO NEAR 88W
FOR THE NEXT FEW DAYS MAINTAINING FRESH TO STRONG WINDS THERE. 

NW TO N WINDS OF 20 TO 25 KT CONTINUE IN THE N GULF OF 
CALIFORNIA N OF 28N DUE TO A TIGHT PRES GRADIENT BETWEEN HIGH 
PRES OVER NE MEXICO...A LOW PRES TROUGH ALONG THE E GULF OF 
CALIFORNIA COAST...AND A HIGH PRES RIDGE W OF THE BAJA PENINSULA.
THE GRADIENT WILL WEAKEN AND WINDS WILL DIMINISH TO LESS THAN 20 
KT WITHIN THE NEXT 6 HOURS.

$$

LEWITSKY