000
AXPZ20 KNHC 022203
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI DEC 02 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

MONSOON TROUGH AXIS FROM FROM 09N83W TO 07N92W TO LOW PRES NEAR 
07N97W. ITCZ FROM 07N97W TO 06N105W TO 10N125W TO 08N140W. NO 
SIGNIFICANT CONVECTION NOTED.

...DISCUSSION...

A SHARP UPPER TROUGH EXTENDS FROM THE GREAT BASIN ACROSS NRN 
BAJA CALIFORNIA TO A BASE NEAR 21N120W. SHORT WAVE ENERGY HAS 
ROUNDED THE BASE OF THROUGH AND LIFTED OUT TO THE NE THROUGH THE 
SOUTHERN ROCKIES...ALLOWING THE UPPER TROUGH TO STALL IN PLACE 
OVER THE SW CONUS. ANOTHER MORE VIGOROUS SHORTWAVE TROUGH 
CURRENTLY OVER WRN CALIFORNIA IS DROPPING ALONG THE BACKSIDE OF 
THE TROUGH AXIS AND SHOULD REINFORCE THE TROUGH. ASSOCIATED
DISSIPATING STATIONARY FRONT EXTENDS FROM SE ARIZONA TO THE SRN 
PORTION OF BAJA CALIFORNIA.

FOR THE GULF OF CALIFORNIA...LIGHT NW FLOW AT SAN FELIPE OVER 
THE FAR NW GULF IS AN INDICATION OF HOW MUCH THE FRESH NW FLOW 
BEHIND THE FRONT HAS DIMINISHED...ALTHOUGH STRONG WINDS THE 
LOWER ATMOSPHERE OVER THE NORTHERN AND CENTRAL GULF MAY RESULT 
IN STRONG GUSTY WINDS THROUGH THE AFTERNOON.

W OF 125W...SHIP OBSERVATIONS ALONG AN 1856 UTC ASCAT
SCATTEROMETER PASS SHOW FRESH N WINDS OF 20 KT PERSISTING MAINLY 
N OF 25N W OF 120W. THIS FLOW WILL DIMINISH AND VEER MORE NE TO 
E THROUGH 48 HOURS AS HIGH PRES N OF THE AREA WEAKENS SLIGHTLY 
AND DRIFTS SE. THIS WILL ALSO MAINTAIN FRESH NE TRADES BETWEEN 
12N TO 20N W OF 125W. NW AND N SWELL WITH HEIGHTS TO 12 FT WITH 
PERIODS OF 10 TO 12 SECONDS...WITH LONGER PERIOD NW SWELL OF
15 TO 16 SECONDS MOVING SE ACROSS NE PORTION OF THE AREA. 

1010 MB LOW PRES PERSISTS NEAR 07N97W NEAR THE JUNCTURE OF THE 
MONSOON TROUGH/ITCZ. A SHIP OBSERVATION WITH CALL SIGN DFWV2 
NEAR 9N98W AT 18Z ALONG WITH A 1536 UTC ASCAT PASS SHOWED 20 TO 
25 KT WINDS WITHIN 120 NM N OF THE LOW PRES. GLOBAL MODELS 
SUGGEST SOME INCREASE IN SOUTHERLY FLOW INTO THE LOW THROUGH 24 
HOURS. GLOBAL MODELS SUGGEST THE LOW WILL PERSIST AT LEAST 
THROUGH 72 HOURS AS IT SHIFTS W AROUND 10 KT. THIS IS PLAUSIBLE 
THROUGH 48 HOURS GIVEN THAT THE LOW WILL MOVE INTO INTO THE 
FAVORABLE SE PORTION OF A BROAD UPPER TROUGH ALONG 115W. THE 
UPPER TROUGH AMPLIFIES BEYOND THAT...WITH THE LOW LIKELY 
WEAKENING. A LACK OF DEEP LAYER MOISTURE IS PREVENTING ANY MAJOR 
CONVECTIVE DEVELOPMENT NEAR THIS LOW PRES AREA.

GULF OF TEHUANTEPEC...A 1534 UTC ASCAT SCATTEROMETER PASS SHOWED 
N TO NE WINDS OF 20-25 KT WITH HIGHER GUSTS. THESE WINDS ARE 
FORECAST BY ALL THE GLOBAL MODELS TO CONTINUE THROUGH ANOTHER 24 
HOURS BEFORE DIMINISHING TO LESS THAN 20 KT BY 48 HOURS.

GULF OF PAPAGAYO...OVERNIGHT DRAINAGE FLOW WILL ENHANCE TO N-NE 
FLOW CURRENTLY PREVAILING ACROSS THE WRN CARIBBEAN. FRESH TO 
STRONG NORTHEASTERLY GAP WINDS ARE EXPECTED DURING THE NEXT 
COUPLE OF DAYS...WITH WINDS LIKELY STRONGEST DURING THE LATE 
NIGHT AND EARLY MORNING HOURS. 

$$
COBB