000
AXPZ20 KNHC 090924
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JAN 09 2011

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 05N77W 
TO 07N93W TO 1008 MB LOW NEAR 08N108W TO 05N125W TO 08N140W. NO 
SIGNIFICANT CONVECTION IS NOTED.

...DISCUSSION...

A SURFACE RIDGE DOMINATES THE AREA N OF 15N INCLUDING THE BAJA 
CALIFORNIA PENINSULA. THE 0410 UTC ASCAT PASS SHOWED NW TO N 
WINDS OF 20 KT NEAR THE SOUTHERN BAJA CALIFORNIA PARTICULARLY 
FROM 20N TO 24N BETWEEN 108W AND 114W. SIMILAR WINDS ARE ALSO 
NOTED N OF 24N AND E OF 120W TO THE WESTERN COAST OF THE BAJA 
PENINSULA. WELL TO THE NW OF THE AREA A 1000 MB GALE CENTER IS 
NEAR 31N155W. AHEAD OF IT...A STATIONARY FRONT LIES ABOUT 
240-300 NM W OF THE AREA. THE PRES GRADIENT BETWEEN THIS SYSTEM 
AND THE RIDGE OVER FORECAST WATERS IS AFFECTING THE AREA N OF 
23N W OF 135W WITH SE-S WINDS OF 20-25 KT. THESE WINDS ARE 
EXPECTED TO CONTINUE THROUGH THE NEXT 24 HOURS...THEN DIMINISH 
SOME BY 48 HOURS WITH SEAS OF 8 TO 12 FT IN LARGE NW SWELLS... 
SUBSIDING TO 10 FT BY 48 HOURS. AN AREA OF FRESH TRADE WINDS CAN 
BE FOUND ON THE SOUTHERN PERIPHERY OF THE RIDGE FROM 08N TO 20N 
BETWEEN 115W AND 135W. THE 0548 UTC ASCAT PASS VERIFIED THE 
PRESENCE OF THESE WINDS. THIS WEATHER PATTERN WILL PERSIST OVER 
THE NEXT COUPLE OF DAYS AS THE RIDGE REMAINS IN PLACE BLOCKING 
THE MOVEMENT OF THE FRONT LOCATED W OF AREA . 

A 1008 MB LOW PRES REMAINS EMBEDDED WITHIN THE ITCZ NEAR 8N108W. 
AN ASCAT PASS FROM YESTERDAY REVEALED SE TO S 20 TO 25 KT WINDS 
WITHIN 90 NM OF THE LOW IN THE SE QUADRANT. THE MOST RECENT 
ASCAT PASS...FROM 0406 UTC...SHOWED A WELL DEFINED CYCLONIC 
CIRCULATION WITH WINDS OF 20 KT WITHIN 120 NM SE QUADRANT AND 
150 NM NW QUADRANT OF THE LOW CENTER. IN ADDITION...SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 60 NM OF THIS SYSTEM. THE 
GLOBAL MODELS CONTINUE TO FORECAST THE LOW TO TRACK IN A GENERAL 
WNW DIRECTION OVER THE NEXT 48 HOURS WHILE REMAINING RATHER WEAK.
PRES GRADIENT BETWEEN THE LOW AND THE RIDGE TO ITS N WILL 
PRODUCE AN AREA OF NE TO E WINDS OF 20 KT WITHIN 120 NM N 
SEMICIRCLE OF THE LOW CENTER IN ABOUT 48 HOURS. SATELLITE 
DERIVED WINDS AND ANALYSIS FROM CIMSS ALONG WITH THE LATEST 
WATER VAPOR IMAGERY INDICATE THAT THE UPPER LEVEL ENVIRONMENT 
OVER THIS LOW HAS BECOME RATHER HOSTILE AS UPPER LEVEL WLY WINDS 
CONTINUE TO INCREASE IN SPEEDS.
 
A VERY PRONOUNCED LARGE DEEP LAYER TROUGH IS JUST W OF THE 
REGION AND IS SUPPORTING THE ABOVE MENTIONED GALE CENTER AND 
FRONTAL SYSTEM. A CLUSTER OF SHOWERS AND TSTMS WITH POSSIBLE 
GUSTY WINDS IS NEAR 19N139W.

LONG PERIOD NW SWELL CONTINUES TO PROPAGATE SE ACROSS THE 
REGIONAL WATERS COVERING THE AREA W OF 110W. ANOTHER SET OF NW 
SWELL SHOULD REACH THE FAR NW PORTION BY MON. 

LOOKING AHEAD...A SURGE OF COLD AIR IS EXPECTED TO IMPACT THE 
WESTERN GULF OF MEXICO TUE THROUGH THU...AND COULD DELIVER A 
GALE FORCE WIND EVENT THROUGH THE GULF OF TEHUANTEPEC BY WED.

$$
GR