000
AXPZ20 KNHC 280348
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU JAN 28 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0245 UTC.

...ITCZ...

THE ITCZ AXIS WAS ANALYZED ALONG 04N77W TO 03.5N80W TO 06N88W TO 
03N100W TO 03N108W TO 04N113W TO 05N123W TO 03N140W. ISOLATED 
MODERATE CONVECTION WAS OCCURRING WITHIN 120 NM N OF AXIS 
BETWEEN 86W AND 99W. ISOLATED TO SCATTERED MODERATE CONVECTION 
WAS OCCURRING WITHIN 150 NM N AND 30 NM S OF AXIS BETWEEN 102W 
AND 128W. 

...DISCUSSION...

A MID TO UPPER LEVEL CYCLONE TRACKING E-SE ACROSS NRN BAJA 
CALIFORNIA AND INTO THE FAR N GULF OF CALIFORNIA HAS BEGUN TO 
FILL AND WAS BECOMING ABSORBED WITHIN A SHARP LONG WAVE TROUGH 
EXTENDING FROM THE WRN U.S. S-SE INTO THE NRN GULF OF 
CALIFORNIA...CONTINUING S TO 24N113W THEN SW AS A NARROW 
ELONGATED MID LEVEL TROUGH TO 13N127W. THIS FEATURE WAS MOVING 
THROUGH THE N PORTIONS OF A BROADER UPPER LEVEL TROUGH EXTENDING 
FROM THE FILLING UPPER LOW TO NEAR 06N130W. MULTILAYERED 
MOISTURE CONTINUES TO SPREAD E AND NE ACROSS THE ERN SEMICIRCLE 
OF THE TROUGH/LOW OVER THE AREA N OF 24N ACROSS THE S HALF OF 
BAJA CALIFORNIA...THE NW QUARTER OF MEXICO AND INTO THE DESERT 
SW OF THE U.S. THIS FILLING UPPER LOW HAD AN ASSOCIATED SURFACE 
LOW LOCATED JUST NE ALONG THE ARIZONA-MEXICO BORDER...WITH VERY 
WEAK FRONTAL TROUGH EXTENDING S THROUGH THE NRN GULF AND THEN 
ARCHING SW ACROSS CENTRAL BAJA NEAR 27N AND CONTINUING AS A 
DIFFUSE LOW LEVEL BOUNDARY TO NEAR 22N120W. 
  
BROAD UPPER LEVEL RIDGES SANDWICHED THIS BROAD UPPER TROUGH ON 
EITHER SIDE...BOTH TILTED INWARD TOWARDS THE TROUGH AXIS...AND 
AIDING IN ITS SLOWED E PROGRESSION ACROSS THE FORECAST AREA. 
THE MID TO UPPER LEVEL TROUGH IS FORECAST TO LIFT OUT TO THE NE 
AND OVER THE RIDGE TO ITS EAST OVER THE NEXT FEW DAYS...WHILE 
THE BROAD UPPER TROUGH SLIDES SLOWLY EWD TO ALONG 110W BY FRI 
EVENING. VERY STRONG SUBSIDENCE WAS NOTED UNDER THE WRN RIDGE AT 
THE TAIL END OF THE MID-UPPER TROUGH...WITHIN 6-10 DEGREES OF 
10N141W.

ELSEWHERE AT THE SURFACE...THE COLD FRONT ACROSS BAJA AND THE 
GULF OF CALIFORNIA SHOULD MOVE E OF AREA TONIGHT. WEAKENING HIGH 
PRESSURE NEAR 36N128W EXTENDED S-SW TO 15-20N...PRODUCING NE 
TRADES OF 20 KT FROM 11N TO NEAR 18N W OF 128W...AND A SOLID 25 
KT FROM 11N S TO THE ITCZ W OF 128W. THE ASSOCIATED NE WIND 
SWELL GENERATED BY THESE TRADES WAS MIXING WITH SUBSIDING NW 
SWELLS THAT HAVE BEEN PROPAGATING SE ACROSS THE PACIFIC WATERS. 
THE REMAINING WATERS WELL OFFSHORE OF CENTRAL AMERICA WERE 
DOMINATED BY LIGHT TO MODERATE TRADES LESS THAN 20 KT...AND 
MIXED FADING NW AND SW SWELL. 

GAP WINDS...MINIMAL GALES OCCURRING IN THE GULF OF TEHUANTEPEC 
HAVE DIMINISHED TO 20-30 KT THIS EVENING AND ARE EXPECTED TO 
DIMINISH FURTHER...TO BELOW 20 KT ON THU. NE TO E TRADES OVER 
THE SW CARIBBEAN ARE FUNNELING THROUGH THE GULF OF PAPAGAYO AT 
20 TO 30 KT AND EXPANDING IN A NARROW W-SW PLUME TO 94W...AND 
ARE EXPECTED TO CONTINUE THROUGH FRI. NORTHERLY WINDS SURGING 
THROUGH THE GULF OF PANAMA AT 20 TO 25 KT AND EXPECTED TO 
DIMINISH TO 20 KT OR LESS FRI.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
STRIPLING