000
AXPZ20 KNHC 230349
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT JAN 23 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 
0315 UTC.

...ITCZ...
AXIS ALONG 05N77W TO 05N108W TO 03N111W TO 06N125W TO 06N140W.  
SCATTERED MODERATE CONVECTION WITHIN 120 NM S OF AXIS FROM 82W 
TO 88W.  SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 
NM OF AXIS FROM 100W TO 104W AND W OF 124W.

...DISCUSSION...
BROAD MID TO UPPER LEVEL RIDGE AXIS ALONG 139W ENTERS E PAC 
BRINGING STRONG JET CORE 170 KT OVER ITS CREST.  JET SLIDES 
BETWEEN RIDGE CREST AND NEGATIVELY TILTED TROUGH CENTERED AT 
UPPER LEVEL CYCLONIC VORTEX WELL N OF AREA.  SUCCESSION OF 
SEVERAL SHORT WAVES ERODE RIDGE CREST AS THEY SLIDE AROUND BASE 
OF TROUGH ADVECTING ABUNDANT AMOUNTS OF MOISTURE...AND ATTENDANT 
PRECIPITATION EVENTS.  CREST EROSION ALLOWS SHORT WAVE TO BRING 
MOISTURE FURTHER S THAN PREVIOUSLY EXPECTED...AND FORECAST... 
REACHING AS FAR S AS 25N NEAR BAJA CALIFORNIA.  

SECOND MID TO UPPER LEVEL RIDGE CENTERED PREVIOUSLY OVER ISTHMUS 
OF TEHUANTEPEC YIELDED TO SHORT WAVES AND MOVED OVER YUCATAN 
PENINSULA ALLOWING ABUNDANT MOISTURE TO CROSS INTO NW MEXICO AND 
SW CONUS.      

ELSEWHERE AT THE SURFACE...
COLD FRONT ACROSS NW MEXICO AND SRN THIRD OF BAJA CALIFORNIA NOW 
BRINGS TOUCH OF SEASONAL WEATHER INTO OTHERWISE DRY AREA.  
SECOND COLD FRONT STILL W OF 140W CARRY STRONG SW WINDS AHEAD OF 
BOUNDARY WITHIN 24 HRS...BUT MODEL GUIDANCE MAINTAIN GALE FORCE 
WINDS JUST N OF 30N AS NEGATIVELY TILTED TROUGH IS FORCED NE BY 
RIDGES MENTIONED ABOVE.  AFTER SEEING RIDGES ERODE FROM AREA... 
POSSIBILITY OF GALE FORCE WINDS INTRUDING S OF 30N MAY OCCUR.

SURFACE HIGH PRES CENTER 1013 MB AT 20N109W WEAKENS AS IT IS 
FORCED FURTHER E OVER MEXICO BY COLD FRONT ACROSS BAJA 
CALIFORNIA.  NEW RIDGE WITH 1018 MB HIGH PRES CENTER BUILDS IN 
WAKE OF COLD FRONT AND REINFORCES FRESH TRADES W OF 135W AND 
INTRODUCES STRONG NW WINDS ALONG BOTH COASTS OF BAJA CALIFORNIA. 

LARGE LONG PERIOD NW SWELLS CONTINUE TO CROSS E PAC BASIN AND 
POUND COASTAL AREAS WITH BREAKERS AS HIGH AS 20 FT.  SWELL  
TRAINS EXPECTED TO CONTINUE CROSSING E PAC THROUGH NEXT 48 HRS 
AND BEYOND. 

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

$$
WALLY BARNES