000
AXPZ20 KNHC 132145
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 13 2010

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 03N78W TO 04N104W TO 05N113W TO 06N127W TO 
07N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION WAS 
NOTED WITHIN 120 NM EITHER SIDE OF THE AXIS W OF 130W.

...DISCUSSION...
A BROAD MID TO UPPER LEVEL RIDGE EXTENDS FROM AN UPPER 
ANTICYCLONIC CIRCULATION CENTERED NEAR 15N135W TO 34N132W. A 120 
TO 130 KT JETSTREAM ENTERS THE DISCUSSION AREA NEAR 32N130W TO 
27N118W...WHERE UPPER LEVEL WINDS DECREASE TO THE 95 TO 105 KT 
RANGE. THE JET THEN CONTINUES TO THE E INTO WESTERN MEXICO NEAR
20N105W. STRONG SUBSIDENCE WITH A VERY DRY AND STABLE AIR MASS 
EXISTS ACROSS THE AREA N OF THE ITCZ AND W OF 110W. ANOTHER MID
TO UPPER LEVEL TROUGH AXIS EXTENDS FROM THE ITCZ NEAR 06N119W TO 
SW MEXICO NEAR 17N100W AND INTO THE W GULF OF MEXICO. ABUNDANT 
MAINLY MID LEVEL MOISTURE IS BEING ADVECTED FROM THE ITCZ UP 
ALONG/JUST AHEAD OF THE TROUGH AXIS INTO THE SOUTHERN GULF OF 
MEXICO.

AT THE SURFACE...A DISSIPATING COLD FRONT EXTENDS FROM 33N118W 
TO 29N124W TO 27N131W. BROKEN TO OVERCAST LOW CLOUDS ARE WITHIN 
180 NM S AND SE OF THE FRONT. A 1025 MB SURFACE HIGH IS CENTERED 
JUST N OF THE AREA NEAR 32N129W WITH AN ELONGATED RIDGE 
EXTENDING FROM THE HIGH TO JUST W OF THE AREA NEAR 23N145W. THE 
TIGHT PRES GRADIENT INDUCED BY THIS RIDGE IS PRODUCING 20 TO 25 
KT NE TO E TRADES ALONG THE SOUTHERN PERIPHERY. THE NEXT COLD 
FRONT IS APPROACHING 140W FROM THE W...AND SOUTHERLY WINDS AHEAD 
OF THIS TROUGH WILL BEGIN TO INCREASE TO 20 TO 25 KT N OF 25N W 
OF 133W DURING THE NEXT 48 HOURS.

THREE WEAK SURFACE TROUGHS ARE EMBEDDED IN THE ITCZ. THE EASTERN 
MOST TROUGH EXTENDS FROM 08N107W TO 02N107W. SCATTERED SHOWERS 
ARE PRESENT WITHIN 100 NM E OF THE TROUGH AXIS. TO THE W... 
ANOTHER TROUGH EXTENDS FROM 08N114W TO 02N114W WITH NO VISIBLE 
CONVECTION PRESENT. A THIRD TROUGH IS TO THE W FROM 08N128W TO 
03N128W. NO SIGNIFICANT WEATHER WAS NOTED WITH THIS FEATURE.

A TIGHT PRES GRADIENT WILL BECOME ESTABLISHED ALONG THE BAJA 
PENINSULA DURING THE NEXT 48 HOURS...AND AS A RESULT NORTHERLY
WINDS IN THE 20 TO 30 KT RANGE WILL BE PRESENT IN THE GULF OF 
CALIFORNIA N OF 26N AND ALSO N OF 24N W OF THE BAJA PENINSULA TO 
117W.

...GAP WINDS...
GALE FORCE WINDS CONTINUE TO BLOW THROUGH THE GULF OF 
TEHUANTEPEC BUT ARE EXPECTED TO DIMINISH TO LESS THAN GALE FORCE 
WITHIN THE NEXT 12 HOURS.

GALE FORCE WINDS ARE ALSO BLOWING IN THE GULF OF PAPAGAYO. WINDS 
ARE ALSO EXPECTED TO DECREASE TO BELOW GALE FORCE WITHIN THE 
NEXT 12 HOURS.

STRONG NORTHERLY WINDS OF 20 TO 25 KT CONTINUE IN THE GULF OF 
PANAMA WITH THE REMNANTS OF THE FRONTAL TROUGH IN PLACE OVER 
WESTERN PANAMA. WINDS AREA EXPECTED TO DECREASE TO LESS THAN 20 
KT BY THU.

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

$$
LEWITSKY