000
AXPZ20 KNHC 111533
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON JAN 11 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1400 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE LIES ALONG A LINE FROM 02N78W TO 
04N86W TO 03N97W TO 07N115W TO 07N140W. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION CAN BE FOUND WITHIN 150 NM N AND 90 NM S 
OF THE ITCZ AXIS E OF 82W. SCATTERED MODERATE CONVECTION LIES WITHIN 
150 NM N OF THE ITCZ AXIS BETWEEN 90W AND 96W.

...DISCUSSION...
AN UPPER TROUGH EXTENDS SW FROM A LOW OVER ARIZONA THROUGH BAJA 
CALIFORNIA TO 10N120W. A SOUTHWESTERLY UPPER JET ON THE LEADING EDGE 
OF THIS TROUGH IS TRANSPORTING MOISTURE PRIMARILY IN THE FORM OF 
CIRRUS NORTHEASTWARD INTO CENTRAL MEXICO. SOME HIGHLY ISOLATED 
MODERATE CONVECTION CAN BE FOUND IN THE REGION WHERE THE REAR RIGHT 
QUADRANT OF THIS JET INTERSECTS THE ITCZ. A SURFACE TROUGH IS 
EMBEDDED IN THE ITCZ THERE FROM 10N113W TO 04N115W. THE UPPER LEVEL 
TROUGH IS PROGRESSIVE AS IT IS BEING PUSHED EASTWARD BY A STRONG 
ZONAL JET STRETCHED FROM ITS WESTERN EDGE ACROSS THE CENTRAL PACIFIC 
ALONG 33N. THIS JET LIES ON THE SOUTHERN SIDE OF A DEEP LAYER LOW 
CENTERED NEAR 50N150W. A SERIES OF SHORTWAVE SYSTEMS ARE RIDING THE 
JET S OF THE LOW...WITH ONE CURRENTLY BRINGING A COLD FRONT TO THE 
EDGE OF NW WATERS. THE 0606 UTC ASCAT PASS SHOWS SW WINDS JUST BELOW 
GALE FORCE AHEAD OF THE FRONT. NW SWELL ASSOCIATED WITH THE DEEP 
LAYER LOW HAS ALREADY BROUGHT SIGNIFICANT WAVE HEIGHTS OF 20 FT TO 
NW WATERS. THE COLD FRONT IS EXPECTED TO DISSIPATE TUE AS THE CORE 
OF THE SYSTEM LIFTS NORTHEASTWARD OVER THE DEEP LAYER RIDGE ALONG 
THE SOUTHERN CA AND MEXICAN BAJA COASTS. THE 1020 MB SURFACE HIGH 
CURRENTLY NEAR 31N123W WILL HOLD ITS GROUND AS THE COLD FRONT 
DISSIPATES...ALLOWING IT TO MERGE WITH THE HIGH PRES BEHIND THE COLD 
FRONT BY WED. WINDS WILL WEAKEN TO 20 KT BY MON MORNING AS THE FRONT 
DISSIPATES. THE PRES GRADIENT BETWEEN THE HIGH AND THE ITCZ HAS 
INDUCED AN AREA OF TRADES W OF 120W BETWEEN 05N AND 13N ACCORDING TO 
THE 0600 UTC ASCAT PASS. THESE TRADES WILL CONTINUE THROUGH THE 
PERIOD. IN ADDITION...NW SWELL FROM THE COLD FRONT THAT DISSIPATED 
OVER NW WATERS SAT HAS MOVED THROUGH MUCH OF THE FORECAST AREA W OF 
110W.

FARTHER E...AN UPPER RIDGE AXIS EXTENDING FROM AN ANTICYCLONE OVER 
NORTHERN VENEZUELA TO JUST SOUTH OF GALAPAGOS ISLANDS INTERSECTS THE 
ITCZ NEAR THE COAST OF COLOMBIA. THE STRONGEST CONVECTION OVER THE 
FORECAST AREA THIS MORNING LIES HERE AS A RESULT. MOISTURE IS POOLED 
HERE BETWEEN THE STATIONARY FRONT THROUGH COSTA RICA AND 
THE ITCZ WITH SATELLITE PRECIPITABLE WATERS VALUES IN THE 2.0 TO 2.5 
INCH RANGE. CONDITIONS ALOFT SHOULD REMAIN RELATIVELY UNCHANGED THE 
NEXT TWO DAYS...BUT THE POOL OF LOW TO MID LEVEL MOISTURE WILL ERODE 
AS THE BOUNDARY DISSIPATES TO THE NORTH. EXPECT THE CHANCE OF 
CONVECTION TO DECREASE TUE AND WED AS A RESULT.


GAP WINDS...
GULF OF TEHUANTEPEC...THE 0420 UTC ASCAT PASS SHOWS GALE FORCE WINDS 
UP TO 240 NM DOWNWIND OF TEHUANTEPEC. SHIP C6FY8 REPORTED 40 KT 
WINDS NEAR 12.5N96.5W AT 1100 UTC WITH 17 FT SEAS. A STORM WARNING 
CONTINUES TO BE IN EFFECT THROUGH TUE MORNING...BUT GALES ARE 
EXPECTED TO CONTINUE THROUGH THE FORECAST PERIOD AS THE HIGH PRES 
OVER EASTERN MEXICO WILL BE SLOW TO ERODE.

GULFS OF PAPAGAYO AND FONSECA...THE STRONG COLD FRONT THAT BROUGHT 
STORM FORCE CONDITIONS TO TEHUANTEPEC MOVED THROUGH THE GULF OF 
PAPAGAYO SUN AND BROUGHT GALE FORCE WINDS TO THE AREA THAT ARE NOT 
EXPECTED TO DIMINISH DURING THIS FORECAST PERIOD. THE 0238 UTC ASCAT 
PASS BARELY CLIPPED THE AREA AND SHOWED WINDS JUST BELOW GALE 
FORCE...BUT SHIP 9HJB9 REPORTED 45 KT WINDS IN THIS AREA AT 1100 AND 
1200 UTC. THUS...THE GALE IS SET TO 45 KT. WINDS HAVE ALSO RISEN TO 
20 TO 30 KT IN THE GULF OF FONSECA. WINDS WILL TURN MORE EASTERLY BY 
TUE AFTERNOON...TAKING THE WINDS DOWN TO 20 KT IN THE GULF OF 
FONSECA.

GULF OF PANAMA...20 TO 25 KT N WINDS ACROSS PANAMA ARE SPILLING INTO 
THE GULF OF PANAMA N OF 05N. THESE WINDS ARE EXPECTED TO CONTINUE 
OVER THE NEXT 48 HOURS AS THE PRES GRADIENT REMAINS STRONG BETWEEN 
THE CLIMATOLOGICAL LOW PRES OVER NE COLOMBIA AND THE HIGH PRES N OF 
THE COLD FRONT OVER COSTA RICA AND THE SW CARIBBEAN. IN 
ADDITION...SW SWELL IS EXPECTED TO MOVE INTO THIS REGION ON 
WED...EXPANDING THE AREA OF SEAS OVER 8 FT FARTHER W TO ABOUT 86W.

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

$$
SCHAUER