000
AXPZ20 KNHC 292136
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAR 29 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 
2000 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE WAS ANALYZED ALONG 02N78W TO 
05N90W TO 04N105W TO 05N120W TO 05N140W. SCATTERED MODERATE 
CONVECTION WAS WITHIN 150 NM S AND 75 NM N OF THE ITCZ AXIS 
BETWEEN 109W AND 112W. TWO TROUGHS WERE EMBEDDED IN THE ITCZ. 
THE EASTERN TROUGH WAS FROM 09N96W TO 01N97W AND HAD SCATTERED 
MODERATE CONVECTION WITHIN 300 NM EITHER SIDE OF IT S OF 07N. 
THE WESTERN TROUGH WAS FROM 09N115W TO 03N129W AND HAD SCATTERED 
MODERATE CONVECTION WITHIN 150 NM EITHER SIDE OF TROUGH W OF 
117W.

...DISCUSSION...

SUBTROPICS...
A NEW COLD FRONT CURRENTLY FOUND JUST NW OF THE AREA WILL 
DISSIPATE BEFORE REACHING FORECAST WATERS TUE...BUT WILL BRING A 
NEW BATCH OF NW SWELL WITH SIGNIFICANT WAVE HEIGHTS TO 18 FT AND 
WAVE PERIODS REACHING 17-18 SECOND AS THE SWELL PROPAGATES SE. 
THE PRES GRADIENT BETWEEN THE ITCZ AND 1031 MB HIGH PRES BEHIND 
THE COLD FRONT NEAR 32N161W WITH A RIDGE EXTENDING 
EAST-SOUTHEASTWARD TO SOCORRO ISLAND IS MAINTAINING A BROAD AREA 
OF FRESH TO STRONG TRADE WINDS GENERALLY FROM 07N TO 23N W OF 
130W. THIS HIGH PRES CENTER WILL SHIFT E ABOUT 5-10 DEGREES OVER 
THE NEXT TWO DAYS AND MAINTAIN ITS STRENGTH. THE AREA OF FRESH 
TO STRONG TRADE WINDS WILL CREEP NORTHWARD...BUT OTHERWISE 
REMAIN UNCHANGED. THE PRES GRADIENT BETWEEN THE EASTERN EDGE OF 
THE SURFACE RIDGE AND A LEE SIDE TROUGH ALONG THE W SLOPES OF 
THE SIERRA MADRE OCCIDENTAL CONTINUES TO GENERATE NW TO N WINDS 
TO 20 KT IN THE CENTRAL GULF OF CALIFORNIA ACCORDING TO THE 1656 
ASCAT PASS AND IS BELIEVED TO BE GENERATING SIMILAR CONDITIONS 
ALONG THE W COAST OF BAJA CALIFORNIA. WINDS IN THE GULF OF 
CALIFORNIA WILL DIMINISH BELOW 20 KT BY TUE MORNING AS THE 
EASTERN EDGE OF THE RIDGE IS WEAKENED BY THE COLD FRONT N OF THE 
AREA. WINDS WILL ALSO DIMINISH ALONG THE WEST COAST OF NORTHERN 
BAJA CALIFORNIA ABOUT A DAY LATER.

TROPICS...
AN UPPER LOW LIES NEAR 01S124W AND AN ANTICYCLONE LIES TO ITS N 
NEAR 09N123W. A SURFACE TROUGH REFLECTION OF THE LOW ALOFT IS 
EMBEDDED IN THE ITCZ FROM 09N115W TO 03N129W. CONVECTION NEAR 
THE TROUGH IS GENERALLY FOCUSED ON EITHER END WITH DIMINISHED 
CONVECTION ALONG THE CENTER OF THE SURFACE TROUGH WHERE THE FLOW 
ALOFT IS CONFLUENT ALOFT. TO THE SE OF THE UPPER LOW LIES A 
40-50 KT SOUTHWESTERLY UPPER JET WITH THE LEFT EXIT REGION 
DIFFLUENCE SUPPORTING CONVECTION N OF THE ITCZ BETWEEN 109W AND 
112W. FARTHER E...UPPER LEVEL DIFFLUENCE ASSOCIATED WITH A RIDGE 
AXIS THAT PASSES OVER ANOTHER SURFACE TROUGH EMBEDDED IN THE 
ITCZ ALONG 96W/97W IS SPARKING CONVECTION WITHIN 300 NM OF THE 
SURFACE TROUGH.

GAP WINDS...
WHILE THE 1520 UTC AND 1658 UTC ASCAT PASSES MISSED THE GULF OF 
TEHUANTEPEC...THE VISIBLE SATELLITE IMAGERY SHOWS THE TELL-TALE 
ROPE CLOUD ON THE EDGE OF THE ENHANCED GAP WIND REGION. WINDS IN 
THE GULF OF TEHUANTEPEC ARE BELIEVED TO BE AS STRONG AS 45 KT AT 
THE MOMENT...BUT THEY WILL DIMINISH BELOW GALE FORCE BY TUE 
AFTERNOON. THIS SAME COLD FRONT WILL ALSO BRING 20 KT WINDS 
THROUGH THE GULF OF FONSECA ON EARLY TUE THAT WILL DIMINISH IN 
THE AFTERNOON. 

SHIP DHEE NEAR 10N88W AT 1800 UTC REPORTED 22 KT NE WINDS 
DOWNWIND OF THE GULF OF PAPAGAYO. STATION MRLB AT LIBERIA COSTA 
RICA HAS SEEN THEIR WINDS INCREASE FROM 9 KT TO 18 KT OVER THE 
LAST 4 HOURS. WHILE THE MODELS DO NOT SHOW THE WINDS INCREASING 
HERE UNTIL THE FRONT REACHES THE AREA OVERNIGHT...THERE IS 
EVIDENCE THAT THE WINDS HAVE ALREADY BEGUN TO FUNNEL THROUGH THE 
GULF OF PAPAGAYO AND HAVE REACHED 20 KT. WINDS HERE WILL 
INCREASE OVERNIGHT AS THE FRONT PASSES THROUGH AND WILL SPREAD 
DOWNSTREAM TO 93W OVER THE NEXT FEW DAYS.

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

$$
SCHAUER