000
AXPZ20 KNHC 141527
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE DEC 14 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...

INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 06N78W TO 05N100W 
TO 08N120W TO 06N127W TO 08N140W. SCATTERED MODERATE CONVECTION 
LIES WITHIN 75 NM EITHER SIDE OF THE ITCZ AXIS W OF 139W. THERE 
IS A 1010 MB LOW PRES SYSTEM EMBEDDED IN THE ITCZ NEAR 08N121W 
THAT HAS SCATTERED MODERATE CONVECTION WITHIN 120 NM OF ITS E 
QUADRANT.

...DISCUSSION...

A WEAKENING 1021 MB SURFACE HIGH LOCATED NEAR 27N138W EXTENDS A 
RIDGE OVER THE FORECAST WATERS N OF 15N AND W OF 115W. THIS 
RIDGE IS INTERRUPTED BY A WEAK TROUGH...A SURFACE REFLECTION OF 
A CUT-OFF LOW ALOFT SITUATED NEAR 17N130W. ONLY A SMALL AREA OF 
FRESH TO STRONG NE TO E TRADEWINDS EXISTS ON THE SOUTHERN 
PERIPHERY OF THE RIDGE OVER FAR WEST WATERS BETWEEN THE ITCZ AND 
15N. SHIP NWS0009 REPORTED 22 KT NEAR 12N137W AT 1200 UTC IN 
THIS AREA. THE SURFACE HIGH WILL WEAKEN TODAY THROUGH WED AS A 
NEW LOW PRES SYSTEM APPROACHES THE NW CORNER OF THE AREA BY THU. 
A NEW BATCH OF NW SWELL WILL SPREAD ACROSS THE NW CORNER OF THE 
DISCUSSION AREA AHEAD OF THE NEXT LOW...BUT SEAS ARE EXPECTED TO 
REMAIN BELOW 8 FT. SW WINDS AHEAD OF THE NEXT SYSTEM ARE 
EXPECTED TO INCREASE TO 20 KT THU MORNING OVER THE FAR NW 
PORTION OF THE FORECAST AREA.

THE AFOREMENTIONED LOW PRES SYSTEM EMBEDDED IN THE ITCZ IS 
EXPECTED TO SLOWLY TRAVEL W AS A TROUGH OVER THE NEXT FEW DAYS 
WITH WINDS TO 20 KT AND AN AREA OF SCATTERED CONVECTION TRACKING 
WITH IT.

ELSEWHERE...WINDS AND SEAS ACROSS MOST OF THE EASTERN NORTH 
PACIFIC FORECAST WATERS WILL BE RELATIVELY TRANQUIL THE 
NEXT FEW DAYS...WITH THE EXCEPTION OF THE LOCATIONS IMPACTED BY 
GAP WINDS. SHORT PERIOD SWELLS OUT OF THE NE GENERATED FROM THE 
GAP AREAS OF TEHUANTEPEC AND PAPAGAYO WILL MERGE BY WED AND 
SPREAD SW AFFECTING MAINLY THE WATERS FROM 05N TO 13N BETWEEN 
89W AND 105W WITH SEAS OF 8 TO 11 FT. WINDS IN THE GAPS WILL 
DIMINISH LATE WED INTO THU AND THESE SHORT PERIOD SWELLS WILL 
QUICKLY SUBSIDE THU MORNING.

GAP WINDS...
THERE HAVE NOT BEEN ANY NEW OBSERVATIONS IN THE GULF OF 
TEHUANTEPEC SINCE A HIGH RESOLUTION ASCAT PASS FROM AROUND 0300 
UTC CLIPPED THE AREA AND SHOWED SEVERAL WIND BARBS OF 30 TO 35 
KT ON THE WEST EDGE OF THE PASS. A GALE WARNING REMAINS IN 
EFFECT FOR THIS AREA UNTIL 14/1800 UTC. WINDS WILL DIMINISH 
BELOW 20 KT BY WED AFTERNOON. 

FRESH NE WINDS WILL CONTINUE IN THE GULF OF FONSECA THROUGH WED 
MORNING WHILE STRONG NE TO E WINDS ARE EXPECTED TO EXPAND 
DOWNWIND OF THE GULF OF PAPAGAYO THROUGH WED BEFORE DIMINISHING 
THU. THE ASCAT PASS NEAR 0300 UTC CONFIRMED 20 KT WINDS NEAR THE 
GULF OF FONSECA...BUT THERE ARE NO NEW OBSERVATIONS DOWNWIND OF 
PAPAGAYO OR FONSECA SINCE THAT TIME.

THE SAME ASCAT PASS ALSO INDICATED NE WINDS OF 20 KT FUNNELING 
INTO THE GULF OF PANAMA AS THE WIND SURGE FROM THE COLD FRONT IN 
THE WESTERN CARIBBEAN MOVED FURTHER SOUTH. MORE RECENT 
OBSERVATIONS FROM SHIP ZCDG4 AT 0700 AND 0800 SHOWED WINDS 
CLOSER TO 30 KT NEAR THE PACIFIC APPROACH TO THE PANAMA CANAL 
AND SHIP ZCDN9 NEAR 07N81W REPORTED 22 KT WINDS AT 1300 UTC...SO 
THE WIND FIELD HAS STRENGTHENED AND EXPANDED NEAR THE GULF OF 
PANAMA SINCE THE ASCAT PASS AROUND 0300 UTC. WINDS ARE EXPECTED 
TO REMAIN JUST BELOW GALE FORCE HERE THROUGH WED MORNING AND 
THEN DIMINISH TO 20 KT BY THU MORNING WITH SUBSIDING SEAS.

$$
SCHAUER/GR