000
AXPZ20 KNHC 272128
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN JAN 27 2013

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2000 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS WAS ANALYZED FROM 04N77W TO 02N82W TO 
09N87W TO 06N93W. ITCZ AXIS WAS ANALYZED FROM 06N93W TO 05N107W 
TO 09N127W TO 04N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 
60 NM EITHER SIDE OF THE AXIS BETWEEN 119W AND 123W.

...DISCUSSION...
A POSITIVELY TILTED UPPER-LEVEL TROUGH HAS PUSHED ITS WAY 
INTO THE NORTHERN PORTION OF THE FORECAST AREA. THE NORTHERN 
STREAM UPPER JET ON THE LEADING EDGE OF THIS TROUGH IS EXPECTED 
TO PHASE WITH THE SOUTHERN STREAM JET...CURRENTLY W OF 120W 
CENTERED NEAR 15N...ON MON. THE AMPLIFIED UPPER TROUGH WILL MOVE 
EASTWARD INTO NORTH AMERICA THROUGH TUE. A COLD FRONT ASSOCIATED 
WITH THE UPPER TROUGH WILL PUSH THROUGH NW MEXICO MON AND TUE. 

THE RESULTING MORE AMPLIFIED UPPER PATTERN WILL SET UP A 
STRONGER DEEP-LAYER RIDGE OVER THE FORECAST AREA. THE 
SUBTROPICAL SURFACE HIGH HAS ALREADY INCREASED IN 
STRENGTH...WITH A 1035 MB HIGH ANALYZED NEAR 40N140W. THE 1824 
UTC ASCAT PASS CAPTURED A SMALL AREA OF STRONG E-NE TRADE WINDS 
OVER W WATERS. THE AREA OF STRONG TRADES WILL EXPAND THROUGH THE 
FORECAST PERIOD. 

NW SWELL CONTINUES TO MAKE ITS WAY THROUGH THE MAJORITY OF THE 
FORECAST WATERS...WITH PERIODS AS LONG AS 20 SECONDS. THIS NW 
SWELL WILL MIX WITH INCREASING NE WIND-WAVES GENERATED BY THE 
STRONG TRADE WINDS. SEAS THAT ARE CURRENTLY AS HIGH AS 10 FT IN 
NW SWELL W OF 116W WILL REACH AS HIGH AS 12 FT BY TUE UNDER THE 
STRONG TRADE REGIME. 

GAP WINDS...
GULF OF TEHUANTEPEC...HIGH PRES CENTERED IN THE NE GULF OF 
MEXICO YESTERDAY HAS BECOME ENGULFED IN STRONGER HIGH PRES TO 
THE NE...WEAKENING THE RIDGING IN THE SW GULF OF MEXICO AND 
CUTTING OFF THE STRONG NORTHERLY FLOW THROUGH THE ISTHMUS OF 
TEHUANTEPEC. WINDS AND SEAS ARE BELOW ADVISORY CRITERIA IN THE 
GULF OF TEHUANTEPEC AND ARE EXPECTED TO REMAIN SO THROUGH TUE.

GULF OF PAPAGAYO...STRONG HIGH PRESSURE CENTERED OVER THE MID 
ATLC UNITED STATES IS MAINTAINING MODERATE TO FRESH TRADE WINDS 
ACROSS THE SW CARIBBEAN THAT ARE FUNNELING INTO THE GULF OF 
PAPAGAYO. THE 1504 UTC ASCAT PASS CAPTURED A FRESH TO STRONG NE 
BREEZE DOWNWIND OF PAPAGAYO TO 09N90W. SHIP A8IY2 REPORTED 22 KT 
WINDS NEAR 11N89W AT 1800 UTC. FRESH TO STRONG WINDS ARE 
EXPECTED TO CONTINUE HERE THROUGH TUE WITH HIGH PRES TO THE N 
CONTINUING TO SEND EASTERLY FLOW FROM THE CARIBBEAN THROUGH 
CENTRAL AMERICA. A STRONG BREEZE WILL MOST LIKELY BE SEEN IN THE 
EARLY MORNING HOURS WHEN DRAINAGE FLOW IS AT A MAXIMUM. 

$$
SCHAUER