000
AXPZ20 KNHC 281519
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT JAN 28 2012

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH 5N78W 8N84W 4N100W. ITCZ AXIS 4N100W 5N105W 
4N140W. SCATTERED MODERATE CONVECTION WITHIN 100 NM S OF AXIS 
FROM 98W-106W.

...DISCUSSION...
A NEGATIVELY TILTED UPPER LEVEL TROUGH EXTENDS FROM 22N140W 
15N130W TO 10N120W. MODERATE TO STRONG SUBSIDENCE WITH 
DRY/STABLE AIR AT THE MIDDLE AND UPPER LEVELS IS S OF THE TROUGH 
AXIS. AN UPPER LEVEL RIDGE EXTENDS FROM 32N127W TO 25N130W 
13N111W. MID/UPPER MOISTURE IS WITHIN THE RIDGE AXIS. AN UPPER 
LEVEL TROUGH EXTENDS FROM NEW MEXICO ACROSS NW MEXICO THROUGH 
CENTRAL BAJA CALIFORNIA TO 27N118W. THE TROUGH IS FORECAST TO 
MOVE SE THROUGH THE NEXT 24 HOURS. STRONG SUBSIDENCE IS FROM 
20N-30N E OF 115W.

SURFACE HIGH PRES RIDGE COVERS THE AREA N OF 17N W OF 115W. NE 
TRADES AT 20 KT ARE OBSERVED ALONG THE SOUTHERN PERIPHERY OF THE 
THE RIDGE FROM 7N-15N W OF 120W...WITH SEAS TO 9 FT. OTHERWISE 
LARGE NLY SWELLS ARE ACROSS MUCH OF THE AREA N OF 18N W OF 110W.

SURFACE TROUGH IS ANALYZED FROM 11N118W TO 6N121W. SCATTERED 
MODERATE CONVECTION WITH THE TROUGH IS FROM 9N-11N BETWEEN
117W-121W.

THE PRES GRADIENT OVER SOUTHERN MEXICO HAS RELAXED AND WINDS ARE 
FORECAST TO DECREASE TO BELOW 20 KT LATER TODAY THROUGH THE GULF 
OF TEHUANTEPEC. HOWEVER ANOTHER REINFORCING COLD FRONT IS 
EXPECTED TO MOVE THROUGH THE GULF OF MEXICO WITH STRONG HIGH 
PRES BUILDING BEHIND THE FRONT. THIS WILL ONCE AGAIN TIGHTEN THE 
PRES GRADIENT ACROSS SOUTHERN MEXICO RESULTING IN GALE FORCE 
WINDS THROUGH THE GULF OF TEHUANTEPEC EARLY SUN.

ELY WINDS TO 20 KT CONTINUE TO BLOW THROUGH THE GULF OF PAPAGAYO
AND ARE EXPECTED TO PERSIST THROUGH THE WEEKEND.

$$
DGS