000
AXPZ20 KNHC 220944
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JAN 22 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH IS ALONG 06N77W TO 09N85W TO 03N103W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 03N103W TO 
07N117W TO 04N140W. SCATTERED MODERATE TO STRONG CONVECTION IS 
FROM 04N TO 11N BETWEEN 116W AND 121W. SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF THE 
ITCZ BETWEEN 124W AND 128W. SIMILAR CONVECTION IS WITHIN 180 NM 
N OF THE ITCZ BETWEEN 129W AND 135W.

...DISCUSSION...

A SHARP UPPER TROUGH EXTENDS FROM NW OLD MEXICO NEAR 31N112W TO 
20N120W THEN CONTINUING W OF THE AREA BEYOND 10N140W. THIS 
TROUGH IS ADVECTING MOISTURE FROM THE ITCZ NORTHEASTWARD WITHIN 
480 NM E OF THE UPPER TROUGH AXIS...REACHING TO ACROSS NORTHERN 
MEXICO. OTHERWISE MAINLY DRY AND STABLE AIR DOMINATES THE 
MAJORITY OF THE REMAINDER OF THE DISCUSSION AREA.

1024 MB SURFACE HIGH PRESSURE IS CENTERED NEAR 31N128W WITH A 
RIDGE AXIS EXTENDING TO NEAR 19N110W. THE PRESSURE GRADIENT 
BETWEEN THIS AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING FRESH TO STRONG TRADE WINDS 
FROM 05N TO 20N W OF 130W AND FROM 06N TO 16N BETWEEN 116W AND 
130W AS INDICATED BY RECENT WINDSAT AND ASCAT SCATTEROMETER 
PASSES. THESE TRADE WINDS ARE FORECAST TO PERSIST THROUGH AT 
LEAST MON NIGHT. NW SWELL OF 8-14 FT WITH PEAK WAVE PERIODS OF 
15 SECONDS IS PROPAGATING ACROSS THE NORTHERN WATERS W OF A LINE 
FROM 30N123W TO 24N140W. THIS SWELL WILL GRADUALLY SUBSIDE WHILE 
CONTINUING TO THE S-SE THROUGH THE NEXT FEW DAYS.

FRESH NW WINDS ARE OCCURRING N OF 25N NEAR THE COAST OF THE BAJA 
CALIFORNIA PENINSULA AS CAPTURED BY A RECENT ASCAT PASS. A COLD 
FRONT WILL APPROACH THE PENINSULA MON AND MON NIGHT WITH FRESH 
NORTHERLY WINDS BEHIND IT AND A NEW SET OF NW SWELL. MEANWHILE 
FRESH NORTHERLY WINDS ARE FORECAST BRIEFLY IN THE CENTRAL GULF 
OF CALIFORNIA SUN EVENING THROUGH MON MORNING WITH A TIGHT PRES 
GRADIENT BETWEEN A SURFACE TROUGH OVER NW OLD MEXICO AND HIGH 
PRES W OF THE BAJA CALIFORNIA PENINSULA. FRESH SW-W WINDS ARE 
THEN EXPECTED MON NIGHT AS THE AFOREMENTIONED COLD FRONT MOVES 
CLOSER.

...GAP WINDS...
GULF OF PAPAGAYO...FRESH TO STRONG WINDS OVER THE SW CARIBBEAN 
CONTINUE TO FUNNEL THROUGH THE GAPS IN THE TOPOGRAPHY OF 
NICARAGUA AND COSTA RICA WITH RESULTING FRESH WINDS SPREADING 
ACROSS THE GULF OF PAPAGAYO. THESE WINDS ARE FORECAST TO PERSIST 
THROUGH AT LEAST MON EVENING WITH THE STRONGEST WINDS OCCURRING  
DURING THE LATE NIGHT AND EARLY MORNING HOURS WITH THE ADDED 
COMPONENT OF NOCTURNALLY DRAINAGE FLOW.

$$
LEWITSKY