000
AXPZ20 KNHC 021544
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON JAN 02 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 
1415 UTC.

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

MONSOON TROUGH EXTENDS FROM 05N78W TO 08N85W TO 04N97W. 
THEN...THE ITCZ CONTINUES FROM 04N97W TO 06N110W TO 06N130W TO 
05N140W. NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION CAN BE 
FOUND FROM 03N TO 07N E OF 79W TO THE COAST OF COLOMBIA WHERE A 
1008 MB LOW PRES IS OBSERVED. SCATTERED MODERATE TO ISOLATED 
STRONG CONVECTION IS WITHIN 80 NM EITHER SIDE OF ITCZ AXIS 
BETWEEN 108W AND 110W. SCATTERED MODERATE CONVECTION IS WITHIN 
150 NM N OF ITCZ BETWEEN 132W AND 138W.

...DISCUSSION...

A LONG WAVE TROUGH ENTERS THE FORECAST AREA NEAR 30N133W AND 
EXTENDS SW TO BEYOND 18N140W. THIS TROUGH SUPPORTS A SURFACE 
COLD FRONT THAT NOW STRETCHES FROM 30N130W TO 23N136W. ALTHOUGH 
THE FRONT WILL QUICKLY DISSIPATE...A RATHER IMPRESSIVE BATCH OF 
LONG PERIOD NW SWELLS BEHIND THE FRONT WILL PROPAGATE INTO THE 
AREA MIXING WITH NE SWELL...AND DRIVING COMBINED SEA HEIGHTS UP 
TO ABOUT 20 FT OVER THE FAR NW PORTION OF THE AREA. THESE LARGE 
SEAS ARE FORECAST BY THE NOAA WAVEWATCH MODEL GUIDANCE TO REACH 
THE NORTHERN BAJA CALIFORNIA PENINSULA ON TUE NIGHT WITH SEAS IN 
THE 8 TO 12 FT RANGE BY WED MORNING...WHEN ANOTHER SET OF NW 
SWELL IS FORECAST TO REACH THE FAR NW PART OF THE AREA.    

AHEAD OF THE LONG WAVE TROUGH...THE UPPER PATTERN IS MARKED BY A 
HIGHLY AMPLIFIED ANTICYCLONIC FLOW. SATELLITE WATER VAPOR 
IMAGERY SHOWS EXTENSIVE BROKEN TO OVERCAST MOSTLY MID AND UPPER 
LEVEL CLOUDS BEING TRANSPORTED N AND NE UP OVER THE RIDGE IN THE 
DIFFLUENT FLOW ALOFT. 

A SECOND LONGWAVE TROUGH IS MOVING ACROSS EASTERN N AMERICA AND 
CONTINUES S ACROSS THE WESTERN GULF OF MEXICO AND THE ISTHMUS OF 
TEHUANTEPEC TO A BASE OVER THE EPAC NEAR 12N95W. WATER VAPOR 
IMAGERY SHOWS MODERATE SUBSIDENCE AND ASSOCIATED DRY AIR ALOFT S 
E OF 100W WITH THE EXCEPTION OF THE CONVECTION NEAR THE COAST OF 
COLOMBIA MENTIONED ABOVE. 

GAP WINDS...

GULF OF TEHUANTEPEC...
N-NE WINDS HAVE INCREASED TO GALE FORCE WINDS OF 30-40 KT AS 
SUGGESTED BY THE LATEST HIGH RESOLUTION ASCAT PASS. THE VERY 
STRONG PRES GRADIENT OVER MEXICO WILL FURTHER STRENGTH THESE 
WINDS AS THEY FUNNEL THROUGH THE CHIVELA PASS AND IN TO THE GULF 
OF TEHUANTEPEC THROUGH TODAY REACHING TO STORM FORCE OF 35-50 KT 
TONIGHT. LATEST MODEL GUIDANCE SHOWS THESE STORM CONDITIONS 
CONTINUING THROUGH EARLY WED BEFORE DIMINISHING BACK TO MINIMAL 
GALE FORCE. THE ASSOCIATED SEAS ARE FORECAST TO PEAK UP TO 20 FT 
ON TUE WITH N AND NE SWELL PROPAGATING S ACROSS THE WATERS N OF 
07N BETWEEN 93W AND 110W LATE TUE.

GULF OF PAPAGAYO...
FRESH TO STRONG TRADE WINDS OVER THE WESTERN CARIBBEAN CONTINUE 
TO FUNNEL THROUGH NICARAGUA INTO THE GULF OF PAPAGAYO. PEAK WINDS
WILL BE 20-25 KT DURING THE LATE NIGHT AND EARLY MORNING HOURS 
BUT INCREASE TO 20-30 KT TUE NIGHT AS A COLD FRONT MOVES INTO 
THE SW CARIBBEAN. DOWNSTREAM SEAS ARE AT 6-8 FT BUT WILL 
INCREASE TO AROUND 12 FT EARLY WED MORNING IN WATERS FROM 
08N-12N BETWEEN 85W AND 90W. 
      
GULF OF PANAMA...
N-NE WINDS AT 20 KT FUNNELING S ACROSS PANAMA WILL CONTINUE 
WITH ONLY LITTLE CHANGE THROUGH THE NEXT 48 HOURS AS A WEAK 1009 
MB LOW ON THE MONSOON TROUGH AT 05N78W REMAINS ABOUT STEADY STATE
HELPING TO USHER THESE WINDS SWD FROM CENTRAL AMERICA TOWARDS 
THE MONSOON TROUGH.

$$
GR/JA