000
AXPZ20 KNHC 230956
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON JAN 23 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 
0945 UTC.

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

THE MONSOON TROUGH EXTENDS FROM 08N77W TO 07N87W WHERE LOW LEVEL 
WINDS INDICATE A TRANSITION TO AN ITCZ WHICH CONTINUES W TO 
03N100W TO 06N110W TO 07N126W TO BEYOND 04N140W. SCATTERED 
MODERATE CONVECTION IS DISSIPATING WITHIN 30 NM OF 03N98W AND 
05N107W AND 06N111W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED WITHIN THE AREA BOUNDED BY 07N TO 13N 
BETWEEN 121W AND 132W.

...DISCUSSION...

AN INITIAL UPPER TROUGH EXTENDS FROM 28N113W TO 20N120W TO 
13N135W TO AN UPPER CYCLONE AT 09N138W AND IS BEING REINFORCED 
BY A SECOND UPPER TROUGH CURRENTLY EXTENDING FROM 32N120W TO 
26N126W. DRY UPPER AIR IS NOTED NW OF THE INITIAL TROUGH TO 30N. 
UPPER MOISTURE ACCOMPANIES THE SECOND UPPER TROUGH WITH MOISTURE 
CONTINUING E ACROSS THE SW CONUS. AN UPPER ANTICYLONE IS 
CENTERED AT 12N102W WITH A RIDGE W TO 07N115W. UPPER DIFFLUENCE 
E OF THE INITIAL TROUGH...AND ALONG THE SOUTHERN PERIPHERY OF 
THE RIDGE...ENHANCED ITCZ CONVECTION EARLIER WITH THE DEBRIS 
MOISTURE SPREADING NE ALONG THE NW PERIPHERY OF THE RIDGE... 
ROUGHLY WITHIN 240 NM EITHER SIDE OF A LINE FROM 13N117W TO 
24N107W...THEN ACROSS NORTHERN MEXICO AND THE NORTHERN GULF OF 
MEXICO. SMALL CLUSTERS OF CONVECTION WERE ENHANCED ALON THE ITCZ 
BETWEEN 90W AND 110W BUT ARE DISSIPATING WITH THE DEBRIS 
MOISTURE EVAPORATING IN THE DRY UPPER AIR THAT DOMINATES THE 
DISCUSSION AREA S OF 20N E OF 109W. 
      
AT THE LOW LEVELS A RIDGE EXTENDS W TO E ALONG 26N WITH EMBEDDED 
SURFACE HIGHS NEAR 26N140W AND 28N122W. A WEAK COLD FRONT 
EXTENDS FROM 32N124W TO 28N135W. NE TRADES AT 20 TO 25 KT ARE 
OBSERVED S OF THE RIDGE FROM 05N TO 18N TO THE W OF 128W...WITH 
SEAS 8 TO 12 FT IN NE SWELL. NW TO N WINDS AT 15 TO 20 KT ARE 
OBSERVED OVER THE PACIFIC WATERS FROM 26N TO 32N E OF 117W WITH 
SEAS 7 TO 11 FT PRIMARILY IN NW SWELL. MIXED N SWELL IS 
MAINTAINING COMBINED SEAS OF 8 TO 13 FT ELSEWHERE W OF LINE FROM 
THE BAJA CALIFORNIA PENINSULA AT 26N TO THE DEEP TROPICS AT 
06N125W. AS THE SURFACE HIGHS SHIFT NE OF THE DISCUSSION AREA 
THE AREA OF ENHANCED TRADES WILL EXPAND N TO ALONG 22N ON TUE 
AND ALONG 26N ON WED. NW SWELLS WILL PROPAGATE SE MIXING WITH N 
AND NE SWELLS OVER THE DISCUSSION AREA TO THE N OF 14N W OF 110W 
AND ALSO FROM 05N TO 14N TO THE W OF 107W...RESULTING IN 
COMBINED SEAS OF 8 TO 12 FT BY WED.

AS THE COLD FRONT REACHES THE GULF OF CALIFORNIA TUE WINDS WILL 
BECOME WESTERLY AT 15 TO 20 KT JUST AHEAD OF THE FRONT OVER THE 
GULF WATERS FROM 28N TO 31N. AS THE POST FRONTAL HIGH PRESSURE 
STRENGTHENS TUE AFTERNOON NORTHERLY WINDS WILL INCREASE TO 20 KT 
IN THE GULF WATERS BETWEEN 25N AND 28W...FURTHER INCREASING TO 
20 TO 25 KT OVER THE ENTIRE GULF OF CALIFORNIA TUE NIGHT INTO 
WED.
   
...GAP WINDS...
GULF OF PAPAGAYO...FRESH TO STRONG WINDS IN THE SW CARIBBEAN 
FUNNELING THROUGH NICARAGUA AND COSTA RICA IS SPREADING ACROSS 
THE GULF OF PAPAGAYO AND THE PACIFIC FROM 10N TO 12N E OF 90W.
THESE WINDS WILL PERSIST THROUGH TONIGHT THEN DIMINISH TUE 
AFTERNOON.

$$
NELSON