000
AXPZ20 KNHC 240948
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE JAN 24 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 07N77W TO 09N88W TO 05N98W 
WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN ITCZ WHICH 
CONTINUES W TO 07N113W TO 04N130W TO BEYOND 05N140W. SCATTERED 
MODERATE CONVECTION IS DISSIPATING WITHIN 150 NM OF 05N97W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED ALONG A 
NARROW 30 NM WIDE LINE WITH AXIS FROM 07N128W TO 07N135W. BROKEN 
TO OVERCAST LOW CLOUDS ARE OBSERVED S OF 06N E OF 84W AND S OF 
07N BETWEEN 93W AND 108W SURROUNDING THE DISSIPATING CONVECTION. 

...DISCUSSION...

AN UPPER TROUGH EXTENDS ACROSS THE DISCUSSION AREA FROM 32N111W 
TO 19N120W TO AN UPPER CYCLONE JUST W OF THE AREA AT 11N141W. AN 
UPPER ANTICYCLONE HAS SHIFTED E OVER THE NW CORNER NEAR 30N135W 
WITH ITS ENVELOPE OF ANTICYCLONIC FLOW COVERING THE UPPER LEVELS 
N OF 20N W OF 127W. UPPER MOISTURE IS SPREADING SE INTO THE AREA 
N OF 27N BETWEEN 115W AND 127W WITH ADDITIONAL UPPER MOISTURE 
ALONG THE UPPER TROUGH AXIS...AND SPREADING E ACROSS THE 
NORTHERN BAJA CALIFORNIA PENINSULA AND NW OLD MEXICO...AND 
CONTINUING NE ACROSS MOST OF THE SW CONUS.   

AN UPPER ANTICYLONE IS CENTERED AT 09N110W WITH A RIDGE WNW TO A 
FAIRLY SHARP CREST AT 12N129W. UPPER DIFFLUENCE ALONG THE 
SOUTHERN PERIPHERY OF THIS RIDGE IS ENHANCING THE SMALL CLUSTERS 
OF ITCZ CONVECTION PREVIOUSLY DESCRIBED. THE RESULTANT DEBRIS 
MOISTURE FANS OUT OVER THE AREA FROM 05N TO 14N BETWEEN 117W AND 
129W...AND THEN CONCENTRATES INTO 360 NM WIDE PLUME ALONG THE NW 
PERIPHERY OF THE UPPER RIDGE CONTINUING NE ACROSS THE MEXICAN 
COAST AT 22N...TO OVER EXTREME SE TEXAS AND THEN FANNING OUT 
ACROSS THE NORTHERN GULF OF MEXICO. THE SMALL CLUSTERS OF 
CONVECTION WERE ENHANCED ALONG THE ITCZ NEAR 05N95W HAVE NEARLY 
DISSIPATED BUT THE DEBRIS MOISTURE IS SPREADING NE AND WILL MOVE 
ACROSS NORTHERN CENTRAL AMERICA TODAY.
    
AT THE LOW LEVELS A SURFACE HIGH IS NEAR 31N133W AND SHIFTING NE 
WITH TIME. NE TRADES AT 20 TO 25 KT ARE OBSERVED S OF THE RIDGE 
FROM 06N TO 23N TO THE W OF 125W...WITH SEAS 8 TO 12 FT IN LONG 
PERIOD NW SWELL MIXING WITH THE NE TRADE SWELL. NW TO N WINDS AT 
15 TO 20 KT ARE OBSERVED OVER THE PACIFIC WATERS FROM 24N TO 32N 
E OF 124W WITH SEAS 8 TO 11 FT PRIMARILY IN THE LONG PERIOD NW 
SWELL. MIXED N SWELL IS MAINTAINING COMBINED SEAS OF 7 TO 11 FT 
ELSEWHERE W OF LINE FROM THE SOUTHERN TIP OF THE BAJA CALIFORNIA 
PENINSULA TO THE DEEP TROPICS AT 01N140W. AS THE SURFACE HIGH 
SHIFTS NE OF THE DISCUSSION AREA...THE AREA OF ENHANCED TRADES 
WILL EXPAND N TO ALONG 27N ON WED AND TO ALONG 28N ON THU. NW 
SWELLS WILL PROPAGATE SE MIXING WITH N AND NE SWELLS OVER THE 
DISCUSSION AREA TO THE N OF 15N W OF 110W...AND ALSO FROM 07N TO 
15N TO THE W OF 115W...RESULTING IN COMBINED SEAS OF 8 TO 11 FT 
WED. A NEW ROUND OF LO PERIOD NW SWELL WILL PROPAGATE INTO THE 
NW PORTION ON THU DRIVING THE COMBINED SEAS UP TO 14 FT.

A WEAK COLD FRONT IS PASSING ACROSS THE NORTHERN GULF OF 
CALIFORNIA AT THE MOMENT RESULTING IN W WINDS AT 15 TO 20 KT 
OVER THE WATERS TO THE N OF 28N. AS THE FRONT CONTINUES E OF THE 
AREA THIS MORNING AND POST FRONTAL HIGH PRESSURE STRENGTHENS 
THIS AFTERNOON...NORTHERLY WINDS WILL INCREASE TO 20 KT IN THE 
GULF WATERS N OF 27N...FURTHER INCREASING TO 20 TO 25 KT OVER 
THE ENTIRE GULF OF CALIFORNIA LATE TONIGHT INTO WED... 
DIMINISHING BELOW 20 KT ON THU AFTERNOON.
   
...GAP WINDS...
GULF OF PAPAGAYO...NE WINDS WILL CONTINUE TO PULSE AT 15 TO 20 
KT FOR THE NEXT 48 HOURS.

GULF OF TEHUANTEPEC...A COLD FRONT WILL MOVE THROUGH THE SW GULF 
OF MEXICO THU FOLLOWED BY STRONG NORTHERLY WINDS. THESE WINDS 
WILL SURGE THROUGH THE ISTHMUS OF TEHUANTEPEC AROUND SUNSET THU 
AND SHOULD STRENGTHEN TO MINIMAL GALE FORCE THU NIGHT WITH GALE 
CONDITIONS LASTING THROUGH LATE FRI NIGHT. GUIDANCE IS 
SUGGESTING THE NORTHERLY WINDS WILL DIMINISH TO 20 TO 25 KT 
SAT...BUT INCREASE AGAIN TO A GALE SAT NIGHT. EXPECT ADJUSTMENTS 
TO THE STRENGTH AND TIMING OF THESE EVENTS IN FUTURE MODEL 
RUNS.

$$
NELSON