000
AXPZ20 KNHC 042202
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JAN 04 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...
AXIS IS ALONG 4N78W 6N90W 5N95W 9N120W 4N140W. SCATTERED 
MODERATE CONVECTION WITHIN 90 NM EITHER SIDE OF AXIS FROM
105W-108W.

...DISCUSSION...
SPLIT UPPER LEVEL FLOW LIES OVER THE EASTERN PACIFIC...WITH THE 
SOUTHERN STREAM JET STRETCHING THROUGH FORECAST WATERS ALONG AN 
AXIS FROM NEAR 10N127W NE TO 20N120W...TO 25N105W...AND THEN E 
ALONG 25N THROUGH THE GULF OF MEXICO. UPPER LEVEL MOISTURE IS 
ABUNDANT S OF THIS JET AXIS AS DENOTED BY THE CIRRUS BAND SEEN 
ON SATELLITE IMAGERY JUST S OF THE JET AXIS. A SURFACE TROUGH 
EMBEDDED IN THE ITCZ LIES NEAR THE REAR RIGHT QUADRANT OF THE 
UPPER JET...WITH ANY DEEP CONVECTION ASSOCIATED WITH THE TROUGH 
BEING BLOWN NE AWAY FROM THE ITCZ UNDER THE STEERING FLOW OF THE 
JET. SATELLITE DERIVED PRECIPITABLE WATER IMAGERY SHOWS A POOL 
OF LOW TO MID LEVEL MOISTURE BETWEEN THIS SURFACE TROUGH AND A 
1008 MB SURFACE LOW NEAR 08N112W. SCATTERED MODERATE CONVECTION 
CURRENTLY LIES E OF THIS LOW WITHIN 150 NM EITHER 
SIDE OF THE ITCZ AXIS BETWEEN 105W AND 109W. THE SOUTHERN STREAM 
UPPER JET IS EXPECTED TO SLOWLY MOVE NORTHWARD OVER THE NEXT FEW 
DAYS AND THE AREA OF AVAILABLE MOISTURE AND UPPER LEVEL 
DIFFLUENCE ON ITS SE EDGE...ALONG WITH THE GREATEST CHANCE OF 
CONVECTION...IS EXPECTED TO SHIFT N WITH IT.

AT THE SURFACE...1022 MB HIGH PRES NEAR 32N127W WILL REMAIN 
RELATIVELY STATIONARY OVER THE NEXT FEW DAYS...IMPEDING THE 
PROGRESS OF THE WEAK FRONTAL BOUNDARIES ON ITS WESTERN SIDE. A 
COLD FRONT CURRENTLY LIES JUST NW OF FORECAST WATERS STRETCHING 
FROM 35N144W TO 25N155W. GALE CONDITIONS ARE FOUND IN THE 
SOUTHERLY FLOW AHEAD OF THE FRONT...BUT WINDS OVER FORECAST 
WATERS ARE ONLY 20 KT AT THIS TIME ACCORDING TO THE 1536 WINDSAT 
PASS. THIS FRONT WILL MERGE WITH ANOTHER COLD FRONT TO ITS NW. 
DESPITE THIS REINFORCING ENERGY...THE LEADING FRONT IS NOT 
EXPECTED TO PENETRATE THE FORECAST AREA.  HOWEVER...THE PRES 
GRADIENT BETWEEN IT AND THE HIGH WILL KEEP SOUTHERLY WINDS TO 20 
KT OVER NW WATERS THROUGH WED. SWELL FRONT THIS COLD FRONT WILL 
REACH NW WATERS TUE...BRINGING SEAS TO 14 FT WED.

GAP WINDS...A WINDSAT PASS FROM 1218 UTC SHOWED WINDS TO 34 KT 
IN THE GULF OF TEHUANTEPEC THIS MORNING. UNFORTUNATELY...THE 
1558 ASCAT PASS MISSED THE AREA. CONSIDERING THE BUILDING HIGH 
PRES OVER EASTERN MEXICO...CONFIDENCE IS HIGH THAT WINDS ARE 
EXCEEDING GALE FORCE AT THIS TIME. THESE GALE FORCE ARE EXPECTED 
TO INCREASE TO STORM FORCE OVERNIGHT AS A NEW SURGE STRONG 
NORTHERLY FLOW MOVES AROUND THE EASTERN EDGE OF THE RIDGE 
BRINGING COLD AND DRY AIR FROM THE NORTH AMERICAN CONTINENT 
THROUGH THE GULF OF MEXICO AND THE ISTHMUS OF TEHUANTEPEC. THE 
STORM EVENT IS EXPECTED TO DIMINISH BACK TO A GALE BY TUE 
EVENING AND DIMINISH FURTHER TO A MINIMAL GALE BY WED AFTERNOON. 
 
GULF OF PAPAGAYO...NE WINDS OF 20 TO 25 KT ARE EXPECTED TO 
CONTINUE INTO WED.

GULF OF PANAMA...N WINDS AT 15 TO 20 KT ARE EXPECTED TO LINGER 
FOR THE NEXT FEW DAYS.

GULF OF CALIFORNIA...THE ASCAT PASS FROM 1734 UTC SHOWS A SOLID 
AREA OF 20 KT WINDS IN THE CENTRAL GULF OF CALIFORNIA. THESE 
WINDS ARE EXPECTED TO CONTINUE THROUGH TUE 
MORNING...DIMINISHING AS THE HIGH PRES OVER THE GREAT BASIN 
ERODES.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE
  
$$
SCHAUER