000
AXPZ20 KNHC 242112
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 24 2007

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 4N77W 4N92W 10N106W 5N125W 4N140W. 
SCATTERED MODERATE WITHIN 75 NM OF THE AXIS E OF 84W... AND 
BETWEEN 90W AND 93W.

...DISCUSSION...

CLASSIC OMEGA BLOCK REMAINS IN PLACE OVER THE WATERS N OF 20N 
WITH A RIDGE AXIS ALONG 118W/119W NWD INTO CALIFORNIA AND
NEVADA...FLANKED BY A DEEP CLOSED LOW OVER NRN MEXICO NEAR 
29N107W AND A MORE PROGRESSIVE BUT NEGATIVELY TILTED TROUGH 
BRUSHING THE AREA ALONG 132W/133W. A NEAR ZONAL SUBTROPICAL JET 
IS POSITIONED ALONG 19N/20N WITH CORE SPEEDS OF 90-100 KT...THEN 
TURNS NE INTO N/CENTRAL MEXICO ON THE SE PERIPHERY OF THE CLOSED 
LOW. A WEAK COLD FRONT HAS MOVED INTO THE FAR NW CORNER OF THE 
AREA FROM 30N135W 27N140W WITH ISOLATED SHOWERS WITHIN THE 
FRONTAL BAND...AND FURTHER WEAKENING IS ANTICIPATED DURING THE 
NEXT 6-12 HRS. OVERALL THE MIDDLE AND UPPER ATMOSPHERE ARE 
FAIRLY SUBSIDENT AND HAS THUS LIMITED THE VERTICAL EXTENT OF 
CLOUD COVER EVEN IN THE ITCZ...AT LEAST W OF 95W/100W.

FARTHER E...A SURFACE TROUGH EMBEDDED WITHIN THE ITCZ IS LOCATED 
SW OF ACAPULCO FROM 7N107W TO 16N101W AND PROVIDES THE DIVIDING 
LINE FOR WEAK 5-10 KT WINDS TO THE E...AND STRONGER 20 KT NE 
WINDS TO THE W. THIS FEATURE HAS WEAKENED SINCE YESTERDAY IN 
TERMS OF THE ASSOCIATED LOW-LEVEL CONVERGENCE. WINDS OVER THE 
GULF OF TEHUANTEPEC ARE 20-25 KT BUT ARE EXPECTED TO INCREASE TO 
GALE FORCE WITHIN THE NEXT 18 HOURS AS HIGH PRES BUILDS OVER THE 
GULF OF MEXICO. PAPAGAYO WINDS WILL REMAIN STEADY 20 KT FOR THE 
NEXT FEW DAYS. WINDS OVER THE GULF OF PANAMA ARE UNEXPECTEDLY 
20-25 KT ACCORDING TO QUIKSCAT DATA FROM THIS MORNING...AND 
EXPECT THESE WINDS TO CONTINUE UNTIL THU EVENING BASED ON 925 MB 
WIND GUIDANCE FROM THE GFS.

THE CLOSED LOW OVER NW MEXICO IS FORCING A STRONG 125 KT JET 
CORE OF THE SUBTROPICAL JET ACROSS N/CENTRAL MEXICO WITH A 
PROLIFIC BAND OF MID/UPPER LEVEL CLOUDINESS ACROSS MUCH OF THE 
COUNTRY. A STATIONARY FRONT IS DRAPED ACROSS THE MOUNTAINOUS 
TERRAIN FROM NEAR COATZACOALCOS NWWD TO DURANGO AND COLD 
LOW-LEVEL FLOW IS BEING FORCED ONTO THE MEXICAN PLATEAU WITH 
ABNORMALLY COLD TEMPERATURES OF 1 TO 5 DEGREES CELSIUS AND LOW 
STRATUS E OF THE SIERRA MADRE OCCIDENTALS.

$$
COBB