000
AXPZ20 KNHC 180411
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN FEB 18 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...

ITCZ AXIS ALONG 3N78W 4N82W 2N100W 7N120W 2N140W. SCATTERED 
MODERATE WITHIN 90 NM OF THE AXIS BETWEEN 85W AND 91W...AND 
WITHIN 60 NM OF THE AXIS BETWEEN 113W AND 137W. 

...DISCUSSION...

UPPER AIR...
BLOCKING PATTERN OVER THE AREA IS BREAKING DOWN AS A SHARP 
UPSTREAM MID-UPPER LEVEL TROUGH IS SWEEPING INTO THE FAR NW 
PORTION OF THE AREA EXTENDING FROM 35N132W TO 30N140W. THIS 
TROUGH HAS DISPLACED THE RIDGE EASTWARD TO THE INTERMOUNTAIN 
WEST AND ALLOWED AN ELONGATED CYCLONIC CIRCULATION WITH A MEAN 
CENTER NEAR 28N122W TO MOVE NNEWD AT 10-15 KT. CIRCULATION HAS 
LEFT A BROAD TROUGH IN ITS WAKE OVER THE AREA N OF 12N W OF 
115W. STRONGLY DIFFLUENT FLOW EXISTS E OF THE CYCLONIC 
CIRCULATION AND WAS PRODUCING AN AREA OF MULTILAYERED CLOUDS AND 
EMBEDDED SHOWERS OVER BAJA CALIFORNIA AND THE SEA OF CORTEZ N OF 
26N. 

A LARGE DEEP LAYERED ANTICYCLONE NEAR 13N79W DOMINATED THE 
CARIBBEAN...CENTRAL AMERICA AND THE TROPICAL PACIFIC E OF 
110W. VERY STRONG SUBSIDENCE/DRY AIR ALOFT COVERED THE ENTIRE 
AREA WITH THE EXCEPTION OF SOME MID-UPPER LEVEL CONVECTIVE 
DEBRIS OVER THE AREA S OF 10N E OF 95W. STRONG MID-UPPER LEVEL 
FLOW BETWEEN THE CYCLONIC CIRCULATION NOTED ABOVE AND THE LARGE 
ANTICYCLONE WAS ADVECTING MID TO UPPER LEVEL MOISTURE EWD OVER 
MEXICO AND THE EXTREME WESTERN GULF.  

SURFACE...
A STATIONARY FRONT WAS OVER THE FAR NW CORNER OF THE AREA BUT 
WAS WEAKENING CONSIDERABLY IN THE FACE OF A RIDGE OF HIGH 
PRESSURE COVERING THE AREA N OF 12N W OF 110W. 

GAP WINDS...
35 KT WINDS FROM A 0048 UTC QUIKSCAT PASS AND SURFACE 
OBSERVATIONS FROM SALINA CRUZ INDICATE GALE CONDITIONS HAVE 
COMMENCED OVER THE GULF OF TEHUANTEPEC. LATEST GFS AND NAM MODEL 
GUIDANCE SUGGEST WINDS WILL CONTINUE TO INCREASE ON SUNDAY AND 
REACH STORM FORCE...50-55 KT BY 18-24 HOURS AND RESULT IN THE 
ELEVENTH STORM FORCE WIND EVENT OF THE 2006-2007 SEASON. IN 
ADDITION THIS NEXT COLD SURGE WILL SPREAD FAR TO THE SOUTH OVER 
CENTRAL AMERICA AND ALLOW WINDS TO INCREASE TO 25-30 KT IN THE 
GULF OF PAPAGAYO WITHIN 24 HOURS AND REACH GALE FORCE BY 36 
HOURS. WINDS WILL ALSO INCREASE IN THE GULF OF PANAMA AND REACH 
20 KT BY 48 HOURS.

$$
COBB