000
AXPZ20 KNHC 272136
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT NOV 27 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...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 07N78W TO LOW 
PRES NEAR 09N99W TO A SECOND LOW PRES NEAR 09N119W TO 11N140W. 
SCATTERED MODERATE CONVECTION FROM 09N TO 12N BETWEEN 96W AND 
104W. SIMILAR CONVECTION IS 12N111W AND WITHIN 45 NM EITHER SIDE 
OF AXIS W OF 137W.  

...DISCUSSION...
SURFACE RIDGING CONTINUES TO DOMINATE THE N WATERS MAINLY N OF 
15N W OF 110W WHILE A COLD FRONT IS APPROACHING THE NW CORNER OF 
THE FORECAST AREA. FRESH TO STRONG TRADE WINDS ARE STILL NOTED 
ON THE SOUTHERN PERIPHERY OF THE RIDGE. THESE WINDS WILL PERSIST 
MAINLY N OF 10N W OF 120W THROUGH EARLY NEXT WEEK AS HIGH PRES 
BUILDS INTO THE AREA FROM THE NORTH BEHIND THE ADVANCING COLD 
FRONT. THE FRONT WILL PUSH SOUTH AND EXTEND FROM NORTHERN BAJA 
TO 25N125W BY 18Z SUN...THEN WASH OUT FROM CENTRAL BAJA TO 
25N128W BY SUN EVENING. NW TO N WINDS 20 TO 25 KT WILL FOLLOW 
THE FRONT DOWN THE BAJA COAST SUN...FOLLOWED BY 8 TO 10 FT NW 
SWELL. FURTHER SOUTH...A PAIR OF WEAK LOW PRES CENTERS ARE 
WITHIN THE ITCZ. ONE IS NEAR 9N99W AND THE OTHER IS NEAR 9N119W. 
SOME CONVECTIVE ACTIVITY CAN BE FOUND NEAR THE LOW CENTERS. 
THESE FEATURES ARE FORECAST TO MOVE SLOWLY WWD ALONG THE ITCZ. 

GULF OF CALIFORNIA...AN ASCAT PASS FROM THIS MORNING SHOWED NW 
WINDS OF 20 KT OVER THE SOUTHERN GULF OF CALIFORNIA. THE WINDS 
ACROSS THE GULF ARE DIMINISHING AS HIGH PRES OVER THE GREAT 
BASIN WEAKENS AND SHIFTS EAST. EXPECT A NEW ROUND OF FRESH TO 
STRONG NW FLOW IN THE GULF OF CALIFORNIA BY EARLY MON AS HIGH 
PRES BUILDS BEHIND A WEAK COLD FRONT THAT WILL MOVE INTO THE 
AREA AND DISSIPATE SUN.

GAP WINDS...
GALE FORCE WINDS ARE BLOWING THROUGH THE GULF OF TEHUANTEPEC... 
AS COLDER...DENSER AIR FILTERS DOWN THE WESTERN GULF OF MEXICO 
AND THROUGH THE ISTHMUS OF TEHUANTEPEC. A 1628 UTC HIGH 
RESOLUTION ASCAT PASS VERIFIED THE EXISTENCE OF THIS GAP WIND 
EVENT. THE GALE FORCE WINDS WILL PERSIST INTO TONIGHT...THEN 
DIMINISH SUN AS HIGH PRES N OF THE AREA RAPIDLY SHIFTS EAST. 
FURTHER SOUTH...GAP WINDS THROUGH THE GULF OF PAPAGAYO WILL 
PULSE TO 20 KT IN THE EARLY MORNING HOURS...THE COMBINATION OF 
LOCAL NOCTURNAL DRAINAGE FLOW AND SOME ADDED ENHANCEMENT FROM 
EASTERLY GRADIENT FLOW FROM THE SW CARIBBEAN. 

LOOKING AHEAD...A STRONGER COLD FRONT WILL PUSH THROUGH THE 
WESTERN GULF OF MEXICO BY MIDWEEK...AND WILL DELIVER ANOTHER 
ROUND OF GALE FORCE WINDS TO THE GULF OF TEHUANTEPEC...POSSIBLY 
APPROACHING STORM STRENGTH WED.

$$
GR/EC