000
AXPZ20 KNHC 180359
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN NOV 18 2007

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0330 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N82W 6N86W 8N100W 9N125W 9N140W. 
NUMEROUS MODERATE TO STRONG FROM 3N TO 8N BETWEEN 79W AND 82W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 45-60 NM OF AXIS 
BETWEEN 111W AND 117W.

...DISCUSSION...

E OF 105W...
A DIGGING MID TO UPPER LEVEL TROUGH EXTENDS FROM CENTRAL TEXAS 
AND EXTENDS SWWD ACROSS W-CENTRAL MEXICO AND THE ADJACENT 
WATERS. THE TROUGH HAS BROKEN DOWN THE UPPER RIDGE WHICH WAS 
LOCATED OVER SE MEXICO AND CENTRAL AMERICA...WITH BROAD SW/W 
FLOW STREAMING FROM THE FAR E PACIFIC WATERS INTO THE W 
CARIBBEAN....GULF OF MEXICO AND ADJACENT LAND AREAS. HOWEVER...A 
WELL-DEFINED MID-LEVEL RIDGE IS STILL ANCHORED ALONG 18N E OF 
100W AND IS PRODUCING MODERATE SUBSIDENCE OVER MUCH OF THE 
REGION...BECOMING STRONGER S OF 10N TOWARD THE EQUATOR MAINLY E 
OF 95W. FAIRLY DRY LOW-LEVEL AIR N OF THE ITCZ HAS KEPT SKIES 
MOSTLY CLOUD-FREE WITH THE EXCEPTION OF SCATTERED SHOWERS/TSTMS 
ON THE WINDWARD/EASTERN SIDES OF COSTA RICA AND PANAMA. BROKEN 
STRATOCUMULUS IN STREAMERS LIE S OF THE ITCZ DUE TO HIGHER 
MOISTURE VALUES AND INSTABILITY OVER COOLER OCEAN WATERS.

THE EDGE OF A 0106 UTC QUIKSCAT PASS INDICATED WINDS OF 5-10 KT 
OVER THE GULF OF TEHUANTEPEC. LIGHT WINDS SHOULD PREVAIL UNTIL 
THE NEXT SURGE COMMENCES IN ABOUT 24 HOURS AND CONTINUES INTO 
MON WITH WINDS ONCE AGAIN INCREASING TO 25 TO 30 KT BY LATE MON. 
...POSSIBLY REACHING NEAR GALE CONDITIONS. QUIKSCAT MISSED MOST 
OF THE GULF OF PAPAGAYO BUT STILL SHOWED 15 KT WINDS SUGGESTING
THE POSSIBILITY OF 20 KT WINDS FURTHER OFFSHORE. 

W OF 105W...
A DEEP-LAYERED TROUGH AXIS IS SWINGING ACROSS NW MEXICO FROM 
W-CENTRAL TEXAS TO SRN BAJA CALIFORNIA...AND HAS PHASED WITH 
ANOTHER UPPER TROUGH LOCATED DEEPER WITHIN THE TROPICS ALONG 
108W. MODERATE/STRONG SUBSIDENCE ASSOCIATED WITH THE NRN PART OF 
THE TROUGH IS PUSHING ACROSS THE SRN PORTION OF THE GULF OF 
CALIFORNIA AND NW MEXICO AND IS PROVIDING AN EFFICIENT CAP TO 
THE MARINE LAYER W OF BAJA...WITH COASTAL FOG/STRATUS BANKED 
OVER THE W COAST N OF 27N. W OF THE TROUGH...A BROAD NE/SW 
ORIENTED UPPER RIDGE EXTENDS FROM 27N140W TO 30N127W AND IS 
PROVIDING ADDITIONAL SUBSIDENCE N OF 24 ON THE FRINGE OF A 
50-60 KT WESTERLY SUBTROPICAL JET. THE JET ORIGINATES FROM A 
LARGE WELL DEFINED CUT-OFF LOW LOCATED ABOUT 300 NM SE OF THE 
BIG ISLAND OF HAWAII. BROAD DIFFLUENCE E OF THE LOW IS PRODUCING 
WIDESPREAD MID/HIGH LEVEL CLOUDINESS GENERALLY FROM 12N-24N 
AND EXTENDING EWD TOWARD MEXICO. CURRENT SATELLITE TRENDS 
SUPPORT MODEL GUIDANCE WHICH IS FORECASTING A SURFACE LOW PRES 
SHOULD DEVELOP BENEATH THIS AREA OF DIVERGENCE OVER THE NEXT 48 
HRS OR SO. THE LOW HOWEVER IS EXPECTED TO REMAIN W OF 140W AND 
MAY INCREASE EASTERLY WINDS TO 20-25 KT OVER THE FAR WRN PART OF 
THE DISCUSSION AREA.

$$
COBB