000
AXPZ20 KNHC 182117
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED OCT 18 2006

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 
2045 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 11N86W 11N120W 7N132W 7N140W. 
NUMEROUS MODERATE/STRONG CONVECTION FROM 9N-14N BETWEEN 86W-96W. 
SCATTERED MODERATE WITHIN 150 NM OF THE AXIS BETWEEN 100W-130W. 
WIDELY SCATTERED SHOWERS/TSTMS WITHIN 150 NM S OF THE AXIS W OF 
130W.

...DISCUSSION...

A SHARP MID/UPPER LEVEL LONGWAVE TROUGH IS MOVING ACROSS THE 
WESTERN U.S. AND EXTREME NW MEXICO WITH A LOW BECOMING CUT-OFF 
ON THE SW FRINGE OF THE TROUGH NEAR 24N130W. THE COMBINATION OF 
THE TROUGH AND CUT-OFF LOW CONTINUE TO PRODUCE A SUBSIDENT 
ENVIRONMENT OVER THE ENTIRE NW PART OF THE DISCUSSION AREA...N 
OF 15N W OF 103W. THE COLD FRONT WHICH HAD MOVED INTO THE AREA 
OVER THE PAST 2 DAYS HAS CONTINUED TO FIZZLE AND IS NOW ONLY A 
DIFFUSE LINE OF STRATOCUMULUS CLOUDS EXTENDING FROM SRN BAJA 
CALIFORNIA TO 23N130W 24N140W. THE LATITUDINAL EXTENT OF THE 
UPPER TROUGH ALONG WITH THE ENTRANCE REGION OF A STRONG UPPER 
JET NEAR NRN BAJA CALIFORNIA HAS PULLED THE ITCZ SLIGHTLY NWD 
BETWEEN 105W-123W.

FARTHER E...A LARGE MID/UPPER HIGH IS CENTERED OVER THE GULF OF 
MEXICO WITH A RIDGE AXIS EXTENDING SW ACROSS MEXICO TO 
12N120W...AND FAIRLY STRONG EASTERLIES RUNNING WWD FROM THE W 
CARIBBEAN ACROSS THE FAR E PACIFIC WATERS. THE LOW-LEVEL FLOW S 
OF MEXICO AND CENTRAL AMERICA IS MAINLY SW/WLY AND STRONG 
CONVERGENCE IS PRODUCING WIDESPREAD CONVECTIVE ACTIVITY CENTERED 
ALONG 12N. A WEAK LOW ALONG THE ITCZ IS CENTERED JUST W OF THE 
NICARAGUAN COAST NEAR 12N88W BUT THE STRONG ELY FLOW IS SHEARING 
ALL DEEP CONVECTION TO ITS W. ONSHORE FLOW SE OF THE LOW 
CONTINUES TO ADVECT MOIST AIR TOWARDS NICARAGUA...COSTA 
RICA...AND PANAMA AND WILL KEEP A CHANCE OF SHOWERS IN THE AREA 
ESPECIALLY IN THE MOUNTAINS.

$$
BERG