000
AXPZ20 KNHC 170935
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE OCT 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 93W N OF 5N IS MOVING W ABOUT 10 KT. ONLY 
SCATTERED MODERATE CONVECTION ASSOCIATED WITH THE ITCZ IS ALONG 12N. 
DRY STABLE AIR ALOFT ON THE S PERIPHERY OF A STRONG RIDGE IN THE NW 
CARIBBEAN IS CONTINUING TO SUPPRESS CONVECTION.

...ITCZ...
AXIS 10N86W 13N100W 10N117W 6N135W 6N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF THE AXIS BETWEEN 94W 
AND 110W. SCATTERED MODERATE CONVECTION WITHIN 90 NM OF 8N124W.

...DISCUSSION...
ACTIVE CONVECTION CONTINUES E OF 110W BETWEEN 10N AND 20N. THIS 
UNSETTLED WEATHER IS ENHANCED BY SEVERAL FEATURES. THE CONTRIBUTING 
SURFACE FEATURES ARE THE ITCZ AND A TROPICAL WAVE ALONG 93W. UPPER 
DIFFLUENCE IS A PRIMARY FACTOR WITH MOIST SW FLOW ADVECTING DEEP 
TROPICAL MOISTURE BETWEEN A STRONG RIDGE IN THE NW CARIBBEAN AND AN 
ELONGATED UPPER TROUGH WHICH EXTENDS FROM THE WRN U.S. SOUTHWESTWARD 
ACROSS THE E PAC FROM CENTRAL BAJA TO AN UPPER LOW NEAR 20N114W.

THE REMAINDER OF THE DISCUSSION AREA REMAINS FAIRLY QUIET. A RIDGE / 
TROUGH UPPER LEVEL PATTERN EXISTS WITH AN UPPER ANTICYCLONE CENTERED 
NEAR 13N138W AND THE ELONGATED UPPER TROUGH TO ITS E AS DESCRIBED 
ABOVE. MODERATE TO STRONG SUBSIDENCE AND DRY STABLE UPPER LEVEL AIR 
IS NOTED ON WATER VAPOR N OF 18N. PATCHES OF MID/UPPER LEVEL MOISTURE
ARE STREAMING ENE INTO THE WESTERN PART OF THE REGION AHEAD OF A 
DEEP-LAYERED TROUGH W OF 140W. ELSEWHERE AT THE SURFACE A 1024 MB 
HIGH IS CENTERED NEAR 38N138W WITH RIDGING EXTENDING SOUTHEAST TO 
NEAR 22N125W. HIGH PRESSURE COVERS THE AREA N OF 23N W OF 125W. A 
BROAD AREA OF LOW PRES...RESIDUAL FROM FORMER TROPICAL DEPRESSION 
NORMAN...COVERS THE EASTERN PORTION OF THE AREA N OF 10N E OF 115W.

LOOKING AHEAD OVER THE NEXT FEW DAYS...GLOBAL MODELS INDICATE A 
DEEPENING SURFACE TROUGH E OF 110W WITH WESTERLY WINDS STRENGTHENING 
S OF THE TROUGH AXIS. THE MID/UPPER LEVEL TROUGH IN THE ERN PORTION 
OF THE AREA IS FORECAST TO LIFT OUT WITH A LARGE UPPER LOW FORMING 
OVER THE WESTERN PORTION OF THE AREA BY MID-WEEK. THE SFC RIDGE WILL 
STRENGTHEN SLIGHTLY THROUGH WED THEN WEAKEN THU THROUGH SAT.

$$
MUNDELL