000
AXPZ20 KNHC 090322
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON NOV 09 2009

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 
0315 UTC.

...TROPICAL LOWS...

.LOW PRES IS CENTERED IS STATIONARY OVER THE PACIFIC COAST OF 
SAN SALVADOR NEAR 13.5N89W AND IS ESTIMATED AT 1008 MB. THE 
CIRCULATION IS MOSTLY A SWIRL OF LOW LEVEL CLOUDS LACKING DEEP 
CONVECTION...BUT RAIN ACCUMULATIONS MAY RESULT IN LOCALIZED 
FLOODING AND EROSION.

.LOW PRES IS CENTERED NEAR 10N123W ESTIMATED AT 1007 MB
WITH A TROUGH EXTENDING NE TO NEAR 15N117W. MULTIPLE CYCLONIC 
SWIRLS ARE NOTED ALONG THE TROUGH. THIS BROAD AREA OF SURFACE 
LOW PRES IS UNDER AN UPPER RIDGE. THE ASSOCIATED UPPER 
DIFFLUENCE ENHANCES INTERMITTENT CONVECTION WHICH ATTEMPTS TO 
BAND.

.LOW PRES IS CENTERED NEAR 10N110W ESTIMATED AT 1007 MB. 
CONVECTION IS CURRENTLY FLARING WITHIN 90 NM OVER THE S 
SEMICIRCLE.   

...ITCZ...

THE ITCZ AXIS EXTENDS FROM 09N83W TO 07N96W TO 12N119W TO 
08N128W TO 09N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED WITHIN 30 NM OF THE COAST OF CENTRAL AMERICA 
FROM 81W TO 86W. SIMILAR CONVECTION IS ALSO OBSERVED WITHIN 150 
NM EITHER SIDE OF A LINE FROM 09N110W TO 13N115W TO 08N126W TO 
09N132W SURROUNDING THE LOW PRES CENTERS PREVIOUSLY DESCRIBED.

...DISCUSSION...

A BROAD UPPER RIDGE DOMINATES THE DISCUSSION AREA S OF A LINE 
FROM 00N132W TO 25N110W TO 10N100W TO 00N109W. DEBRIS MOISTURE 
FROM CONVECTION BETWEEN 114W AND 140W IS STREAMING NE UNDER THE 
RIDGE WITH THE PLUME NOW NARROWING AND IT MOVES ACROSS WESTERN 
MEXICO AT 22N105W AND QUICKLY EVAPORATES BEFORE REACHING CENTRAL 
MEXICO. ITCZ CONVECTION IS ALSO ENHANCED BETWEEN 106W AND 112W 
WITH SOME OF THE DEBRIS MOISTURE NOW SPREADING NE.

AN UPPER TROUGH IS NOTED OVER THE SUBTROPICS TO THE NW OF THE 
PREVIOUSLY DESCRIBED RIDGE...FROM 22N130W TO 14N140W. THE UPPER 
FLOW HAS BECOME ZONAL ELSEWHERE IN THE SUBTROPICS. A PLUME OF 
MOISTURE ORIGINATING IN THE CENTRAL PACIFIC IS STREAMING E OVER 
THE DISCUSSION AREA N OF 27N. 

AN UPPER CYCLONE IS NEAR 33N103W WITH A TROUGH EXTENDING S
ALONG 20N100W TO TO A BASE NEAR 08N91W. A BAND OF DRY UPPER AIR 
IS SWEEPING E ACROSS THE DISCUSSION WITHIN 150 NM OF POINTS 
17N140W TO 23N127W TO 25N108W...THEN THE DRY AIR TURNS SE 
THROUGH THE UPPER TROUGH AND CONTINUES TO PUSH SE RIGHT INTO THE 
TROUGH BASE IN DEEP TROPICAL PACIFIC.

AN UPPER ANTICYCLONE IS OVER THE SW CARIBBEAN NEAR 16N82W WITH A 
RIDGE EXTENDING SW TO NEAR 08N86W. SCATTERED CONVECTION IS 
ENHANCED UNDER THE RIDGE OVER NW COLOMBIA AND ALSO OVER MOST OF 
PANAMA AND COSTA RICA...AND THE DEBRIS MOISTURE IS NOW SPREADING 
SW OVER THE DISCUSSION AREA NE OF A LINE FROM 01N80W TO 10N87W.

AT THE LOW LEVELS HIGH PRES IS CENTERED AT 32N134W 1022 MB WITH 
A RIDGE EXTENDING SE TO NEAR 14N105W. N TO NE TO E WINDS ARE 
GENERALLY 15 TO 20 KT THROUGH THE RIDGE. LARGE NW SWELLS ARE 
WILL SPREAD SE ACROSS THE AREA W OF 100W THROUGH TUE.

GAP WINDS...
N WINDS AT 20 EXPECTED TO RESUME IN THE GULF OF TEHUANTEPEC 
EARLY MON AND INCREASE TO GALE FORCE TUE MORNING.

$$
NELSON