000
AXPZ20 KNHC 301501
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN OCT 30 2011

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 01200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY 
THROUGH 1500 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH 9N85W 6N95W 7N105W. INTERTROPICAL CONVERGENCE 
ZONE 7N105W TO 1009 MB LOW NEAR 9N123W 9N135W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 200 NM N AND 100 NM S 
OF AXIS FROM 85W-90W.

...DISCUSSION...
AN UPPER LEVEL TROUGH IS JUST NW OF THE DISCUSSION AREA WITH AN 
UPPER LEVEL RIDGE FROM 26N134W TO 7N135W. SOME UPPER LEVEL 
MOISTURE FROM CONVECTION ASSOCIATED WITH AN UPPER LEVEL CYCLONIC 
CIRCULATION NE OF HAWAII HAS SPREAD INTO THE W PORTION OF THE 
AREA FROM 5N-29N W OF 135W. AN UPPER LEVEL ANTICYCLONIC 
CIRCULATION IS CENTERED OVER THE SOUTHERN TIP OF BAJA CALIFORNIA 
WITH RIDGE EXTENDING N ALONG THE BAJA PENINSULA. S OF THE 
ANTICYCLONE A LARGE UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED 
NEAR 12N114W. STRONG SUBSIDENCE WITH DRY STABLE AIR AT THE 
MIDDLE AND UPPER LEVELS IS ACROSS THE AREA S OF 25N BETWEEN 120W 
AND 90W. THE SUBSIDENCE HAS SUPPRESSED CONVECTIVE ACTIVITY IN 
THIS AREA. ANOTHER UPPER LEVEL RIDGE WITH AXIS FROM THE NW 
CARIBBEAN ACROSS CENTRAL AMERICA TO 4N89W. UPPER LEVEL 
DIFFLUENCE IS ENHANCING CONVECTION FROM 3N-10N E OF 90W.

STRONG PRES GRADIENT ACROSS SOUTHERN MEXICO IS PRODUCING GALE 
FORCE WINDS THROUGH THE GULF OF TEHUANTEPEC. THESE CONDITIONS 
ARE EXPECTED TO LAST THROUGH THE NEXT 48 HOURS. A SURFACE TROUGH 
IS ANALYZED ALONG THE ITCZ FROM 12N121W TO A 1009 MB LOW PRES 
NEAR 9N123W. A FEW SHOWERS ARE NEAR THE LOW PRES CENTER. ANOTHER 
SURFACE TROUGH EXTENDS FROM 12N133W TO 9N135W. N SIGNIFICANT 
WEATHER IS ASSOCIATED WITH THE TROUGH.

$$
DGS