000
AXPZ20 KNHC 300948
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE AUG 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...SPECIAL FEATURE... 
.SURFACE LOW PRES 16N101W 1004 MB IS EXPECTED TO SLOWLY 
INTENSIFY AND MOVE TO NEAR 17N102W TONIGHT AND NEAR 18N104W WED 
NIGHT WITH THE POSSIBILITY OF TROPICAL CYCLONE FORMATION. 
CURRENTLY SCATTERED MODERATE ISOLATED STRONG CONVECTION IS 
FLARING WITHIN 120 NM OF CENTER. 

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS NW OVER INTERIOR CENTRAL AMERICA 
FROM THE PANAMA AND COLOMBIA BORDER AT 08N77W TO 15N90W...THEN 
TURNS W ALONG 16N INTO THE DEVELOPING SURFACE LOW AT 16N101W... 
CONTINUES SW TO 14N111W...THEN NW INTO A SECOND LOW PRESSURE AT 
18N125W...THEN TURNS SW TO 11N135W WHERE THE LOW LEVEL WINDS 
INDICATE A TRANSITION TO THE ITCZ...WHICH CONTINUES W TO BEYOND 
11N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS 
OBSERVED WITHIN 30 NM OF 05N87W...AND ELSEWHERE N OF 10N BETWEEN 
93W AND 107W...AND WITHIN 15 NM EITHER SIDE OF A LINE FROM 
12N107W TO 12N117W TO 08N127W.

...DISCUSSION...
AN UPPER TROUGH EXTENDS SW FROM VANCOUVER CANADA TO AN UPPER 
CYCLONE CUTTING OFF JUST N OF THE HAWAIIAN ISLANDS. AN UPPER 
ANTICYCLONE NEAR THE TEXAS PANHANDLE HAS AN UPPER RIDGE 
EXTENDING SW ACROSS THE NORTHERN BAJA CALIFORNIA PENINSULA 
THROUGH 20N132W...TO A CREST AT 09N152W. AN UPPER TROUGH 
DISSECTS THE GULF OF MEXICO FROM NE TO SW AND CONTINUES SW 
THROUGH UPPER CYCLONES AT 22N99W...18N120W...15N123W AND 
03N126W. DRY UPPER AIR IS INDICATED OVER THE ENTIRE AREA N OF 
23N...AND FROM 15N TO 23N W OF 120W...AND S OF 15N W OF 130W.
AN UPPER LEVEL ANTICYCLONE IS THE NW CARIBBEAN WITH A RIDGE W TO 
NEAR 17N110W RESULTING IN NORTHEASTERLY UPPER FLOW DOMINATING 
MOST OF TROPICS TO E OF 90W. DEBRIS MOISTURE IS NOTED FROM 10N 
TO 20N E OF 115W AND FROM 03N TO 10N E OF 90W.

A BROAD RIDGE DOMINATES THE PACIFIC WATERS N OF 20N W OF 120W. A 
A PERSISTENT SURFACE LOW PRES IS EMBEDDED IN THE MONSOON TROUGH 
AXIS NEAR 18N125W AND IS EXPECTED TO GRADUALLY DISSIPATE OVER 
THE NEXT DAY OR SO. CROSS EQUATORIAL SOUTHWESTERLY SWELL IS 
NOTED S OF 14N BETWEEN 100W AND 110W AND S OF 11N W OF 110W 
RESULTING IN SEAS TO 11 FT. THESE SOUTHERLY SWELLS WILL 
PROPAGATE NE TO ALONG 20N BETWEEN 90W AND 130W BY WED 
NIGHT...AND REACHING THE NORTHERN BAJA PENINSULA BY EARLY THU. 

$$
NELSON