000
AXPZ20 KNHC 060906
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT SEP 05 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...SPECIAL FEATURES...

A 1007 MB LOW PRESSURE IS CENTERED NEAR 14N123W MOVING WNW AT 
AROUND 15 KT. NUMEROUS MODERATE TO STRONG CONVECTION IS 
OCCURRING WITHIN 150 NM NW SEMICIRCLE...AND IT APPEARS THAT A 
CENTER MAY BE FORMING CLOSER TO DEEP CONVECTION. THIS SYSTEM 
CONTINUES TO SHOW SIGNS OF OF ORGANIZATION AND HAS THE POTENTIAL 
TO BECOME A TROPICAL DEPRESSION DURING THE NEXT DAY OR TWO. 
PRESENTLY... THERE IS A MEDIUM CHANCE OF THIS SYSTEM BECOMING A 
TROPICAL CYCLONE DURING THE NEXT 48 HOURS. COMPUTER MODELS ALSO 
SUGGEST AN INCREASE IN WINDS AND SEAS ASSOCIATED WITH THIS 
LOW... PARTICULARLY ON THE NORTHERN SEMICIRCLE DUE TO THE TIGHT 
PRES GRADIENT BETWEEN THE LOW AND A RIDGE TO THE NORTH. FOR 
NOW... EXPECT WINDS OF 20-30 KT AND SEAS IN THE 8 TO 12 FT RANGE.

...THE ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG 08N78W TO 07N100W TO 
14N119W. THE AXIS CONTINUES AGAIN FROM 12N124W TO 09N140W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED WITHIN 
120 NM S OF AXIS BETWEEN 86W AND 88W...AND WITHIN 150 NM N OF 
AXIS BETWEEN 92W AND 98W.

...DISCUSSION...

CONVECTION THROUGHOUT THE FORECAST REGION IS RESTRICTED TO THE 
ABOVE MENTIONED LOW NEAR 14N123W AND A SMALL SECTION OF THE 
ITCZ. AN UPPER ANTICYCLONE CENTER NEAR 22N140W EXTENDS A RIDGE 
EWD TO NEAR BAJA CALIFORNIA. MODERATE TO STRONG UPPER LEVEL 
SUBSIDENCE AND THE IMPLIED DRY AIR MASS IS NOTED WITHIN THE 
RIDGE N OF 20N. AN UPPER-LEVEL TROUGH ENTERS THE N WATERS NEAR 
31N117W THEN CONTINUES SW TO NEAR 25N127W. BASED ON THE COMPUTER 
MODELS...THE ANTICYCLONE WILL MOVE WWD AND AWAY FROM THE AREA 
WHILE A CUT-OFF WILL APPROACH THE NW CORNER OF THE DOMAIN TUE 
MORNING. 

A SURFACE RIDGE COVERS THE NORTHERN FORECAST WATERS MAINLY N OF 
20N WITH A MODEST INCREASE IN THE TRADEWINDS BETWEEN 16N AND 22N 
AND W OF 130W. NE WINDS OF 20 KT AND SEAS TO 8 FT ARE EXPECTED. 
THESE WINDS MAY INCREASE IN ABOUT 48 HOURS AHEAD OF THE 
DEVELOPING LOW NEAR 14N123W.

THE REMNANTS OF JIMENA ARE STILL PRESENT AS A LOW-LEVEL SWIRL  
NEAR 26N114W...AND SHOULD FULLY DISSIPATE WITHIN THE NEXT 24 
HOURS OR SO. PART OF THE CLOUDINESS ASSOCIATED WITH THIS FEATURE 
CONTINUES TO AFFECT THE SOUTHERN BAJA CALIFORNIA AND COASTAL 
WATERS.

THE REMNANTS OF KEVIN ALSO CONTINUE AS A LOW-LEVEL SWIRL IN THE 
STRATOCUMULUS CLOUDS NEAR 16N130W AND IS ALSO FORECAST TO 
DISSIPATE IN ABOUT 12 TO 24 HOURS. 

LONG PERIOD SWELLS FROM THE NW ARE EXPECTED TO INVADE THE N 
WATERS IN ABOUT 24 HOURS RAISING SEAS TO 9 FT LATE MON INTO 
EARLY TUE. 

$$
GR