000
AXPZ20 KNHC 220324
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON SEP 22 2008

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 
0300 UTC.

...SPECIAL FEATURES...

THE LAST FEW VISIBLE SATELLITE IMAGES THIS EVENING INDICATED 
THAT A BROAD AREA OF SURFACE LOW PRESSURE MIGHT BE DEVELOPING 
ALONG A SURFACE TROUGH LYING ALONG 16N BETWEEN 100W AND 106W. 
THE SURFACE LOW SEEMS TO BE FORMING NEAR A DYING CONVECTIVE 
CLUSTER...WHICH GENERATED A WELL-DEFINED MID-LEVEL CYCLONIC 
CIRCULATION IN THE VICINITY OF 16.5N102.5W EARLIER THIS 
AFTERNOON. HOWEVER...MUCH OF THE EARLIER CONVECTION HAS 
COLLAPSED SINCE ...WITH ALL THAT REMAINS NOW BEING A SOLID 
NORTH-SOUTH LINE OF CONVECTION EXTENDING FROM 14N104W TO NEAR 
MANZANILLO MEXICO. OVERALL...THIS SYSTEM HAS BECOME INCREASINGLY 
LESS ORGANIZED OVER THE PAST 24 HOURS. NEVERTHELESS...MODEL 
GUIDANCE SUGGESTS THE POTENTIAL FOR TROPICAL CYCLONE DEVELOPMENT 
DURING THE NEXT DAY OR TWO AS IT HEADS WNW AT 10 KT.

...TROPICAL WAVES...

A TROPICAL WAVE ALONG 88W N OF 09N INTO CENTRAL AMERICA IS 
MOVING W ABOUT 10 KT. A BROAD BUT POORLY-DEFINED AREA OF LOW-
TO MID-LEVEL CYCLONIC TURNING IS NOTED IN SATELLITE IMAGERY.
ENHANCED CONVECTION IS NOTED ALONG THE W COAST OF CENTRAL 
AMERICA FROM COSTA RICA NORTHWEST THROUGH EL SALVADOR.

A TROPICAL WAVE ALONG 122W FROM 08N TO 16N IS MOVING W 5 KT. A 
1011 MB LOW IS ATTACHED TO THE WAVE NEAR 11N BUT IS WELL E OF
THE NEAREST DEEP CONVECTION. IN FACT...LAST VISIBLE IMAGES 
REVEALED A BROAD CYCLONIC TURNING...WITH NUMEROUS SCATTERED
ISOLATED STRONG CONVECTION BETWEEN 60 AND 210 NM W OF THE 
SURFACE LOW. MODERATE EASTERLY SHEAR IS FORECAST TO REMAIN OVER 
THE SYSTEM THE NEXT DAY OR TWO...AND GLOBAL MODELS DO NOT FAVOR 
TROPICAL CYCLONE FORMATION.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG AXIS 09N84W TO 09N110W TO 11N122W TO 
09N140W. SCATTERED MODERATE CONVECTION FROM 180 TO 360 NM S OF 
AXIS BETWEEN 87W AND 90W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WITHIN 210 NM N OF AXIS BETWEEN 122W AND 126W. 
SCATTERED LIGHT CONVECTION WITHIN 120 NM N AND 180 NM S OF AXIS 
BETWEEN 132W AND 140W.

...DISCUSSION...

THE DISTURBED WEATHER AREA OFFSHORE THE SOUTH COAST OF MEXICO 
HAS SEPARATED INTO TWO DISTINCT FEATURES DURING THE PAST 12 TO 
24 HOURS. ONE OF THESE FEATURES IS DISCUSSED ABOVE IN THE 
SPECIAL FEATURES SECTION. THE OTHER IS A WELL-DEFINED LOW-LEVEL 
CIRCULATION CENTERED NEAR 15N96W...WHICH IS DRIFTING WEST. CIMSS 
SATELLITE ANALYSES SHOW ABOUT 20 KT OF EASTERLY SHEAR OVER THE 
SYSTEM...WHICH HAS HELPED TO DISPLACE AN EARLIER BURST OF DEEP 
CONVECTION WELL TO THE W OF THE LOW-LEVEL CENTER. EARLIER 
QUIKSCAT DATA INDICATED 20 TO 25 KT WINDS...WHICH LIKELY STILL 
EXIST THANKS TO INTERMITTENT BURSTS OF CONVECTION. SEAS NEAR THE 
LOW MAY BE AS HIGH AS 8 OR 9 FT.

OTHERWISE...FRESH LONG PERIOD NW TO N SWELL HAS BEGUN ARRIVING 
OVER THE FAR NORTHERN WATERS N OF 26N E OF 118W AND IS 
COINCIDENT WITH NW TO N 20 KT WINDS. THESE WINDS ARE EXPECTED TO 
TAPER OFF AND WAVE HEIGHTS SHOULD DROP BELOW 8 FT WITHIN 18 
HOURS. TO THE SOUTH...SW SWELL CONTINUES UNABATED OVER THE 
TROPICAL EAST PACIFIC AND MODELS INDICATE A NEW SURGE OF LOW 
PERIOD SW SWELL BY TUE OR WED.

$$
KIMBERLAIN