000
AXPZ20 KNHC 041603
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT OCT 04 2008

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1445 UTC.

...SPECIAL FEATURES...
HURRICANE MARIE AT 18.4N 122.1 W AT 04/1500 UTC OR ABOUT 845 NM 
W-SW OF SRN TIP OF BAJA CALIFORNIA DRIFTING N OR 360 DEG AT 2 
KT.  ESTIMATED MINIMUM CENTRAL PRES 987 MB AND MAXIMUM SUSTAINED 
WIND SPEED 65 GUSTS TO 80 KT.  REFER TO LATEST NHC FORECAST/ 
ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC AND 
INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP4/ 
WTPZ34 KNHC FOR MORE DETAILS.  CONVECTIVE ORGANIZATION OF MARIE 
HAS BECOME LESS IMPRESSIVE AS MARIE ENTERS LESS FAVORABLE UPPER 
LEVEL ENVIRONMENT WITH INCREASING WESTERLY SHEAR.  MARIE APPEARS 
TO HAVE PEAKED AS COOLER SEA SURFACE TEMPERATURES COOL AND AIR 
MASS BECOMES MORE STABLE AND DRIER.  CLOUD TOP TEMPERATURES HAVE 
WARMED AND MARIE SHOULD NOT REMAIN A HURRICANE FOR LONG.

TROPICAL DEPRESSION FIFTEEN-E STATIONARY AT 14.0N 99.5W AT 
04/1500 UTC OR ABOUT 200 NM S OF ACAPULCO MEXICO DRIFTING W AT  
2 KT.  ESTIMATED MINIMUM CENTRAL PRES 1006 MB AND MAXIMUM 
SUSTAINED WIND SPEED 30 GUSTS TO 40 KT.  REFER TO LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC 
AND INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCPEP5/WTPZ35 KNHC FOR MORE DETAILS.  MODERATE EASTERLY WIND 
SHEAR ARRESTING DEVELOPMENT OF T.D. 15-E EXPECTED TO LESSEN 
WHILE UPPER FLOW BECOMES MORE DIFFLUENT ENHANCING CHANCES OF 
INTENSIFICATION.  SEA SURFACE TEMPERATURES REMAIN FAVORABLE AND 
SYSTEM SHOULD INTENSIFY INTO TROPICAL STORM WITHIN THE NEXT 
24-36 HRS.

...TROPICAL WAVES...
NONE.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 09N84W TO 14N99W TO 09N105W TO 
18N122W TO 10N130W TO 09N140W. NUMEROUS STRONG CONVECTION WITHIN 
120 NM N AND 150 NM S OF AXIS BETWEEN 84W AND 94W. ISOLATED 
SCATTERED CONVECTION WITHIN 240 NM S OF AXIS BETWEEN 101W AND 
110W. SCATTERED MODERATE CONVECTION WITHIN 120 NM N AND 60 NM S 
OF AXIS BETWEEN 127W AND 134W AND WITHIN 90 NM N OF AXIS BETWEEN 
138W AND 140W.

...DISCUSSION...
UPPER LEVELS...
COMPLEX RIDGE WITH DOUBLE CENTER EXTEND FROM SW N ATLC ACROSS 
YUCATAN PENINSULA INTO E PAC WITH WESTERNMOST FOCI AT 18N114W 
WITH WEAK TROUGH ALONG CENTRAL MEXICO REACHING 10N105W. IT IS 
THE DIFFLUENT FLOW CAUSED BY THIS TROUGH WHICH IS EXPECTED TO 
FUEL T.D. 15-E INTENSIFICATION.  AT THE SAME TIME...HURRICANE    
MARIE IS MOVING AWAY FROM ITS FAVORABLE ENVIRONMENT ALOFT 
CURTAILING ITS CHANCES OF MAINTAINING ITS INTENSITY.

FURTHER W...TROUGH FROM CENTRAL BAJA CALIFORNIA TO 21N130W TO 
26N140W CAUSING MODERATE TO STRONG SUBSIDING AIR MASS N OF 16N
W OF 124W.  THIS DRY AND STABLE AIR MASS ALSO HELP IN CURTAILING 
HURRICANE MARIE DEVELOPMENT.  

ELSEWHERE AT THE SURFACE...
LOW PRES CENTER 1007 MB AT 10N88W DRIFTING W SHOWS AN IMPRESSIVE 
CLOUD PATTERN DESPITE MODERATE NORTHEASTERLY WIND SHEAR ALOFT.  
DOWNSTREAM ENVIRONMENT NOT COMPLETELY ADVERSE...SO POSSIBILITY 
OF GRADUAL AND SLOW INTENSIFICATION IS LIKELY BEFORE REACHING 
MORE FAVORABLE CONDITIONS WITHIN NEXT 36-48 HRS.  CONVECTION 
BANDS ARE INCREASING IN COVERAGE...CYCLONIC ORGANIZATION AND 
INTENSITY WITHIN 240 NM W AND 150 NM E SEMICIRCLES. 

STRONG WINDS BLOWING ACROSS ISTHMUS OF TEHUANTEPEC INTO E PAC 
HAVE BEEN SUPPORTED BY WEAK SURFACE LOW PRES 1010 MB OVER E 
COAST OF YUCATAN PENINSULA.  LOW PRES EXPECTED TO DRIFT NE ALONG 
STATIONARY FRONTAL BOUNDARY RELAXING PRES GRADIENT OVER SRN GULF 
OF MEXICO AND THEREFORE DIMINISHING TEHUANTEPEC WINDS WITHIN 
NEXT 36 HRS.

COLD FRONT AND ATTENDANT 1024 MB HIGH PRES CENTER PRODUCING 
LARGE LONG PERIOD SWELLS SPILLING SE INTO E PAC BASIN EVENTUALLY 
MERGING WITH SWELLS PRODUCED BY HURRICANE MARIE CAUSING VERY 
CONFUSED SEAS N OF 22N W OF 120W.  SWELL CONTINUE EXTENDING 
SOUTHWARD THROUGH FORECAST PERIOD. 

FINALLY...SIGNIFICANT LONG PERIOD CROSS-EQUATORIAL S SWELL 
CONTINUE S OF 15N W OF 130W WITH SEAS UP TO 12 FT.  NOAA WW3 
SOLUTION INDICATE SUBSIDING SEAS WITHIN 24-36 HRS BUT THEN 
BECOME REINFORCED BY NORTHERLY SWELL MENTIONED IN ABOVE 
PARAGRAPH.

$$
WALLY BARNES