000
AXPZ20 KNHC 070326
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE OCT 07 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...
HURRICANE NORBERT AT 14.7N 105.9W AT 07/0300 UTC OR 280 NM 
SOUTH-SOUTHWEST OF MANZANILLO MEXICO MOVING W-NW OR 285 DEG AT 
7 KT.  ESTIMATED MINIMUM CENTRAL PRES 987 MB.  MAXIMUM SUSTAINED 
WIND SPEED 65 WITH GUSTS TO 80 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.  NORBERT CONTINUE 
SHOWING SIGNS OF INTENSIFICATION AND HAS REACHED HURRICANE 
STRENGTH. CLOUD BANDS LENGTH AND CURVATURE INDICATE WELL 
ORGANIZED CYCLONE.  UPPER LEVEL OUTFLOW IS MOSTLY IN THE 
NORTHWEST SEMICIRCLE. NORBERT TRACK AND INTENSITY HAS NOT BEEN 
FORECAST WELL BY THE GFS MODEL. SOUTHWESTWARD DIGGING UPPER 
LEVEL TROUGH WILL INFLUENCE NORBERT TO TAKE A MORE NORTHERLY 
TRACK...APPROACHING THE COAST AND COOLER WATERS LATE FRIDAY.
 
LOW 12N89W 1008 MB IS NEARLY STATIONARY. LOW IS FORECAST TO MOVE 
SLOWLY WEST-NORTHWEST AND POSSIBLY BECOME A TROPICAL CYCLONE. 
THE GFS HAS INDICATED DEVELOPMENT FOR THE LAST SEVERAL DAYS AND 
THE SYSTEM HAS NOT DEVELOPED...IT CAN BE CONCLUDED THE MODEL IS 
NOT FORECASTING THIS SYSTEM WELL. NORTHEAST TO EAST UPPER FLOW 
IS PRODUCING SHEAR OVER THE SYSTEM AND ANY CONVECTION THAT HAS 
BEEN DEVELOPING NEAR THE CENTER IS MOVING WEST OF THE CENTER AND 
WEAKENING. WITH ITS DEEP CONVECTION GONE...CLOUD TOPS WARMED AND 
DISTURBED OUTFLOW...CHANCES OF INTENSIFICATION BECOME LESS 
PROBABLE.

...ITCZ...
ITCZ AXIS ALONG THE LINE...06N77W TO 09N100W TO 06N115W TO 
08N140W. SCATTERED MODERATE CONVECTION IS WITHIN 40 NM EITHER 
SIDE OF THE ITCZ AXIS FROM 98W TO 112W.

...DISCUSSION...
LOW...REMNANT OF MARIE...NEAR 19N124W 1008 MB MOVE WSW 10 KT.  
MAXIMUM SUSTAINED WIND SPEED 25 WITH GUSTS TO 35 KT. LAST NHC 
FORECAST/ADVISORY WAS ISSUED AT 2100Z OCT 06. ISOLATED 
CONVECTION IS NEAR THE CENTER BUT COOL SEA SURFACE TEMPERATURES 
WITH A DRIER AND STABLE AIR MASS WILL KEEP THE SYSTEM FROM 
DEVELOPING. MARIE SHOULD CONTINUE TO MOVE WSW AND CONTINUE TO 
SLOWLY WEAKEN.

UPPER LEVELS...
WEAK TROUGH IS OVER THE AREA EAST OF 115W. THE STRONGEST PART OF 
THE TROUGH IS OVER MEXICO NORTH OF 25N AND A STRONG SHORTWAVE IS 
NOTED OVER TEXAS. OTHER THAN THE MIDDLE AND UPPER LEVELS OF 
MARIE A WEAK RIDGE IS WEST OF 115W WITH A CENTER NEAR 30N130W. 

MIDDLE AND UPPER LEVEL MOISTURE FROM NORBERT IS BEING ADVECTED 
NORTHEASTWARD OVER CENTRAL MEXICO AND BEYOND OVER THE GULF OF 
MEXICO. ONLY THIN HIGH CLOUDS ARE ASSOCIATED WITH THIS MOISTURE.

DRY AND STABLE SUBSIDING AIR MASS OVER E PAC WEST OF THE 
MOISTURE PLUME FROM NORBERT. ONLY A FEW SCATTERED HIGH CLOUDS 
ARE OVER THE NORTHWEST PART OF THE AREA WEST OF THE NORBERT 
OUTFLOW AND WEST OF 117W. 

SURFACE...
EXCEPT FOR THE REMNANTS OF MARIE A WEAK RIDGE IS NORTHWEST OF A 
LINE FROM NORTHERN BAJA CALIFORNIA NEAR 32N117W TO 12N140W. 
ELSEWHERE EXCEPT FOR THE TROPICAL SYSTEMS A BROAD TROUGH IS 
ANALYZED.

NW SWELL IS AFFECTING THE NORTHWEST QUARTER OF THE AREA. THE 
SWELL SHOULD SUBSIDE TO LESS THAN 8 FT IN 48 HOURS. ANOTHER AREA 
OF SWELL IS SOUTH OF 20N FROM 92W TO 115W...THIS SWELL IS FROM 
THE FAR SOUTH PACIFIC AND IT WILL CONTINUE THROUGH 48 HOURS 
ALTHOUGH DIMINISH IN COVERAGE.

$$
LL