000
AXPZ20 KNHC 080939
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON SEP 08 2008

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 
0730 UTC.

...SPECIAL FEATURES...

TROPICAL STORM LOWELL IS CENTERED NEAR 18.2N 110.6W...OR ABOUT 
290 NM S OF THE SOUTHERN TIP OF THE BAJA PENINSULA...MOVING WNW 
OR 290 DEG AT 9 KT. ESTIMATED CENTRAL PRESSURE IS 998 MB. 
MAXIMUM SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT. NUMEROUS 
MODERATE TO STRONG CONVECTION CAN BE FOUND WITHIN 210 NM SW 
SEMICIRCLE OF TROPICAL STORM LOWELL WITH SCATTERED MODERATE 
CONVECTION NOTED ELSEWHERE FROM 14N TO 20N BETWEEN 109W AND 
116W. THE SW SKEW TO THE CONVECTION ASSOCIATED WITH LOWELL IS 
DUE TO STRONG NE FLOW ALOFT THROUGH S MEXICO AND THE ADJACENT E 
PAC ON THE S EDGE OF A BROAD ANTICYCLONE. PLEASE REFER TO THE 
LATEST NHC PUBLIC ADVISORY UNDER AWIPS HEADER MIATCPEP3 OR WMO 
HEADER WTPZ33 KNHC AND THE FULL FORECAST ADVISORY UNDER AWIPS 
HEADER MIATCMEP3 OR WMO HEADER WTPZ23 KNHC FOR MORE DETAILS. 

...ITCZ...

ITCZ AXIS IS ALONG 07N78W 06N85W 12N110W 10N126W 07N140W. 
SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 150 NM N OF 
AXIS E OF 80W.  

...DISCUSSION...

SUBTROPICS...
AXIS OF A BROAD UPPER LEVEL ANTICYCLONE CAN BE FOUND BETWEEN 20N 
AND 25N OVER FORECAST WATERS. THIS REGION SEPARATES 20 TO 30 KT 
E WINDS ALOFT S OF 20N AND 50 KT W WINDS ALOFT N OF 30N OVER THE 
SW CONUS AND ADJACENT E PAC. WEAK YET DIFFLUENT FLOW OVER THE 
MOUTH OF THE GULF OF CALIFORNIA IS HELPING TO LIFT THE TROPICAL 
MOISTURE TRANSPORTED N WITHIN THE SOUTHERLY LOW LEVEL FLOW ON 
THE E SIDE OF TROPICAL STORM LOWELL. AS A RESULT...NUMEROUS 
MODERATE CONVECTION CAN CURRENTLY BE FOUND BETWEEN 20N AND 25N E 
OF 108W TO THE MEXICAN COAST. MEANWHILE...THE UPPER LEVEL 
TROUGHING N OF THIS ANTICYCLONE IS FORECAST TO AMPLIFY OVER N 
WATERS BETWEEN 120W AND 125W BY TUE. THIS TROUGHING SHOULD HELP 
STEER TROPICAL STORM LOWELL N AND NE TUE AND BEYOND AND DIVIDE 
THE BROAD ANTICYCLONE IN TWO.

TROPICS...
SOUTHERN HEMISPHERE SWELL EVENT CONTINUES OVER TROPICAL WATERS 
GENERALLY BETWEEN 100W AND 125W...WITH SEAS FURTHER ELEVATED DUE 
TO INCREASED PRESSURE GRADIENT...AND HENCE WINDS...S OF LOWELL. 
ELSEWHERE...MAINLY NE TO E MID TO UPPER LEVEL FLOW ON THE 
SOUTHERN PERIPHERY OF A SUBTROPICAL RIDGE DOMINATES THE TROPICS. 
A CONSIDERABLE AMOUNT OF MOISTURE IS LOCATED E OF 115W BUT DEEP 
CONVECTION REMAINS CONFINED TO REGION NEAR TROPICAL STORM LOWELL 
AND FAR E PORTION OF THE ITCZ...WITH CONFLUENT FLOW INHIBITING 
CONVECTION IN THE VICINITY OF THE LINE FROM 05N110 NE TOWARD THE 
COAST OF GUATEMALA.

$$
SCHAUER CLARK