000
AXPZ20 KNHC 151558
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU MAY 15 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 
1530 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 07N78W TO 10N91W TO 10N108W TO 
04N123W TO 03N140W. SCATTERED MODERATE ISOLATED STRONG FROM 03N 
TO 11N E OF 110W. 

...DISCUSSION...

SUBTROPICAL PACIFIC...
AN UPPER LEVEL TROUGH EXTENDS FROM SW NEW MEXICO SW TO THE 
SOUTHERN TIP OF BAJA CALIFORNIA THEN EXTENDS WNW AS A SHEAR 
AXIS. A CUTOFF LOW IS LOCATED NEAR 22N140W AT THIS TIME. 
DIFFLUENT FLOW ALOFT E OF THIS LOW IS SUPPORTING A BROAD AREA OF 
WIDELY SCATTERED CONVECTION. A HIGH AMPLITUDE UPPER RIDGE 
EXTENDS ALONG 125W TO AN UPPER ANTICYCLONIC CENTER N OF THE 
AREA. THE TROUGH EMANATING FROM THE SOUTHWESTERN CONUS WILL 
CONTINUE TO PULL MOISTURE NORTHWARD TOWARD THE GULF OF 
CALIFORNIA AND WEST CENTRAL MEXICO OVER THE NEXT COUPLE OF DAYS 
AS IT CONTINUES TO AMPLIFY. THIS MOISTURE WILL RETREAT FURTHER S 
THIS WEEKEND AS THE TROUGH SWINGS FURTHER TO THE EAST. AT THE 
SURFACE...A RIDGE DOMINATES THE REGION WITH THE AXIS EXTENDING 
THROUGH 30136W SW TO 19N151W. THIS SURFACE RIDGE IS EXPECTED TO 
WEAKEN OVER THE NEXT COUPLE OF DAYS REDUCING THE TRADE WINDS W 
OF 125W.

TROPICAL PACIFIC...
A BROAD UPPER RIDGE CONNECTING TWO ANTICYCLONIC CENTERS...ONE 
NEAR 12N118W AND THE OTHER JUST E OF THE YUCATAN 
PENINSULA...COVERS THE AREA E OF 130W. E OF 110W THE UPPER RIDGE 
IS ENHANCING CONVECTION ASSOCIATED WITH THE ITCZ. A DEEP-LAYERED 
TROUGH S OF 13N AND CENTERED ALONG 117W IS ALSO SPAWNING 
CONVECTION.   

PLEASE NOTE...TODAY MARKS THE BEGINNING OF THE EASTERN PACIFIC 
HURRICANE SEASON...WHICH RUNS UNTIL NOVEMBER 30.  BASED ON DATA 
FROM 1971-2005...15-16 NAMED STORMS FORM ON AVERAGE...9 OF WHICH 
BECOME HURRICANES AND 4-5 OF THOSE BECOMING MAJOR HURRICANES 
(CATEGORY 3 OR GREATER ON THE SAFFIR-SIMPSON SCALE). BUT PLEASE 
REMEMBER THAT THIS HAS NO CORRELATION TO THE NUMBER OF SYSTEMS 
THAT MAY MAKE LANDFALL ALONG THE COAST OF MEXICO OR CENTRAL 
AMERICA.

$$
BELL/BERG