000
AXPZ20 KNHC 191607
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT MAY 19 2007

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 
1545 UTC.

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 7N77W 7N105W 
9N115W 8N130W 7N140W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION IS WITHIN 200NM N AND 60NM S OF THE AXIS BETWEEN 
84W-97W. SIMILAR ACTIVITY IS WITHIN 150NM EITHER SIDE OF THE 
AXIS BETWEEN 100W-111W. SCATTERED MODERATE IS WITHIN 120NM OF 
THE AXIS BETWEEN 119W-123W...AND BETWEEN 128W-130W.

...DISCUSSION...
A QUASI STATIONARY 1027MB SFC HIGH NEAR 30N136W DOMINATES MUCH 
OF THE DISCUSSION AREA W OF 110W. THIS IS PRODUCING MODERATE TO 
FRESH TRADES ESPECIALLY FROM 10N-20N W OF 125W. THE GRADIENT 
ALSO REMAINS SQUEEZED A BIT E OF THE HIGH AND W OF NORTHERN 
BAJA...AS THE RIDGING INTERACTS WITH INVERTED TROUGHING THROUGH 
THE GULF OF CALIFORNIA. THIS WILL CONTINUE TO PRODUCE AN AREA OF 
~20KT N TO NW WINDS AND 7-10 FT SHORT PERIOD N/NW SWELL IN THE 
AREA N OF 22N BETWEEN 115W AND 127W OVER THE NEXT COUPLE OF 
DAYS. OVERCAST LOW CLOUDS WITH THE MARINE LAYER ON THE E SIDE OF 
THE HIGH ARE BANKING UP AGAINST THE COAST OF N AND CENTRAL 
BAJA...BUT SHOULD THIN A BIT THROUGH LATE AFTERNOON. 

THIS MORNINGS QUIKSCAT PASS UNFORTUNATELY MISSED THE GULF OF 
TEHUANTEPEC. HOWEVER...WINDS AT IXTEPEC MEXICO NEAR THE EXIT 
REGION OF THE CHIVELA PASS HAVE BEEN SUSTAINED NEAR 20 KT 
OVER THE LAST FEW HOURS. THIS LEADS ME TO BELIEVE THE WINDS ARE 
A BIT HIGHER FURTHER DOWNSTREAM IN THE ADJACENT EPAC WATERS. 
BOTH THE NAM AND GFS SEEMED TO HAVE THIS INITIALIZED FAIRLY 
WELL...BUT DIVERGE IN THE FORECAST OVER THE NEXT COUPLE OF DAYS. 
HAVE OPTED TO LEAN TOWARDS THE SLIGHTLY MORE AGGRESSIVE NAM 10M 
SOLUTION GIVEN ITS TRACK RECORD OVER THE LAST FEW DAYS...AND FOR 
ITS OVERALL PERFORMANCE OVER THE RECENT COOL SEASON IN 
GENERAL. HAVE GONE AGAINST ISSUING A GALE WARNING FOR THIS AS 
THE DIURNAL INFLUENCE WILL ALLOW PERIODS OF LIGHTER WINDS DURING 
THE EARLY EVENING HOURS. HOWEVER...IF THE NAM HOLDS TRUE A FEW 
GUSTS TO GALE ARE NOT OUT THE QUESTION TOMORROW MORNING. 

SW FLOW BETWEEN A SHORTWAVE UPPER TROUGH OFF NRN BAJA/SRN 
CALIFORNIA AND AN UPPER HIGH NEAR 12N112W IS SPREADING UPPER 
MOISTURE OVER THE ITCZ THROUGH CENTRAL MEXICO. THE ENTRANCE 
REGION OF THE ASSOCIATED JET SEEMS TO BE ENHANCING A LITTLE BIT 
OF CYCLONIC TURNING IN THE LOWER TO MID LEVELS NEAR 10N123W. 

$$
WILLIS