000
AXPZ20 KNHC 191503
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC SAT SEP 19 2015

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM  
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.               

...SPECIAL FEATURES...

A COUPLE OF LOW PRESSURE CENTERS ARE EMBEDDED WITHIN THE MONSOON 
TROUGH...ONE LOCATED NEAR 18.5N112W AND THE OTHER NEAR 14N119W. 
SCATTERED STRONG CONVECTION HAS DEVELOPED WITHIN 120 NM W 
QUADRANT OF THE LOW NEAR 18.5N112W. THERE IS SOME POTENTIAL FOR 
THIS LOW TO DEVELOP INTO A TROPICAL CYCLONE AND THE LATEST 
FORECAST GIVES THIS SYSTEM A MEDIUM CHANCE FOR DEVELOPMENT AS IT 
MOVES IN A N-NW DIRECTION.

THE MONSOONAL FLOW WILL CONTINUE TO ADVECT ABUNDANT TROPICAL 
MOISTURE TOWARDS CENTRAL AND SOUTHERN BAJA CALIFORNIA AS WELL AS 
THE ADJACENT GULF AND MEXICAN STATES TO THE E. THE MOISTURE 
SHOULD THEN SPREAD FARTHER NW-N ACROSS NORTHERN BAJA CALIFORNIA. 
SOME OF THIS MOISTURE MAY REACH FAR SOUTHERN CALIFORNIA SUN INTO 
MON. INCREASING RAIN CHANCES SHOULD BE EXPECTED ACROSS THESE 
AREAS...EXTENDING INLAND ACROSS MAINLAND MEXICO TO THE W SLOPES 
OF THE SIERRA MADRES OCCIDENTALES...WITH THE POTENTIAL FOR HEAVY 
RAINS...FLASH FLOODING AND LANDSLIDES THROUGH THE WEEKEND. 

...TROPICAL WAVES... 

A TROPICAL WAVE AXIS IS NEAR 92W N OF 09N. SCATTERED MODERATE 
CONVECTION ASSOCIATED TO THIS WAVE WAS NOTED FROM 06N TO 11N 
BETWEEN 91W AND 95W.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

THE MONSOON TROUGH EXTENDS FROM 08N83W TO 09N94W TO 06N108W 
WHERE IT HAS FRACTURED. IT RESUMES FROM LOW PRES NEAR 18.5N112W 
TO 11N129W TO 11N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WAS NOTED WITHIN 180 NM S OF TROUGH BETWEEN 90W AND 
101W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED 
WITHIN 180 NM OF TROUGH BETWEEN 101W AND 108W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 180 NM S OF 
TROUGH BETWEEN 113W AND 128W. 
 
...DISCUSSION...

HIGH PRES CENTERED NW OF THE AREA NEAR 36N145W EXTENDS A RIDGE 
SE TO NEAR 22N118W. THE PRES GRADIENT BETWEEN THE RIDGE AND 
MONSOON TROUGH IS PRODUCING MODERATE TO FRESH TRADE WINDS OVER 
THE WESTERN WATERS. THIS IS PRODUCING SEAS TO 8 FT FROM FROM 18N 
TO 24N W OF 132W. THE HIGH PRESSURE CENTER WILL SHIFT FURTHER 
FROM THE AREA OVER THE NEXT 24 HOURS. THIS WILL LOOSEN THE 
GRADIENT AND DIMINISH WINDS OVER THIS AREA AND ASSOCIATED SEAS 
WILL SUBSIDE BELOW 8 FT.
 
GAP WINDS... N WINDS OF 20-25 KT ARE EXPECTED TO BEGIN ACROSS 
THE GULF OF TEHUANTEPEC EARLY ON MON.
 
$$
AL