000
AXPZ20 KNHC 192205
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.               

...SPECIAL FEATURES...

A COUPLE OF LOW PRESSURE CENTERS ARE EMBEDDED WITHIN THE MONSOON 
TROUGH...ONE LOCATED NEAR 19N111.5W AND THE OTHER NEAR 14N118W. 
SCATTERED STRONG CONVECTION HAS DEVELOPED WITHIN 270 NM NW AND 
240 NM SW QUADRANTS OF THE LOW NEAR 19N111.5W...WHILE SCATTERED 
MODERATE TO STRONG CONVECTION HAS DEVELOPING ACROSS THE SOUTHERN 
GULF OF CALIFORNIA FROM 21.5N TO 26N. 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 IS INVOF 90W...EXTENDING FROM BELIZE S-SW ACROSS 
CENTRAL AMERICA TO ALONG ABOUT 90W ACROSS THE PACIFIC. SCATTERED 
MODERATE TO STRONG CONVECTION ASSOCIATED WITH THIS WAVE HAS 
DEVELOPED ACROSS THE YUCATAN PENINSULA AHEAD OF THIS WAVE...AS 
WELL AS CENTRAL AMERICA NEAR THE WAVE AXIS...WHILE ISOLATED 
MODERATE CONVECTION WAS NOTED FROM 10N TO 13.5N BETWEEN 91W AND 
93.5W.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 10N74W TO 10.5N99W 
TO 09N111W...WHERE IT REMAINS FRACTURED...THEN RESUMES FROM 
COMPLEX LOW PRES NEAR 19N111.5W TO LOW PRES NEAR 14N118W TO 
BEYOND 11N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 180 NM 
S OF TROUGH BETWEEN 81W AND 84W. SCATTERED MODERATE TO STRONG 
WITHIN 210 NM N AND 330 NM S OF TROUGH BETWEEN 97W AND 111W. 
SCATTERED TO LOCALLY NUMEROUS MODERATE TO STRONG WITHIN 90 NM N 
AND 120 NM S OF TROUGH BETWEEN 113W AND 123W. SCATTERED MODERATE 
TO STRONG WITHIN 240 NM S OF TROUGH BETWEEN 125W AND 140W. 
 
...DISCUSSION...

A 1024 MB HIGH IS CENTERED NW OF THE AREA NEAR 37N145W AND 
EXTENDS A RIDGE SE TO NEAR 26N114W. THE PRES GRADIENT BETWEEN 
THE RIDGE AND MONSOON TROUGH IS PRODUCING MODERATE TO FRESH NE 
TRADE WINDS OVER THE WESTERN WATERS. THIS IS PRODUCING SEAS TO 8 
FT FROM FROM 17N TO 24N W OF 130W. THE HIGH PRESSURE CENTER WILL 
SHIFT FURTHER FROM THE AREA OVER THE NEXT 24 HOURS WHICH WILL 
LOOSEN THE PRESSURE GRADIENT AND DIMINISH TRADE WINDS MODESTLY 
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 AND PULSE EACH NIGHT TO 25 
KT...POSSIBLY 30 KT...THROUGH TUESDAY NIGHT. 
 
$$
STRIPLING