000
AXPZ20 KNHC 211504
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC MON SEP 21 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...

TROPICAL DEPRESSION SIXTEEN-E...LOCATED OVER THE GULF OF 
CALIFORNIA NEAR 29.4N 112.1W 1002 MB AT 1500 UTC SEP 21 MOVING 
NNE OR 020 DEG AT 17 KT. MAXIMUM SUSTAINED WINDS 30 KT GUSTS 40 
KT. SATELLITE IMAGERY SHOWS A LARGE AREA OF SCATTERED STRONG 
CONVECTION NE OF THE CIRCULATION OVER THE NW SECTION OF 
MEXICO...PRIMARILY IN THE STATE OF SONORA MEXICO. THE DEPRESSION 
IS FORECAST TO MOVE INLAND ACROSS THE STATE OF SONORA MEXICO 
THIS AFTERNOON. THE MAIN HAZARD FROM THE DEPRESSION CONTINUES TO 
BE HEAVY RAINFALL THAT WILL OCCUR WITH AND WELL AHEAD OF THE 
DEPRESSION OVER BAJA NW MAINLAND MEXICO...ARIZONA AND NEW MEXICO 
THROUGH TUE. THESE RAINS COULD PRODUCE LIFE THREATENING FLASH 
FLOODS AND LEAD TO MUDSLIDES...ESPECIALLY ACROSS THE MOUNTAINOUS 
TERRAIN OF MEXICO.

SEAS ASSOCIATED TO THE DEPRESSION ARE IN THE 8-10 FT RANGE OVER 
THE GULF OF CALIFORNIA...ESPECIALLY BETWEEN 27W AND 30W. THESE 
CONDITIONS WILL DIMINISH STARTING THIS AFTERNOON AS THE 
DEPRESSION MOVES INLAND AND WINDS OVER THE GULF OF CALIFORNIA 
DECREASE. BY 24 HOURS...WITH THE DEPRESSION EXPECTED TO BE A 
REMNANT LOW WELL INLAND...WINDS OVER THE GULF OF CALIFORNIA ARE 
FORECAST TO BE 20 KT OR LESS WITH SEAS LESS THAN 8 FT.
 
...TROPICAL WAVES... 

TROPICAL WAVE AXIS IS NEAR 107W FROM 05N TO 18N...SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED FROM 05N TO 15N 
BETWEEN 103W AND 110W. 
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

THE MONSOON TROUGH EXTENDS FROM 08N77W TO 08N95W TO 10N100W 
WHERE IT REMAINS FRACTURED. IT RESUMES FROM 15N117W TO 12N127W 
TO 12N135W TO BEYOND 10N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WAS NOTED WITHIN 120 NM S OF THE MONSOON TROUGH E OF 
86W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED 
WITHIN 150 NM N OF THE MONSOON TROUGH BETWEEN 86W AND 100W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 
90 NM OF THE MONSOON TROUGH BETWEEN 121W AND 124W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 150 NM S OF 
THE MONSOON TROUGH BETWEEN 124W AND 131W. 
 
...DISCUSSION...

HIGH PRESSURE OF 1027 MB CENTERED WELL NW OF THE AREA NEAR 
37N153W EXTENDS A RIDGE SE TO NEAR 22N130W. THE PRES GRADIENT 
BETWEEN THE RIDGE AND MONSOON TROUGH IS PRODUCING MODERATE TO 
LOCALLY FRESH NE TRADE WINDS OVER WESTERN PORTIONS OF THE AREA W 
OR 127W. THIS IS RESULTING IN SEAS TO 8 FT FROM 14N TO 16N W OF 
138W. THE HIGH PRES CENTER WILL WEAKEN OVER THE NEXT 24 HOURS. 
WINDS AND SEAS WILL DECREASE WITH SEAS SUBSIDING BELOW 8 FT BY 
THIS EVENING.
 
GAP WINDS...A PULSING OF NORTHERLY FLOW HAS BEGUN ACROSS THE 
GULF OF TEHUANTEPEC. WINDS WILL PEAK DURING THE OVERNIGHT AND 
EARLY MORNING HOURS TO NEAR 30 KT TONIGHT AND TUE NIGHT. WINDS 
ARE THEN FORECAST TO DIMINISH TO 20 KT DURING TUE AFTERNOON WITH 
SEAS LOWERING TO AROUND 8 FT. 
 
$$
AL