000
AXPZ20 KNHC 202101
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC TUE OCT 20 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...

THE BREAKDOWN OF THE CENTRAL AMERICAN GYRE HAS HELPED FOR ENERGY 
TO CONSOLIDATE AROUND THE LOW PRESSURE AREA WHICH FORMED SE OF 
THE GULF OF TEHUANTEPEC. THE LOW DEVELOPED INTO A TROPICAL 
DEPRESSION THIS MORNING. TROPICAL DEPRESSION 20-E WAS LOCATED 
NEAR 13.2N 94.8W AT 2100 UTC MOVING WEST OR 265 DEGREES AT 3 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE WAS 1006 MB. MAXIMUM 
SUSTAINED WIND SPEED WAS 30 KT WITH GUSTS TO 40 KT. NUMEROUS 
MODERATE TO STRONG CONVECTION WAS NOTED WITHIN 180 NM E 
QUADRANT. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS 
NOTED ELSEWHERE WITHIN 90 NM OF CENTER. THE DEPRESSION IS 
FORECAST TO INTENSIFY AS THE SYSTEM MOVES WESTWARD REACHING 
TROPICAL STORM STRENGTH TONIGHT. THE SYSTEM IS FORECAST TO 
CONTINUE TO INTENSIFY REACHING HURRICANE STRENGTH THURSDAY. 
HEAVY RAIN AND FLOODING IS POSSIBLE OVER SOUTHERN MEXICO THE 
NEXT COUPLE OF DAYS IN ASSOCIATION TO THIS SYSTEM. PLEASE SEE 
LATEST FORECAST AND PUBLIC ADVISORIES ISSUED BY THE NATIONAL 
HURRICANE CENTER UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC 
FOR MORE DETAILS.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
THE MONSOON TROUGH EXTENDS FROM TROPICAL DEPRESSION TWENTY-E TO 
10N103W TO 11N112W TO 07N126W. SCATTERED MODERATE ISOLATED 
STRONG CONVECTION WAS NOTED WITHIN 150 NM S OF THE MONSOON 
TROUGH BETWEEN 95W AND 112W. SCATTERED MODERATE CONVECTION WAS 
NOTED WITHIN 30 NM N AND 90 NM S OF THE MONSOON TROUGH BETWEEN 
116W AND 125W. 

...DISCUSSION... 

HURRICANE OLAF CONTINUES TO MOVE FURTHER FROM THE AREA. WINDS 
AND SEAS CONTINUE TO DECREASE OVER THE FAR WESTERN WATERS. 
TROPICAL STORM WINDS HAVE SHIFTED W OF THE AREA. WINDS TO 30 KT 
COVER THE AREA OVER FORECAST WATERS FROM 06N TO 13N W OF 135W 
WITH SEAS OF 13 FT. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WAS NOTED OVER FORECAST WATERS FROM 05N TO 13N W OF 
136W. RELATED TO OLAF. WINDS AND SEAS WILL CONTINUE TO DECREASE 
OVER THE WESTERN FORECAST WATERS AS OLAF MOVES FURTHER FROM THE 
AREA. BY THU AFTERNOON WINDS WILL FALL TO 20 KT OR LESS. WITH 
SEAS OF 11 FT COVERING THE AREA W OF LINE FROM 26N140W TO 
20N137W TO 14N137W TO 10N140W.

A 1028 MB SUBTROPICAL HIGH PRESSURE CENTER NEAR 35N138W EXTENDS 
A RIDGE AXIS SOUTHEASTWARD TO NEAR 18N112W. THE PRESSURE 
GRADIENT BETWEEN THE RIDGE AND LOWER PRESSURE OVER THE SW UNITED 
STATES IS PRODUCING FRESH TO STRONG NW WINDS OFF THE COAST OF 
SOUTHERN CALIFORNIA. NW SWELL ASSOCIATED WITH THESE WINDS IS 
PROPAGATING INTO NORTHEASTERN WATERS N OF 28N BETWEEN 116W AND 
124W WITH SEAS IN THE 7-9 FT RANGE. THE WINDS N OF THE AREA WILL 
DIMINISH TONIGHT AND THE SWELL WILL SUBSIDE TO 6-7 FT OVER 
FORECAST WATERS BY WED AFTERNOON.
                                                    
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AL