000
AXPZ20 KNHC 181525
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
1605 UTC FRI OCT 18 2013

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.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           

THE MONSOON TROUGH EXTENDS FROM 09N84W THROUGH A LOW PRES NEAR 
10N93W TO 11N106W THROUGH A SECOND LOW PRES NEAR 09N112W TO 
08N118W TO A THIRD LOW PRES NEAR 11N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION FROM 08N TO 15N BETWEEN 94W AND 100W. 
NUMEROUS MODERATE SCATTERED STRONG CONVECTION IS WITHIN 90 NM 
EITHER SIDE OF THE TROUGH AXIS BETWEEN 108W AND 116W.

...DISCUSSION...                                              

1029 MB HIGH PRESSURE CENTERED WELL N OF THE AREA NEAR 48N135W. 
AN UNUSUALLY LARGE DISTANCE FROM THE HIGH TO LOW PRESSURE TROUGH 
ASSOCIATED WITH THE CONVERGENCE ZONE IS MAINTAINING A VERY WEAK 
PRESSURE GRADIENT OVER THE AREA. AS A RESULT...RELATIVELY BENIGN 
MARINE CONDITIONS PREVAIL OVER THE ENTIRE DISCUSSION AREA...WITH 
WIDESPREAD GENTLE TO MODERATE WINDS AND 4-6 FT SEAS.

THE SWIRL OF LOW CLOUDS ASSOCIATED WITH REMNANT LOW PRISCILLA 
IS CENTERED NEAR 19N126W. THE LOW IS EXPECTED TO WEAKEN INTO A 
TROUGH LATER TODAY. AN AREA OF LOW PRESSURE CENTERED NEAR 9N112W 
HAS BECOME BETTER ORGANIZED OVER THE PAST 12-24 HOURS. AN OSCAT 
PASS AT 0725 UTC SHOWED AN ELONGATED CYCLONIC CIRCULATION WITH 
15-20 KT S-SW WINDS SOUTH OF THE CIRCULATION CENTER. CONVECTION 
ASSOCIATED WITH THE LOW INCREASED SIGNIFICANTLY OVERNIGHT. MODEL 
GUIDANCE INDICATES THE LOW WILL DRIFT W THROUGH SUN WITH LITTLE 
CHANGE IN INTENSITY AND SEAS BUILDING TO 6-8 FT SE OF THE CENTER.

LOOKING AHEAD...LONG PERIOD NW SWELL ASSOCIATED WITH STRONG LOW 
PRES SYSTEM LOCATED NW OF AREA WILL SWEEP INTO NW WATERS SUN AND 
SPREAD SOUTHEASTWARD MON THROUGH WED. WAVE MODEL GUIDANCE SHOWS 
THE LEADING EDGE OF SWELL TRAIN WITH 22-23 SEC PERIOD...WHICH 
WILL PRODUCE UNUSUALLY LARGE SURF HEIGHTS AS IT REACHES SHALLOW 
WATER ALONG THE PACIFIC COAST NEXT WEEK.
 
$$ 
MUNDELL