000
AXPZ20 KNHC 062201
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE APR 06 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2030 UTC.

...ITCZ...

AXIS WAS ANALYZED ALONG 06N76W TO 05N79W TO 06N90W TO 04N100W TO 
08N113W TO 04N140W. SCATTERED MODERATE TO STRONG CONVECTION WAS 
OCCURRING WITHIN 120 NM N AND 90 NM S OF AXIS E OF 84W... 
BETWEEN 94W AND 103W...AND WITHIN 90 NM N AND 120 NM S OF AXIS W 
OF 115W.  

...DISCUSSION...

A LONG WAVE TROUGH-RIDGE-TROUGH PATTERN COVERS THE EPAC N OF 18N 
AND E OF 170W. A BROAD UPPER RIDE WAS CENTERED ALONG 138W N OF 
28N...WHILE DOWNSTREAM A BROAD UPPER TROUGH ACROSS THE GREAT 
PLAINS OF THE U.S. EXTENDED SOUTH INTO THE 4 CORNERS REGION THEN 
TRAILED SW AS A NARROW TUTT LIKE AXIS UNDER THE RIDGE TO A 
MIDDLE TO UPPER LEVEL LOW NEAR 25N140W. A S/W RIDGE TO THE W OF 
THIS LOW WAS MOVING EWD AND FORCING THE MID-UPPER LOW EWD IN 
TANDEM. WESTERLIES ALOFT DOMINATED MUCH OF THE AREA SOUTH OF 
THESE FEATURES...WITH A TROPICAL JET EXTENDING FROM NEAR 13N136W 
TO THE S HALF OF BAJA CALIFORNIA AND ACROSS THE NORTH HALF OF 
MEXICO. ACROSS THE DEEP TROPICS...ACTIVE CONVECTION ALONG THE 
ITCZ WAS MAINTAINING UPPER LEVEL RIDGING ALONG ABOUT 08N BETWEEN 
95W AND 145W.

A BROAD SURFACE RIDGE WAS CENTERED ON A 1033 MB HIGH NEAR 
35N138W AND COVERED MUCH OF THE AREA N OF THE ITCZ W OF 110W. 
THE PRESSURE GRADIENT BETWEEN THIS SURFACE HIGH AND THE ITCZ WAS 
MAINTAINING A LARGE AREA OF FRESH TO STRONG TRADES FROM 06N TO 
23N W OF 120W. A TIGHT PRES GRADIENT BETWEEN THE AFOREMENTIONED 
HIGH PRESSURE AND TROUGHING OVER THE SIERRA MADRE OCCIDENTALES 
WAS RESULTING IN NW TO N WINDS OF 20-25 KT N OF 22N E OF 
120W...AND WAS BEGINNING TO INCREASE WINDS TO NEAR THESE VALUES 
OVER THE GULF OF CALIFORNIA N OF 26N. WINDS IN THE GULF OF 
CALIFORNIA ARE EXPECTED TO REMAIN NEAR 20-25 KT WITH 
NOCTURNAL/DIURNAL INDUCED FLUCTUATIONS THROUGH WED NIGHT BEFORE 
DROPPING BELOW 20 KT THU. A FRONTAL SYSTEM MOVING MOVING INTO 
THE NE PACIFIC WED WILL CAUSE THE ABOVE HIGH TO WEAKEN BRIEFLY 
WED BEFORE BEING REINFORCED BY A 1041 MB HIGH THU...AND 
REINVIGORATING THE TRADES N OF THE ITCZ.

WAVEWATCH MODEL GUIDANCE INDICATES THE MOST RESENT PULSE OF 
LARGE NW SWELL HAS REACHED THE EQUATOR THIS AFTERNOON...AND WILL 
BEGIN TO GRADUALLY FADE ACROSS THE AREA WATERS WED THROUGH THU. 
COMBINED SEAS OF 12 TO 15 FT ARE FOUND N OF 24N AND W OF BAJA 
THIS AFTERNOON AND WILL PERSIST THROUGH LATE TONIGHT BEFORE 
SUBSIDING VERY SLOWLY. E OF 125W...THESE LONG PERIOD NW SWELL 
WILL MERGE WITH LONG PERIOD SRN HEMI SWELL FROM THE SW THROUGH 
THU TO MAINTAIN COMBINED SEAS OF 8 TO 11 FT ACROSS THE DEEP 
TROPICS W OF 100W. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$

STRIPLING