000
AXPZ20 KNHC 070351
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED APR 07 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0215 UTC.

...ITCZ...
AXIS ANALYZED ALONG 05N77W TO 
06N95W TO 04N101W TO 09N114W TO 04N129W TO 04N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS OCCURRING WITHIN 90 NM N 
AND 150 NM S OF AXIS BETWEEN 86W AND 105W...AND ALSO WITHIN 120 
NM N AND 240 NM S OF AXIS BETWEEN 112W AND 120W...AND WITHIN 90 
NM EITHER SIDE OF AXIS W OF 127W.

...DISCUSSION...

A LONG WAVE TROUGH-RIDGE-TROUGH PATTERN COVERS THE EPAC N OF 18N 
AND E OF 165W. A BROAD UPPER RIDGE WAS CENTERED ALONG 136W 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 25N139W. 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 15N136W 
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 
93W AND 145W. CONVECTION NEAR THE ITCZ IS EXPECTED TO REMAIN 
ACTIVE W OF 100W THROUGH THE PERIOD.

A BROAD SURFACE RIDGE WAS CENTERED ON A 1032 MB HIGH NEAR 
36N136W 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 
22N W OF 122W. 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 
122W...AND HAS BEGUN TO INCREASE WINDS TO NEAR THESE VALUES 
THROUGH THE GULF OF CALIFORNIA N OF 25N...WHERE SEAS ARE 
BUILDING TO 6 FT AND GREATER. 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 RECENT PULSE OF 
LARGE NW SWELL REACHED THE EQUATOR THIS AFTERNOON...AND WILL 
BEGIN TO GRADUALLY FADE ACROSS THE AREA WATERS WED THROUGH THU. 
COMBINED SEAS OF 12 TO 14 FT ARE FOUND N OF 24N AND E OF 134W TO 
BAJA THIS EVENING AND WILL PERSIST OVERNIGHT BEFORE SUBSIDING 
VERY SLOWLY WED AND THU. E OF 125W...THESE LONG PERIOD NW SWELLS 
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