000
AXPZ20 KNHC 050926
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED MAY 05 2010

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

AXIS ANALYZED ALONG 10N85W TO 04N96W TO 07N117W TO 04N129W TO 
05N140W. NO SIGNIFICANT CONVECTION WAS NOTED.

...DISCUSSION...

AN UPPER LEVEL RIDGE AXIS IS CENTERED JUST W OF THE AREA 
EXTENDING FROM JUST E OF HAWAII TO 32N148W. AN UPPER LEVEL 
TROUGH IS TO THE E OF THIS RIDGE AXIS EXTENDING FROM NW 
CALIFORNIA TO 32N133W TO 28N140W AND SW OF THE AREA. MID TO 
UPPER LEVEL MOISTURE IS BEING ADVECTED OUT AHEAD OF THE TROUGH. 
A WEAKENING UPPER LEVEL RIDGE EXTENDS FROM 32N127W TO 13N140W 
WHICH IS FLATTENING AS THE TROUGH TO THE W APPROACHES. A DEEP 
UPPER LEVEL TROUGH AXIS EXTENDS FROM 32N122W TO 24N126W TO 
05N124W WITH AN 8-10 DEGREE SWATH OF DRY AIR CENTERED W-E OF 
CENTRAL THE AXIS.

A LARGE UPPER LEVEL ANTICYCLONE IS CENTERED OVER MEXICO NEAR 
20N99W WITH A RIDGE AXIS EXTENDING TO THE NW OVER BAJA 
CALIFORNIA AND TO THE SW TO NEAR 10N116W. DIFFLUENT FLOW S OF 
THE RIDGE IS ENHANCING CONVECTION ALONG THE ITCZ E OF 111W 
ALTHOUGH CONVECTION HAS WEAKENED THERE DURING THE PAST 6 HOURS.
A NEARLY STATIONARY UPPER LEVEL CYCLONE IS CENTERED IN THE NW 
CARIBBEAN SEA NEAR 19N81W WITH AN UPPER TROUGH EXTENDING ACROSS 
HONDURAS AND NICARAGUA AND INTO THE E PACIFIC NEAR 07N91W. 
MOISTURE IS BEING ADVECTED FROM THE ITCZ TO THE NE ACROSS E 
COSTA RICA AND PANAMA AND INTO THE CARIBBEAN SEA.  

ELSEWHERE AT THE SURFACE...A COLD FRONT DISSIPATED JUST N OF 32N 
YESTERDAY ALTHOUGH REMNANT NORTHERLY WINDS OF 20 KT ARE 
OCCURRING N OF 27N E OF 124W AND ARE EXPECTED TO EXPAND TO N OF 
23N BETWEEN 116W AND 131W BY THU NIGHT. NORTHERLY SWELL UP TO 11
FT IS ALSO PROPAGATING S OF 32N ACROSS THIS SAME AREA AND IS 
ENCOUNTERING CROSS EQUATORIAL SOUTHERLY SWELL WHICH NOW 
STRETCHES ACROSS THE DISCUSSION AREA.

AN EXPANSIVE RIDGE DOMINATES THE MAJORITY OF THE DISCUSSION AREA 
N OF THE ITCZ EXTENDING FROM NEAR 32N135W TO 10N102W. 20 KT NE
TRADES WILL PERSIST S-SW OF THE RIDGE AXIS THROUGH THU NIGHT.

...GAP WINDS...
A 0320Z ASCAT SCATTEROMETER PASS CAPTURED NORTHERLY WINDS OF 
20-25 KT N OF 14N IN THE GULF OF TEHUANTEPEC. ONLY THE ECMWF HAD 
PREDICTED THESE STRONG WINDS MODEL GUIDANCE DIMINISHES THE WINDS 
TO LESS THAN 20 KT IN 12 HOURS.

$$
LEWITSKY