000
AXPZ20 KNHC 122135
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED MAY 12 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 
2100 UTC.

...ITCZ...

ITCZ AXIS ALONG 04N83W TO 05N90W TO 05N100W TO 08N115W TO 
07N140W. SCATTERED MODERATE CONVECTION WITHIN 150 NM N OF THE 
AXIS BETWEEN 83W AND 87W...WITHIN 120 NM N OF THE AXIS BETWEEN 
91W AND 95W...WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 116W 
AND 124W...AND WITHIN 180 NM EITHER SIDE OF THE AXIS BETWEEN 
124W AND 137W.

...DISCUSSION...

AN UPPER LEVEL TROUGH EXTENDS SW FROM NEW MEXICO NEAR 32N106W TO 
27N116W TO 22N140W. MAINLY DRY AIR IS IN PLACE N OF THE TROUGH 
AXIS.

A BROAD UPPER LEVEL TROPICAL ANTICYCLONE IS POSITIONED NEAR 
07N128W WITH A RIDGE AXIS EXTENDING ALONG 07N BETWEEN 97W AND 
140W. CONVECTION IS BEING ENHANCED ALONG AND S OF THE RIDGE 
UNDER UPPER DIFFLUENCE ALONG THE ITCZ MAINLY W OF 115W. A 75-95 
KT JETSTREAM IS BETWEEN THE ANTICYCLONE CENTER AND THE ABOVE 
MENTIONED UPPER LEVEL TROUGH PRODUCING PLENTIFUL MIDDLE TO UPPER 
LEVEL MOISTURE WHICH IS BEING ADVECTED FROM THE ITCZ TO THE NE 
ACROSS CENTRAL MEXICO.

ANOTHER UPPER LEVEL ANTICYCLONE IS DEVELOPING NEAR 10N92W WITH A 
RIDGE AXIS EXTENDING TO THE N INTO THE GULF OF MEXICO WITH VERY 
DRY AIR IN PLACE N OF 08N BETWEEN 87W AND 98W. ANOTHER UPPER 
RIDGE EXTENDS FROM NORTHERN COLOMBIA INTO THE FAR E PACIFIC NEAR 
07N87W. UPPER LEVEL DIFFLUENCE UNDER THIS RIDGE IS ENHANCING 
ITCZ CONVECTION E OF 87W.
 
AT THE SURFACE...A BROAD RIDGE AXIS DOMINATES THE MAJORITY OF 
THE DISCUSSION AREA WITH ITS AXIS FROM NEAR 32N134W TO 12N106W. 
NE TRADES IN THE 20-25 KT ARE SW OF THE RIDGE AXIS FROM 09N TO 
25N W OF 120W. 20 KT NW-N WINDS ARE OCCURRING NE OF THE RIDGE 
AXIS N OF 22N BETWEEN 113W AND 123W. NE AND NW SWELLS ARE THE 
PRIMARY SWELLS OVER THE WATERS WHERE THE TRADES AND NW-N WINDS 
ARE OCCURRING WITH A SERIES OF LONG PERIOD CROSS EQUATORIAL 
SOUTHERLY SWELL GROUPS DOMINATING THE REMAINDER OF THE 
DISCUSSION AREA. THE HIGHEST COMBINED SEAS OF UP TO 12 FT ARE 
OCCURRING ALONG 10N W OF 130W.

1008 MB LOW PRES IS CENTERED NEAR 04.5N80W WITH A TROUGH 
EXTENDING FROM 07N77W TO 01N82W. NUMEROUS MODERATE AND ISOLATED 
STRONG CONVECTION IS OCCURRING WITHIN 180 NM NW OF THE LOW AND 
TROUGH. THE LOW IS EXPECTED TO DISSIPATE DURING THE NEXT 24 
HOURS WHILE THE TROUGH SLOWLY DRIFTS TO THE W-NW THROUGH THE 
NEXT 48 HOURS.

GAP WINDS...NE TO E WINDS AT 20 TO 25 KT ARE SURGING OVER THE 
GULF OF PAPAGAYO AND DOWNWIND TO NEAR 10N90W AND ARE EXPECTED TO 
PERSIST THROUGH AT LEAST THE NEXT 48 HOURS.

$$
LEWITSKY