000
AXPZ20 KNHC 072145
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED APR 07 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...

AXIS WAS CENTERED ALONG 07N77W TO 05N85W TO 07N97W TO 03N110W TO 
04N130W TO 03N140W. SCATTERED MODERATE  FROM 04N TO 07N BETWEEN 
87W AND 92W...AND FROM EQUATOR TO 03N BETWEEN 103W AND 111W. 
SCATTERED MODERATE TO STRONG FROM 01N TO 05N W OF 129W. 

...DISCUSSION...

THE TAIL END OF A LONG WAVE TROUGH EXTENDS SW FROM THE SW U.S.TO 
BAJA CALIFORNIA NEAR 27N117W. A SMALL CYCLONIC CIRCULATION IS 
FURTHER W NEAR 27N130W. IN THE DEEP TROPICS...ACTIVE CONVECTION 
ALONG THE ITCZ IS MAINTAINING UPPER LEVEL RIDGING ALIGNED 
ROUGHLY ALONG 6N. 

AT THE SURFACE...WEAKENING SURFACE HIGH PRESSURE NORTH OF THE 
AREA IS STILL STRONG ENOUGH TO MAINTAIN A TIGHT PRESSURE 
GRADIENT BETWEEN THIS FEATURE AND THE ITCZ. FRESH TO STRONG 
WINDS CONTINUE FROM 05N TO 22N W OF 120W. AS AN UPPER LEVEL 
TROUGH AND ASSOCIATED COLD FRONT MOVE N OF THE AREA THROUGH 
TONIGHT WILL CAUSE THE THE ABOVE HIGH CENTER TO DISSIPATE...THEN 
BE REPLACED BY A STRONGER HIGH IN THE WAKE OF THE COLD FRONT ON 
THU. THE RESULTANT TIGHTENING PRES GRADIENT WILL PRODUCE A LARGE 
AREA OF TRADES OVER JUST ABOUT THE ENTIRE WESTERN HALF OF THE 
AREA N OF THE ITCZ. 

A TIGHT PRES GRADIENT BETWEEN THE AFOREMENTIONED HIGH PRES AND 
TROUGHING OVER THE SIERRA MADRE OCCIDENTAL CONTINUES TO RESULT 
IN NW TO N WINDS OF 20-25 KT N OF 22N E OF 123W. THIS GRADIENT 
IS ALSO RESPONSIBLE FOR NW WINDS OF 20 TO 25 KT THROUGH THE GULF 
OF CALIFORNIA N OF 25N. 

FRESH TO STRONG TRADES OVER THE CARIBBEAN WATERS CONTINUES TO 
FUNNEL THROUGH INTO THE GULF OF PAPAGAYO RESULTING IN WINDS TO 
20 KT. THE WINDS WILL PULSE OVER THE FORECAST PERIOD WITH THE 
STRONGEST WINDS IN THE EARLY MORNING HOURS IN RESPONSE TO 
ENHANCED NOCTURNAL DRAINAGE FLOW.
 
NORTHERLY WINDS OVER THE GULF OF TEHUANTEPEC WILL PRODUCE 20 KT 
WINDS AND 8 FT SEAS ON FRIDAY MORNING AND LAST FOR 12 HOURS. 

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

$$
FORMOSA