000
AXPZ20 KNHC 100400
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JUL 10 2009

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 
0345 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS N OF 04N TO THE COAST OF MEXICO AND N TO 18N 
ALONG 98W TO 99W.  THIS TROPICAL WAVE IS MOVING W 15 KT. THE 
SOUTHERN END OF THE WAVE CROSSES THE ITCZ NEAR 09N. THE ONLY 
SIGNIFICANT CONVECTION ASSOCIATED WITH THE WAVE AWAY FROM THE 
ITCZ LIES WITHIN 45 NM OF THE MEXICAN COAST BETWEEN 94W AND 100W.

A 1007 MB LOW PRESSURE SYSTEM CAN BE FOUND AT 10N ON THE 
TROPICAL WAVE AXIS ALONG 110W/111W. THE TROPICAL WAVE EXTENDS 
FROM 04N TO 14N. THIS TROPICAL WAVE CROSSES THE ITCZ NEAR THE 
LOCATION OF THE EMBEDDED LOW. SCATTERED MODERATE CONVECTION CAN 
BE FOUND WITHIN 210 NM OF THE LOW. THIS SYSTEM HAS BECOME BETTER 
ORGANIZED OVER THE LAST 24 HOURS AND FURTHER DEVELOPMENT IS 
POSSIBLE DURING OVER THE NEXT FEW DAYS.  

...ITCZ...
THE ITCZ AXIS IS ALONG 06N77W TO 10N97W TO 08N104W TO 10N108W TO 
08N130W. NO DEEP CONVECTION IS NOTED W OF 130W. SCATTERED 
MODERATE CONVECTION CAN BE FOUND WITHIN 150 NM EITHER SIDE OF 
THE ITCZ AXIS BETWEEN 89W AND 107W.

...DISCUSSION...
A QUIKSCAT PASS FROM 1256 UTC TODAY SHOWED A LOW PRES 
CIRCULATION HAD DEVELOPED NEAR 10N ON THE TROPICAL WAVE ALONG 
110W/111W. UNFORTUNATELY...THE SUBSEQUENT ASCAT PASSES MISSED 
THE SYSTEM. CONVECTION ASSOCIATED WITH THE LOW AND TROPICAL WAVE 
HAS DIMINISHED SOMEWHAT SINCE EARLIER TODAY...BUT THE SYSTEM 
LIES IN A REGION OF UPPER LEVEL DIFFLUENCE BETWEEN THE RIDGE 
AXIS EXTENDING FROM THE UPPER LEVEL ANTICYCLONE CENTERED OVER W 
TEXAS SOUTHWESTWARD TO A WEAK ANTICYCLONE NEAR 15N107W TO NEAR 
07N123W AND UPPER LEVEL 20 TO 30 KT NORTHERLY FLOW S OF 08W IN 
THE VICINITY OF THE TROPICAL WAVE. CURRENTLY...SCATTERED 
MODERATE CONVECTION CAN BE FOUND WITHIN 210 NM OF THE EMBEDDED 
LOW. FARTHER N...THE EASTERLY FLOW AROUND THE SW SIDE OF THE 
ANTICYCLONE OVER TEXAS IS PUSHING THE AFTERNOON CONVECTION FROM 
THE SIERRA MADRE OCCIDENTAL MOUNTAINS TO WITHIN 45 NM OFF THE 
COAST N OF MANZANILLO FROM 18N TO 22N.

REGENERATION OF DEEP CONVECTION IS BECOMING SIGNIFICANTLY LESS 
LIKELY AS THE REMNANT LOW OF BLANCA MOVES OVER 22-23 DEGREE 
CELSIUS SEA SURFACE TEMPERATURES. THE REMNANT LOW HAS SCATTERED 
LOW-TOPPED CONVECTION DISPLACED TO THE NNW OF ITS LOW LEVEL 
CENTER AS THE SYSTEM LIES IN A REGION OF INCREASING SOUTHERLY 
FLOW ALOFT ON THE LEADING EDGE OF THE UPPER LEVEL TROUGH OVER NW 
WATERS.  HOWEVER...THE LOW LEVEL CIRCULATION REMAINS IN TACT 
WITH THE 1740 ASCAT PASS SHOWING WINDS IN THE 25 TO 30 KT RANGE 
WITHIN 150 NM IN THE N QUADRANT. 20 TO 25 KT WINDS ARE ALSO 
NOTED OVER FORECAST WATERS N OF THE SYSTEM BETWEEN 122W AND 129W 
WHERE THE PRESSURE GRADIENT IS STRONG BETWEEN THE REMNANT LOW OF 
BLANCA AND THE SURFACE RIDGE FROM 30N125W TO 23N114W. SURFACE 
RIDGING WILL STRENGTHEN BETWEEN THE REMNANTS OF BLANCA AND LOW 
PRESSURE OVER THE GULF OF CALIFORNIA. WINDS WITHIN 60 NM OF THE 
COAST OF BAJA CALIFORNIA WILL INCREASE TO 20 KT AS A RESULT.

STRONG NE TRADE WINDS ARE EXPECTED TO BLEED THROUGH CENTRAL 
AMERICA FROM THE WESTERN CARIBBEAN ACROSS THE GULF OF PAPAGAYO 
BEGINNING IN THE EARLY MORNING HOURS FRI AND PERSISTING THE NEXT 
FEW DAYS. WINDS TO 20 KT WILL IMPACT THE REGION W OF 88W...WITH 
POTENTIALLY STRONGER WINDS SEEN IN THE EARLY MORNING HOURS WHEN 
DRAINAGE FLOW IS AT A MAXIMUM.

$$
SCHAUER CLARK