000
AXPZ20 KNHC 160316
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON AUG 16 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 
0245 UTC.

...TROPICAL WAVE...

A TROPICAL WAVE CURRENTLY N OF 07N ALONG 97W TO 98W. SCATTERED 
MODERATE WITH ISOLATED STRONG CONVECTION IS FLARING WITHIN 150 
NM W OF THE WAVE AXIS. 

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS ALONG COAST OF 
CENTRAL AMERICA BETWEEN 80W AND 93W. SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION CONTINUES ADVECT W OFF LAND OVER THE 
PAC WATERS WITHIN 150 NM OF THE PAC COAST FROM 80W TO 87W. 
SOUTHWESTERLY MONSOON FLOW DOMINATES THE PAC WATERS GENERALLY S 
OF 17N TO THE E OF 130W. MERGING LOW LEVEL NE FLOW AND CROSS 
EQUATORIAL SE FLOW SETS UP THE ITCZ AXIS ALONG 10N TO THE W OF 
130W...BUT IS CHARACTERIZED BY ONLY SMALL CLUSTERS OF MODERATE 
CONVECTION AT THE MOMENT.  

...DISCUSSION...

AN UPPER LEVEL RIDGE EXTENDS FROM THE SW UNITED STATES TO A 
CREST NEAR 23N138W. UPPER CYCLONES ARE OBSERVED ON BOTH SIDES OF 
THIS RIDGE...ONE STATIONARY JUST NW OF THE DISCUSSION AREA NEAR 
31N145W...AND A SECOND RAPIDLY FILLING AS IT MOVES W NEAR 
26N115W. SOME UPPER MOISTURE IS EVAPORATING WITHIN THE RIDGE... 
ROUGHLY WITHIN 180 NM OF 24N127W. ADDITIONAL UPPER MOISTURE IS 
BEING ADVECTED NE ALONG A NARROW PLUME ACROSS THE NORTHERN BAJA 
PENINSULA TO OVER SW ARIZONA AND WESTERN NEW MEXICO.

DENSER UPPER MOISTURE...ORIGINATING FROM DEBRIS CONVECTION 
PARTIALLY ASSOCIATED WITH THE UPPER CYCLONE NOW NEAR 26N115W AND 
INTENSE AFTERNOON CONVECTION THAT FLARED OVER INTERIOR OLD 
MEXICO...HAS SPREAD OUT TO THE N OVER EXTREME SE ARIZONA...
AND TO THE SOUTHWARD ALONG THE W COAST OF OLD MEXICO FROM 30N TO 
20N...AND IS ALSO ADVECTED SW OVER THE PACIFIC WATERS FROM 13N 
TO 20N BETWEEN 104W AND 117W. SCATTERED MODERATE CONVECTION IS 
DISSIPATING WITHIN 150 NM SW SEMICIRCLE OF A SURFACE LOW PRES 
NEAR 19N108W. ASSOCIATED DEBRIS MOISTURE FROM THIS CONVECTION 
CONTRIBUTES TO THE PLUME PREVIOUSLY DESCRIBED.  

AN W TO E SURFACE RIDGE EXTENDS FROM 32N140W TO NEAR 20N118W. 
THE PRESSURE GRADIENT BETWEEN THIS RIDGE AND TROUGHING IN THE 
GULF OF CALIFORNIA IS SUPPORTING NW FLOW TO 20 KT ALONG THE PAC 
COAST OF THE NORTHERN BAJA PENINSULA. THE GRADIENT IS EXPECTED 
TO RELAX SOME OVER THE PAC ON MON...BUT CONTINUE SOUTHERLY WINDS 
TO 20 KT TONIGHT AND MON OVER THE NORTHERN GULF OF 
CALIFORNIA.     

$$
NELSON