000
AXPZ20 KNHC 192147
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU JUL 19 2007

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.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 93W N OF 3N MOVING W 10 KT. LITTLE 
SIGNIFICANT CONVECTION IS ASSOCIATED WITH THIS WAVE. LOW PRES 
1009 MB CENTERED ALONG THE WAVE WHERE IT INTERSECTS THE ITCZ AT 
8N93W. THE WAVE AND LOW CENTER WILL CONTINUE TO BE SITUATED 
BETWEEN AN UPPER LOW OVER THE WRN CARIBBEAN AND AN UPPER 
ANTICYCLONE OVER CENTRAL MEXICO... RESULTING IN UNFAVORABLE 
CONDITIONS FOR SIGNIFICANT DEVELOPMENT AS IT SLOWLY MOVES W. 
  
TROPICAL WAVE ALONG 114W FROM 7N TO 18N MOVING W 15 KT. QUIKSCAT 
DATA SHOW STRONG LOW LEVEL CONVERGENCE OF SW AND NW FLOW ALONG 
THE ITCZ...INTERSECTING THE WAVE NEAR 12N114W. NO SIGNIFICANT 
CONVECTION IS NOTED AT THIS TIME. HOWEVER...GIVEN THE CONVERGENT 
FLOW IN THE LOW LEVELS...AND THE POTENTIAL FOR UPPER LEVEL 
DIVERGENCE ON THE E SIDE OF AN UPPER LOW CENTERED NEAR 
16N120W...FURTHER CONVECTIVE DEVELOPMENT IS POSSIBLE OVERNIGHT. 
THE WAVE WILL MOVE INTO AN AREA OF DRIER AIR TOMORROW...LESS 
FAVORABLE FOR SIGNIFICANT DEVELOPMENT.

TROPICAL WAVE ALONG 131W FROM 7N TO 16N MOVING W 15 KT. NO 
SIGNIFICANT CONVECTION ASSOCIATED WITH THIS WAVE AS IT IS IN AN 
AREA OF SUBSIDENCE UNFAVORABLE FOR CONVECTIVE DEVELOPMENT.

...ITCZ...
AXIS 8N83W 7N97W 17N102W 8N124W 12N133W 10N140W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 90 NM OF LINE 18N108W 15N111W. 

...DISCUSSION...
E OF 100W...WEAK SURFACE LOW 1009 MB CENTERED NEAR 8N93W IS 
EXPECTED TO CONTINUE WNW ALONG A TROPICAL WAVE. CONVECTION 
ASSOCIATED WITH THE LOW/WAVE IS ACTIVE FROM 11N TO 13N BETWEEN 
93W AND 95W. MODEL CONSENSUS IS THAT THIS LOW WILL MAINTAIN 
ITSELF AS IT MOVES W ALONG 9N THROUGH THE WEEKEND...BUT WILL NOT 
DEEPEN SIGNIFICANTLY. ANOTHER TROPICAL WAVE WILL PANAMANIAN 
WATERS THIS WEEKEND.

W OF 100W...QUIKSCAT DATA SHOW THAT SWLY FLOW CONTINUES INTO THE 
ITCZ E OF 115W. AN UPPER TROUGH EXTENDS FROM NW MEXICO TO 
19N115W TO AN UPPER LOW NEAR 15N122W. UPPER DIVERGENCE SE OF 
THIS TROUGH IS COUPLED WITH THE LOW LEVEL SWLY CONVERGENCE TO 
ENHANCE CONVECTION ALONG THE ITCZ...AS DEPICTED ON SATELLITE 
IMAGERY BY A LARGE CONVERGENT LINE FROM 7N125W TO A WEAK 
CIRCULATION NEAR 22N107W ALONG THE MEXICAN COAST. GENERALLY DRY 
MID AND UPPER LEVELS PREVAIL ALONG AND NW OF THE UPPER TROUGH. 
AT THE SURFACE...FRESH NWLY WINDS REMAIN OFF THE BAJA 
COAST...ALTHOUGH THIS HAS BEEN RAPIDLY WEAKENING SINCE A WEAK 
SURFACE TROUGH PUSHED INTO THE AREA. THE SWLY CONVERGENCE WILL 
DIMINISH BY THE WEEKEND AHEAD OF THE LOW MOVING W ALONG 9N. 
WINDS WILL INCREASE MODESTLY TO 20 KT AROUND THE LOW BY 48 HOURS.

$$
CHRISTENSEN