CASE 24 - Afternoon convection over SMO

8/11/04

Microphysical scans 2100 - 2300 Z, 2h

 

 

SYNOPTIC CONDITIONS SUMMARY:

 

 

The midlevel high pressure system over SW US weakened and displaced southward.

 

Convergence line in NW Mexico and upper-level divergence favored convective processes in Sonora and Chihuahua.

 

The convergence line which crossed the country from Tamaulipas to West of Mexico associated with the tropical wave # 31 produced the severe storm in Nayarit - S of Mazatlan

 

 

 

Day 0 forecast discussion text

 

Winds

200 mb - model.ETA.200408120000.00_200mb_wnd.gif

500 mb - model.ETA.200408120000.00_500mb_wnd.gif

700 mb - model.ETA.200408120000.00_700mb_wnd.gif

850 mb - model.ETA.200408120000.00_850mb_wnd.gif

 

 

 

EVENT SUMMARY:

 

24 h precipitation totals -

 

 

S-POL SUMMARY: Took 2h of microphysical scans of afternoon convection over the SMO. RHIs through various cells found overshooting tops and descending rear inflow jets. Ended microphysical scanning once convection moved in greater azimuthal coverage was needed.

 

S-Pol log - spol_081104.txt

 

SCAN OVERVIEW:

 

2015 Z

Convection developing over the SMO.

 

2024 Z, GOES-10 Vis

 

2100 Z

Beginning Microphysical Scanning, Switching to MicroFar135: Centered on 67 deg, RHIs at 97 & 99 deg.

 

2100 Z, Base reflectivity

 

2122 Z

Captured nice overshooting top in an RHI at 104 deg.

 

2130Z, Base reflectivity

 

2137 Z

Nice rear inflow jets observed from RHIs at 105 and 107 deg.

 

2223 Z

Nice overshooting top and upper level divergence in RHI at 92 deg.

 

2230Z, Base reflectivity

 

2300 Z

End Microphysical Scanning, Switching to ClimoFar: Cells have moved farther into S-Pol range and are occupying a swath 135 deg - switching back to 360 deg coverage.

 

2300Z, Base reflectivity