CASE 20 - Nocturnal landbreeze front convection

8/8/04

Microphysical scans 0930 - 1145 Z, 2h 15m

 

 

 

IOP status - end of IOP #7 (see report). The IOP was originally scheduled to end 12 Z on 8/7/04, but models suggested a very wet pattern during the third 24h period that would last into 8/8 prompting the extension.

 

An upper-level 250 mb high moved across the AZ/MX border, bringing easterly flow into the southern zones of Tier 1. The evening of 8/7, the easterly flow around the UL high pushed precipitation in the southern Tier 1 zones towards the W Mexico coast.

 

IV#9 S of Baja.

 

TW#30 and IV#10 present in the tropics.
 
SYNOPTIC CONDITIONS SUMMARY:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Day 0 forecast discussion text

 

Winds

200 mb - model.ETA.200408081200.00_200mb_wnd.gif

500 mb - model.ETA.200408081200.00_500mb_wnd.gif

700 mb - model.ETA.200408081200.00_700mb_wnd.gif

850 mb - model.ETA.200408081200.00_850mb_wnd.gif

 

Mazatlan SkewT - ops.SkewT.200408080900.Mazatlan_MX.gif - ops.SkewT.200408081200.Mazatlan_MX.gif

 

 

S-POL SUMMARY:

 

S-Pol log - spol_080804.txt

 

SCAN OVERVIEW:

 

0800 Z

Fine landbreeze front moving offshore to the W of S-Pol.

 

0800Z, Base reflectivity

 

0930 Z

Begin Microphysical Scanning, Switching to MicroFar135: A few cells are initiating along the landbreeze front as it moves offshore. Cells are located ~90 km S of S-Pol. Centered sector at 227 deg.

 

0930Z, Base reflectivity

 

0945 Z

Switching to MicroFar90: Centered on 205 deg. Convection is isolated enough to fit in smaller sector.

 

0945Z, Base reflectivity

 

1145 Z

End Microphysical Scanning, Switching to ClimoFar: Cells along landbreeze front dissipating, cells forming over SMO.

 

1145Z, Base reflectivity