Storms Move Across Tucson At Dusk

Yesterday's early WRF-GFS correctly forecast the trend again - catching both the down day on Saturday and a widespread storm day yesterday (Sunday 19 August 2012). The timing was off a bit again, as has been the case much of the summer, with the storms moving into town about 2-hours later than forecast.
Photo above is looking toward the north-northeast as storms were approaching the Catalinas. Photo below is about an hour later (around 7 pm) as the leading edge of storms was nearly overhead.

Nearly same time as above, but looking toward the east-southeast.

The time-series above from TUS shows the nearly 30F temperature drop as the gust front moved by from the east - the airport had gusts to 40 mph with 0.32"; DM AFB had 45 mph with 0.42"; Atmo had gusts to a bit over 60 mph and 0.50"; here at house we had gusts to around 40 mph and 0.28". The Atmo gust was reported as a severe thunderstorm, although the anemometer is on top of a six story building. It gusts over 60 mph frequently and has never been used in severe storm reports before.

The TUS composite radar chart for 7 pm MST is shown above. Across the ALERT network 72 sites had rainfall (areal coverage a  bit over 75%). Amounts of more than half an inch occurred at 23 gauges; amounts over an inch fell at 4 gauges in the Catalinas; and Whitetail had 2.64". Not surprisingly, the Rillito was running this morning. A significant event that was very well forecast by the WRF-GFS model.