Monday, November 28, 2016
Fast-Hitting Nighttime Winds and Light Rain
Bit of snow at higher elevations early this morning. Above shows a couple of inches at General Store in Summerhaven and below shows just a dusting at Kitt Peak.
Here at house we had 30 to 40 mph winds as the front passed and some rain both before and after midnight. Total ended up at 0.11" and the GEFS average from 06 UTC yesterday morning was quite good - 06 UTC WRF versions were a bit dry for the metro.
Several issues noted this morning. First, the Pima County ALERT map (above for 24-hour precipitation though 7:00 am MST) no longer fits my screen well, and I can't do a proper snip to show the entire array. Rain amounts were generally quite light, but one site on Redington Pass reports over half an inch.
Sadly, the old version display of the data (metro west sector below) is no longer updating. This is distressing to me, since the old version is (was) extremely versatile wrt examining precipitation across varying time periods and also for looking back to past events. Serious loss for those interested in using the ALERT data for research.
Finally, the radar/gauge product from WDT (below, which is my preferred product of this type) illustrates some beam blockage artifacts this morning - below is 24-hour estimate and sectors where lowest beams are blocked show clearly. Reason for this is that the precipitation echoes with this event had very low tops - thus, if gauges not available then radar estimates were too low where lowest tilts weren't available. Radar-based precipitation estimates remain a difficult product to evaluate or use in research where terrain is complex and substantial beam blockage is present.
Posted by Bob Maddox at 7:13 AM