Saturday, August 13, 2016
Suppressed Again Yesterday - Chance Of Storms Today
Middle clouds around this morning led to beautiful sunrise. Thunderstorm activity was quite suppressed again in our local area yesterday. Plot of detected CG flashes below (from Atmo and Vaisala) is for 24-hours ending at 6:00 am MST this morning. Two ALERT sites in Catalinas had rain of less than 1/10 inch during past day.
The morning sounding from TWC (skewT plot above from SPC) remains very unstable, even though PW has continued to slowly decrease. Middle-level temperatures have cooled substantially. Afternoon storm bases would be quite high, producing gusty outflows that could locally be severe. Steering level winds are muddled, with no organized flow regime established yet in lower troposphere. Winds around 500 mb will be trending toward north to north-northeasterly during the afternoon. Both the WRF NAM and GFS versions forecast late afternoon storms for eastern Pima County that propagate rapidly southward. The composite radar forecast below (from 06 UTC WRF-NAM) is valid at 6:00 pm this evening. The GFS version forecasts considerably more activity, but was also too active at sunrise. Regardless, could be an interesting evening.
Posted by Bob Maddox at 7:36 AM