UA WRF Forecast Discussions

Synopsis A low pressure system in Southern California will gradually move eastward into Arizona leading to unsettled weather through Wednesday night. Precipitation will mainly impact the higher terrain in Northern Arizona today and tomorrow with precipitation chances increasing in Southern Arizona on Wednesday. Rainfall amounts will be light and variable with a trace to 0.25 inches in the lower deserts and between 0.25 and 0.75 inches over the higher terrain with locally higher amounts possible along favorable southwestern facing slopes of the Mogollon Rim. Snow levels will remain mainly above 4000 feet today and tomorrow with total 72-hour snow accumulations ranging  from a dusting to 4 inches, but locally higher amounts are possible over the tallest peaks of Northern Arizona. On Wednesday, snow levels will likely drop to 3000-3500 feet which means some higher valley locales could receive a dusting of snow.  Current Conditions As of 11AM MST, visible satellite imagery an...

Synopsis An upper level closed low, currently centered over the lower Colorado River Valley, will continue to dig southward into Northern Mexico throughout the day today. This feature is expected to provide Arizona with cold temperatures, strong winds, and scattered, light precipitation late tonight through Wednesday. Easterly winds on the order of 20 to 40 knots are expected across the region with strongest wind speeds over the higher terrain and in Southeastern Arizona late tonight through Wednesday afternoon.  Even though this upper level low is dynamically robust, it is quite moisture starved leading to only light precipitation accumulations.  Snow levels will be relatively low with some light snowfall possible in some of the valley locations mainly east of Tucson and above 3000 feet. Snow accumulations over the high terrain will be light with only 1 to 3 inches possible. Besides precipitation chances, Wednesday will be a chilly day across Ari...