The figure above indicates the forecasted high in orange (with error bar denoting the range of ensemble forecast members), average high for this time of year in orange (dashed line), forecasted low in blue (with error bar), average low this time of year in blue (dashed line), and forecasted wind speed in purple. Note that the wind speed forecast is sustained wind (not gusts), and it is based on only one model (not an ensemble).
A large upper-level trough is digging south along the West Coast today, and will direct most, strong southerly flow into the mountains of northern Arizona Thursday evening – Friday. The forecasts are now indicating that the snow levels will remain at or above 5,500' for most of the duration of the event until late Friday morning, although snow levels will probably drop to around 5,000' late Friday morning to afternoon for perhaps 1-2 inches of wet snow accumulation in association with some of the heavier showers. Higher elevations around Prescott at or above 7,000' could see 6 – 12" of snow or more. A series of weak disturbances will follow this initial storm system for a lingering chance of rain or snow showers for most of the weekend. Some additional snow accumulation of perhaps 1-2 inches is possible on Saturday. Watch for slippery spots on the roads around Prescott, especially in the morning hours each day through Sunday.
Expect increasing southerly wind the next couple of days, gusting to near 35 mph on Thursday afternoon and evening. Expect increasing clouds, with a chance of rain beginning during the late afternoon on Thursday and becoming heavier in the evening hours. Snow levels will begin around 7,000' on Thursday, but by late Thursday evening to Friday morning, a cold front will move across the state, lowering snow levels to around 5,500' by Friday morning. Expect storm total precipitation between 0.5" and 1.5", with perhaps 1-4" of total snow accumulation for the weekend (although any snow accumulation will probably melt quickly).
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Official National Weather Service forecast