Update, Tuesday 11:15 AM: The atmosphere remains moist today and will become unstable this afternoon and evening for the possibility of thunderstorms with snow or snow pellets (also known as “thundersnow”). Anywhere between 0 – 2” of snow accumulation is possible this afternoon through this evening, as indicated by the various forecast models. The air will finally clear once and for all late this evening.
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).
The third in a series of three winter storms is moving across the Southwest today – tomorrow morning. Associated with the large upper-air trough is a much colder airmass and surface cold front that is soon to pass through the area, changing the mixed precipitation to all snow showers. Expect 1-2” of snow accumulation this afternoon through possibly tomorrow morning. Roads could be slick tomorrow morning, as temperatures will be dropping well below freezing and snow levels will lower to 3,000’ late tonight.
Skies will become mostly clear Tuesday afternoon through the rest of the week, and no more precipitation is expected Wednesday through the coming weekend. Winds will become light except for some breezes on Friday and Saturday. Temperatures will be well below normal for the rest of the week, so bundle up and protect your pipes from freezing!