Mountain Weather Forecast

Time and Day: 9:00 Tuesday

The Snapshot: Dry and mild today, partly cloudy. Snow starting early Wednesday morning becoming moderate to heavy Wednesday afternoon and evening.

The Science: A transitory high pressure ridge will move across Washington State today during the daylight hours, with the next low pressure trough and associated front directly on its heels. After the front crosses the Cascade Crest early Wednesday morning, the mid and upper level flow will be favorable for supporting orographic snow showers at Stevens Pass. A Puget Sound Convergence Zone looks likely to set up, the question is whether it will be positioned over Stevens Pass, or further south.

The Long Range: Thursday provides a relative break in the active weather, looking mostly dry currently. Friday brings a weakening system with slightly rising freezing levels (~4,000”). The next one to watch is Saturday night/Sunday, which currently looks like a good snow producing event for the Washington Cascades.

Precipitation Ending at 4am: Today 24hr water =.10 Snow = 0-2” Tomorrow’s 24hr water = .75-1.0   Snow = 8-10” Trend and Timing: Light snow beginning early Wednesday morning, intensifying during the day, becoming moderate to heavy Wednesday afternoon/evening.

24hr temperature ending at 4 am tomorrow:                                        Low: 27    High: 32 Freezing level: 4000’, then 3,000’ Trend and Timing:    Daytime temps should peak this afternoon ahead of the front, rapid cooling early Wednesday morning.

24hr Winds (mph) ending at 4 am tomorrow: Base: W 5mph, then E 5-10 Ridge Top: SSW 5-10, then S 10-15 Trend and Timing:  Light west winds should give way to east flow through the passes Tuesday afternoon. DV