MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Thursday

The Snapshot:  Light snow showers with partial clearing can be expected today.  Snow increases overnight with moderate to heavy snow falling through the weekend.  

Snow totals by the end of the weekend could be in the 2-3’range.     

The Science

Current Observations:  It is lightly snowing this morning with 3” of snow that fell over the last 24hrs.   The temperature profile is 25 base / 21 ridges.  The barometer has bumped up to 1022mb’s with the 5000’ winds blowing 5-10 out the west.   The radar has a few light scattered snow showers falling in the mountains with the leading edge of the next system off of the southern BC coast.   

The Forecast:  A weak upper-level ridge will provide a relatively quiet day with some light snow showers and broken clouds throughout.

 A warm front, still well offshore, will push the next round of precipitation into the PNW tonight.  The Puget Sound Convergence Zone will set up shop tomorrow with strong westerly flow and good orographics developing.  Therefore expect gusty winds and moderate to heavy snow tomorrow.  Freezing levels will rise with these fronts but are expected to stay below 4000’.  

Weather Geek Speak:  Orographics = when moist air is lifted as it moves over a mountain range.  As the air rises and cools, orographic clouds form and serve as the source of the precipitation, most of which falls upwind of the mountain ridge.  This is what happens when the Puget Sound Convergence Zone develops.   

The Long Range:  The snow machine continues through the weekend.  Snow totals by noon Sunday could exceed 3’.     

    

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: .5  snow:4-6 Tomorrow’s 24hr water: 1  snow: 8-12 Trend and Timing: Light snow today with snow intensifying overnight.  The main bulk of moisture is expected after 4am tomorrow.

Temperature: Low:24     High: 28 Freezing level: 1500’-3000’ Trend and Timing:    Freezing level stay below 3000’ through the day with rising temperatures arriving early tomorrow morning.

Winds Base: 5-10 W Ridge Top: 5-15 W Trend and Timing: Winds will be westerly and intensify early tomorrow morning with the arrival of the front.