MOUNTAIN WEATHER FORECAST

Stevens Pass Mountain Weather Forecast

Day and Time: Thursday 0700

**  Rain bullet officially dodged- yes!

Current Observations:

24hr Precipitation: .29” swe, 5” of snow

Temperature profile: 33 base, 32 ridge

Pass level winds: Calm SW

Barometer: 1013mb’s and rising

Sky: OC

Radar: Scattered showers moving NE along the western slopes

The Forecast: Snow showers will diminish today with dry and partly cloudy conditions developing. This dry, mostly clear and relatively warm weather will continue through the weekend.  

Long Range: This benign weather period will likely last through the middle of next week.     

The Science:  A high pressure ridge, stretching from Northern Idaho down through the Southern Rockies, will begin to block any storms trying to make their way east.  Active weather over the coastal waters will keep the skies from becoming completely clear over the mountains.  

Strong east/offshore flow will form over the next few days.  This will keep freezing levels around 4000’ at Stevens Pass and along the eastern slopes.   Freezing levels over the western portion of the state are expected to be peak +-7500’ over the weekend.  

Confidence is good for the short term and low in the long-range (Tuesday+) due to large model discrepancies.     

Values from 4am today through

 4am tomorrow.

Precipitation: Today 24hr water: .<25  snow: 1-2 Tomorrow’s 24hr water:0   snow: 0 Trend and Timing: Snow showers will taper of this morning.

Temperature: Low: 28    High: 34 Freezing level: +-4500’ Trend and Timing:    Freezing levels will settle around 4500’ today and remain at that elevation for the next few days.

Winds Base: 0-5 W shifting E Ridge Top: 5-10 W shifting E Trend and Timing: This mornings short period of westerly winds will shift easterly tonight.

Glossary of PNW Weather Terms: 

Storm Water Equivalent (SWE)…. how much water is in the snow or rain

Orographic lift…. an airmass that is lifted as it moves up and over higher terrain. This promotes cloud development, and enhances precipitation.

Dirty Ridge…. a weak, unorganized high pressure ridge.

Advection…. the transfer of heat by the flow of fluid.  For the PNW, this is usually from warm moist air entering the region from the south.

Flow…. wind direction.  In meteorology, the wind direction is always noted where the wind is coming from.   East flow is wind coming from the east; SW is from the south west…