MOUNTAIN WEATHER FORECAST

Time and Day:  1000 Sunday

The Snapshot: Continued inversion with very cold fog on the lower half of the mountain, warm and clear above. These conditions continue Monday.   

Current Observations:  There is currently a 30-degree difference between the top of Skyline and the base area, with Skyline reading 47 degrees and the base area a chilly 16! The dense fog layer continues to hang from about mid-mountain down, the RH at Schmidt Haus is 93%. Above the inversion layer it is balmy and clear.

The Science: The massive high pressure ridge remains in place today and Monday, bringing a continuation of the same conditions we’ve seen much of the past week. The strong inversion will continue to affect Stevens Pass with cold air being pulled thru the Cascade gaps and very warm air aloft. The free air freezing level this morning is around 10,000’. The ridge flattens a bit Monday night and Tuesday as a weak system rides over it to our north, the main result will be increased clouds over the Olympics and North Cascades, and maybe a few sprinkles in those areas.   

The Long Range: After the ridge rebuilds slightly Tuesday all models have it finally breaking down and moving east starting mid-week. This will allow for typical seasonal low pressure systems to re-enter the region, with the first currently looking to be a trough/cold front feature arriving Friday or Saturday. Way too far out to place any bets on but at least things are changing.   

From the NWS Seattle discussion: Beyond Thursday night it is back to our regularly scheduled December

weather with zonal flow aloft and a series of weather systems

taking aim at the area into next weekend.

Thank goodness. 

24hr Precipitation ending at 4am: Today 24hr water: 0 Snow: 0 Tomorrow’s 24hr water: 0 Snow: 0 Trend and Timing: No precip expected for the next 48 hours.

24hr temperature ending at 4am:  Low: 13 (in base area) High: 49 (on upper mountain) Free air freezing level: 10-11,000’ Trend and Timing:    Same conditions continue tomorrow.

24hr Winds (mph) ending at 4am: Base: East 10-15 Ridge Top: Variable 0-10 except E 10-15 around Tye Mill Trend and Timing: East flow thru the passes and variable light winds aloft thru tomorrow. DV