Mountain Weather

THIS IS NOT A REAL FORECAST. THIS IS USED FOR TESTING PURPOSES ONLY! NWAC NOR RACHEL IS NOT RESPONSIBLE FOR YOU NOT READING THIS FIRST LINE AND THINKING THIS IS REAL.

After a brief warm-up late Thursday, we'll be in a prime snow accumulation pattern. A moisture-laden frontal system continues to impact the region with the full array of winter weather, including heavy snow, heavy rain, and possibly freezing rain. The core of the moisture and warm sector is directed from the mouth of Columbia to Mt Rainier and southward as of Thursday afternoon, but plenty of moisture (and a brief warm-up) is spilling north of that boundary as well. With low-level E flow until about 6 PM, we're expecting a brief period of freezing rain before a changeover to rain at Snoqualmie Pass and most locations near and west of the Cascade Crest, up to around 5000 ft in the north and 6000-7000 ft in the south. As the front drags southeast, expect cooler air to return. A secondary front moving through around 8 PM should bring an uptick in rain/snow shower activity in the late evening hours and is likely to trigger convergence, initially over the Mountain Loop, then the Stevens Pass area overnight.

By Friday morning, most areas will see snow levels steady around 1000-2000 ft with light snow showers becoming moderate in the afternoon. Moderate snow showers continue on WSW flow through Saturday with a very subtle increase in snow level, but snow levels should remain below all major passes.

THIS IS NOT A REAL FORECAST. THIS IS USED FOR TESTING PURPOSES ONLY! NWAC NOR RACHEL IS NOT RESPONSIBLE FOR YOU NOT READING THIS FIRST LINE AND THINKING THIS IS REAL.

A complex winter storm system is tracking toward southern Vancouver Island on Thursday. A band of moderate snow lifts NE across the region Thursday morning, ahead of an occluded front. The heavier precipitation targets the central and southern Cascades during the late morning through evening hours as the system's warm sector passes through. This will create some complex weather for the passes as low-level E flow intensifies, keeping the pass levels cold, while warmer air moves in above 4500 ft. This makes the risk for freezing rain during peak precipitation from around 3 PM to 7 PM before the front pushes through and the flow switches westerly. This westerly flow brings decreasing light to moderate rain and snow, transitioning to all snow as snow levels drop to and then remain around 1500 ft by Friday morning. With an upper trough offshore and sustained light to moderate WSW flow, expect snow showers to bring substantial accumulations to the W slopes of the Cascades Thursday night and Friday.

We're expecting 6-10" snow totals for areas above the rain/snow line on Friday, but rain or freezing rain will eat into snow totals below 4500-6500 ft for the central and southern Cascades. The southern Cascades should pick up the most snowfall Thursday night, with up to 5-15" of snow, and 3-8 further north. Friday will bring another 4-10" of snow for many locations across the Cascades.