Another 2-3 Feet of Snow Expected This Weekend at Diamond and Crater Lake

Crater Lake now has 69 inches of snow and Diamond Lake has a base of around 33 inches according to Diamond Lake Resort. But lots more snow is on the way for both locations with an expected 2-3 more feet set to fall this weekend! Here is the latest forecast discussion through Sunday night from the NWS in Medford. "A cold front has pushed south of the forecast area with cool unstable air spreading into southern Oregon and northern California. We did see the KOTH sensor detect some lightning earlier this afternoon, so there is definitely some instability out there with plenty of vertical motion and moisture in the snow growth zone. Showers are little more widespread than previously anticipated, although it seems snow is really struggling to accumulate at lower elevations due to warmer temperatures at the surface. Snow has generally been making it down to 1500 feet all day, although it's only accumulating at higher elevations, generally 2000 feet and higher. That will change later tonight as cooler air moves in with snow levels falling to 1000 feet. Temperatures do drop tonight behind the front, although snow accumulation should be minimal as the upper waves progress through the region. Vertical motion should decrease, so it makes sense showers will be on the downtrend. The one place where it seems the showers persist are locations in the higher Cascades near Crater Lake and Diamond Lake. With the flow becoming more westerly, topographic lift seems to be the main driver here. There are little to no showers and precipitation accumulation in other locations across the region early Thursday. That gradually begins to change heading through the day. Probability of precipitation begins to increase up to 80 to 90 percent in the Cascades Thursday evening with the coverage of snow increasing. Snow levels start out around 2500 feet ahead of the leading edge of this next atmosphere river (AR). The leading edge of the next AR will hit the region late Thursday night into Friday morning. Integrated water vapor transport (IVT) values/vectors look pretty good for a Cascade snow event. The GEFS suggests there is about a 24 to 36 hour period of moist westerly flow in our forecast area with a good chance of IVT values > 500. Snow levels increase up to 3500 feet Friday evening before increasing further up to 5500 feet ahead of a warm front or perhaps another pocket of warmer air. The other topic worth mentioning is winds really building late Friday east of the Cascades and over higher terrain. These winds could really cause some problems east of the Cascades when mixed with the stronger winds. The takehome message here is the Cascades will really be under pressure for a 48 hour period between 10 pm Thursday and 10 pm Saturday. We officially have about 3 feet of snowfall around Crater Lake ending Sunday evening with relatively lower totals in the Siskiyous and mountains in northern California. The winds mixed with the snow could create additional hazards and travel conditions. The other interesting thing about the guidance is the ensembles are hinting at some higher snowfall than what we usually see east of the Cascades with a few ensemble members suggesting some very high snowfall there. Right now, we're officially forecasting up to a foot or snow around Lakeview and generally 6 to 12 inches over many other locations in Lake and Klamath Counties. Chemult appears to be the winner with up to 17 inches there. Keep in mind there are ensemble members which are forecasting much higher than this. This seems could be from a cooler low moving in later Saturday with some lower snow levels to impact valley floors. In any case, areas east of the Cascades should get a fair chunk of snow with this event compared to our usual Cascade snow events. -Smith" For the latest forecast discussion: https://www.weather.gov/wrh/TextProduct?product=afdmfr