The NWS Warning Map is once again lit up. (Dark Green) Flood Watch Thursday and Friday for another inch of rain in the valley this afternoon and tonight and more rain Thursday night into Friday morning. In addition a warm front Wednesday night will bring rising snow levels to 6,000’ Thursday morning, leading to run off. At least several rivers will be near Flood Stage Thursday night and Friday morning.
A new Winter Storm for the Cascades today for another foot plus of new snow, A Winter Storm Warning for the Gorge Noon Today - 10am Thursday for additional 3-9” of snow in Hood River. Gorge temps at lowest elevations will warm above freezing today and see a daytime wet mix, followed by freezing overnight temps with snow. Dry weather finally takes hold late Friday and continues through the weekend.
NWS has issued a Winter Storm Watch for the Willamette Valley and southwest Washington for Saturday afternoon through Sunday night. The main snow threat at low elevations, including downtown Portland continues to be Saturday evening into Monday morning. I still believe most areas will wake up to snow on the ground Sunday morning.
My forecast continues to call for 2-5" of accumulation through Sunday daytime with another 1-3" of possible snow Sunday night into Monday morning. The fact that Sunday afternoon temps may warm to 35 degrees makes the low elevation snow forecast somewhat uncertain. However, near and above 500 feet should see see at least 6" through the period and possibly 8-10" with sticking snow beginning Christmas Day.
Snow update time. Keep in mind the graphic shows current output from weather models that generally agree through the day Wednesday. Tomorrow, timelines, snow amounts, temps etc will likely change somewhat. I am giving you daily details, in an effort to paint a possible picture of what to expect as the cold air arrives. Understand that updates and changes are LIKELY!