By Gordon McCraw, Meteorologist for the Tillamook County Pioneer
Thursday, December 22, 2022
First, to give a perspective on the forecast, I am writing this at about 2:30PM after attending a Special Weather Briefing from the National Weather Service.
Currently the Artic air continues to be pushed into the area by the strong easterly winds that are blowing 20-25 gusting to 30 across the area. This is making the current temperature of 32 feel like it is around 15-20 degrees with the windchill. Next on the agenda is moisture being pushed northeastward by an approaching warm front that is moving in from our southwest. As I type this, there are reports of precipitation in the Eugene area and Springfield is seeing snow. As I have been mentioning, for us, we likely first see snow starting in the next few hours, then as the warmer air pushes in above the surface levels, the snow will melt in the warmer area before refreezing before it hits the ground in the form of sleet, maybe as early as 4PM. Shortly after that, as the warm layer thickens the moisture does not have enough time to refreeze, so it hit the ground as rain, but as the surface temperatures are still below freezing, it ices over on the ground, this is called freezing rain, this likely happening by maybe 5-6 or 7PM tonight.
The freezing rain will continue tonight, and we see maybe 0.1-0.3” of ice buildup from the event, but as the warm air layer thickens, it will finally warm up the surface temperatures in the early morning hours tomorrow, Friday. This will be aided by the winds becoming more southeasterly, still 20-25 gusting to 35. The overnight low temperature will actually be increasing to just above freezing before sunup, when it typically is the coldest which is a good sign.
The temperatures will continue to climb tomorrow morning so the ice event will come to a close west of the Coast Range with the afternoon high around 49, but should you have travels plans across the Coast Range, it will take a while longer for them to see the improving conditions as their temperatures were much colder to start plus the north valley temperatures and winds will be such that their transition will also be slower which will impact the east side of the passes. And remember, they will be seeing snow, then ice with accumulations as high as ½”. They likely do not transition to rain until tomorrow afternoon, even later on the east side of the passes. To make life more fun across the passes, they do fall below freezing again Friday night so more freezing rain is possible on top of the refreezing ground moisture.
Back to Tillamook for Friday night, we will continue to be cloudy and rainy, but the southerly winds ease and the low only drops to near 43.
Christmas Eve we remain cloudy and rainy with breezy southerly winds 10-15 gusting to 35, the high near 54, the rain eases some later that night for Santa, lows near 44. Total rainfall about an inch.
Christmas Day, yep, more rain, maybe not a much as the day before, highs near 55, the rain and winds increases Christmas night, lows near 49.
As for next week, the models still suggest periods of heavy rain possible as a trough and its associated low pressure area moves into the region. This continues to signal the possibility of hydrological issues for our rivers, especially the Nehalem, maybe even the Wilson River. Something to watch for after the holiday weekend.