Tuesday, January 11, 2011

Snow, Ice, Rain, somewhere!

Cool and dry this morning, temperatures in the mid 30s but with the strong east wind it feels like it’s the upper 20s. The models are still somewhat conflicting on this event, but, we have a high pressure area over the Rockies, pumping cold area in from the east, and a low pressure center, with an associated warm front, moving into the area from the southwest. The two combine over northwest Oregon and southwest Washington (somewhere) to give us an interesting mix of precipitation tonight. Right now we expect the rain to move in from the southwest after 10am this morning, bringing some low level snow across the Coast Range and into the valley north of Salem later today. It will remain breezy also with southeast winds 10-15 gusting to 25. As the warm front gets closer, starting around 10pm tonight, it will warm up the upper atmosphere first (called overrunning), so, the precipitation that had been falling as snow will now fall as rain, but, with the surface temperatures in some area still below freezing, the rain refreezes on contact, giving us freezing rain. The temperature will continue to slowly rise until by 4am Wednesday the freezing level rises above the pass levels at the Coast Range. The winds will still be breezy, now southerly 20-25 gusting to 30, higher at the beaches and headlands. Wednesday more rain, warmer with highs now in the low 50s and lows in the upper 40s, still breezy with south winds 10-15 gusting to 25. Thursday another system bring more rain into Friday, it stays warm, into the mid 50s during the day, and the active wet pattern continues into MLK Monday.

Advisories, Watched, Warnings

High Wind Watch from this afternoon thru Wednesday morning for southerly winds along the beaches and headland 30-40 gusting to 60. This should be upgraded to a High Wind Warning soon!

Winter Weather Advisory for the Coast Range from 1pm this afternoon thru midnight tonight for 1-3” of snow and 1/10 to ¼” of ice through the passes. The snow level as low as 300’ before rising well above the pass level by 4am.

Ice and snow accumulation will cause significant driving hazards, including on Hwy 6, 26, and 30, these hazards extend into the valley and I-5. Drive carefully, take your time, and check the weather and road conditions prior to leaving.


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