We’ve had an early “pre-show” of snow today, but the main event is still on! Everything in the previous posting is still valid. We have a snow/ice “event” beginning in Portland this morning and for the first time in almost 2 years we actually have a cold & snowy day for the kids (and adults).
HIGHLIGHTS FOR WESTERN VALLEYS
(Includes all lowland areas from Longview to Albany)
- NO THAWING…Temperatures remain in 20s or around 30.
- Light snow at times through 10am
- Increasing snow midday/afternoon
- Possibly freezing rain/ice pellets mixed in by late afternoon/evening. An icy glaze MAY develop on top of snowy roads. If we’re lucky it’ll remain as mainly snow.
- 1-4″ total, by late this evening, depends on whether we switch to ice pellets/freezing rain at some point.
- Blowing and drifting snow east metro in the gusty gorge wind areas. Yes it’s possible to get 1 foot drifts out of 2-3″ of snow.
- Roads snow-covered & icy through Monday morning commute
Sorry about the early arrival, a band of light/moderate snow worked it’s way north ahead of the main moisture this morning. I got almost an inch out of that one here at home. Radar shows that decreasing now but the radar is already beginning to “backfill” with additional precipitation.
The short-term HRRR model shows precipitation picking up and coming down steadily from 11am onward into the evening. Once again it has increased total precipitation up into the .30 to .40″ range. IF that were all snow, that’s up to 4″.
12z WRF-GFS gives us .20-.30″ precipitation and our RPM has around .30″. Basically all models are giving us enough for 2-4″ of snow…assuming there is not a widespread switchover to freezing rain or ice pellets. The WRF-GFS says only a narrow tongue of warmer air moves up the east side of the valley, keeping the mid Willamette Valley in the snow all day too.
For the purposes of the Oregon AMS “first snow” contest we do at the Winter Weather Conference each year, it finally happened this morning. The first observation of snow at PDX was at 7am. Technically 6:53am. Notice the -S means LIGHT SNOW. If you chose January 3rd, you are a winner! I’m not, I chose NO SNOW. Always a good bet generally, but apparently not this year.