Evening models are all in and they are all exactly the same, which gives us pretty good confidence on the forecast.
What has changed this evening?
- All models push a band of light rain (freezing rain) across the west side of Oregon right between 4-7am instead of waiting until mid-late morning. TIMING HAS SPEEDED UP
- This means most roads will have a fresh glaze of ice on them for the morning commute from Longview to Eugene. I’d forget the morning commute if you live in the I-5 corridor.
- I’m increasingly confident that most areas on the 3 maps down below will see gradual melting in the afternoon and be pretty much “out of the woods” for the evening commute. If you’re not in the blue area BELOW, things look much better by afternoon/evening. Click through those 3 for a closer look.
- East wind is even STRONGER this evening! Peak gust this past hour 89 mph at Vista House and 83 mph at Corbett. In the past 18 years I’ve never seen winds up in the 75-85 mph range in that 2nd location for more than a brief blip. Crazy.
- A major and possibly crippling ice storm is BECOMING LIKELY in the central/east metro area similar to the 1996 event starting tomorrow afternoon and continuing through sometime Wednesday AM/midday
- The Columbia River Gorge (all of it) is LIKELY to see a major/crippling ice storm tomorrow through Wednesday. This on top of heavy snow/ice already could lead to roof collapses in that area.
- The low-level airmass doesn’t change at all through Tuesday AM as frigid air keeps pouring out of the Gorge. We remain below freezing in most of the Portland area.
- A band of rain moves through most areas west of the Cascades between 6-9am, freezing on contact in almost all areas in the western valleys of Oregon/SW Washington
- Roads in most of the metro area (that aren’t already icy) will turn icy within 15 minutes of the rain arrival
- Then mainly dry for a few hours and temperatures everywhere except central/east Portland the Gorge rise to near or above freezing.
- Temps remain in the 20s East Portland to around the Gorge entrance…solidly frozen all day there.
- Heavy rain arrives around 3-4pm and it pours all night long into Wednesday AM as a brief “pineapple express” parks itself overhead
- West and south metro plus Clark county should be slightly above freezing during this time, thus avoiding a big ice storm.
- DURING THIS PERIOD, EAST PORTLAND OUT TO THE GORGE LIKELY REMAINS BELOW FREEZING
- If models are correct, 1-2″ ice could form on all exposed surfaces, doing tremendous damage to trees/powerlines that we haven’t seen in 20 years.
- Any precipitation through Wednesday midday/afternoon should be freezing rain in the Gorge. 1-2″+ is likely out there.
- I’d say both should be skipped tomorrow
- Check right away in the morning when you get up to see how temperatures are doing and where the precipitation is of course. Maybe I’ll be totally wrong this time and we’ll get lucky!
Chief Meteorologist Mark Nelsen