February 7, 2019
Now we’re within a couple of days of a Friday night and Saturday “snow event” so it’s time to put out a few numbers. I’ll make this posting quite a bit briefer than yesterday’s. BTW, I know we have an issue with readability on mobile devices…we’re working on it.
At this point it looks to me that at least PART (if not all) of the metro area will be getting “sleddable” snow from late Friday night through Saturday evening, when we dry out. By that I mean at least 2″ snow.
HOW MUCH SNOW COULD FALL?
(this is between Friday night and Saturday evening, subject to change in the next 36 hours as we get new info)
PORTLAND METRO UP TO LONGVIEW 1-4″, most near Gorge & Clark County, least south & west metro.
SOUTH OF METRO DOWN TO ALBANY Trace-2″, most likely not anything Friday night, a bit too warm
NORTH OREGON & S.W. WASHINGTON COAST Trace-2″, highest total up around Cannon Beach to Long Beach
COLUMBIA RIVER GORGE 3-6″, This is from Corbett/Mt. Pleasant areas eastward. A typical east-wind driven snow; expect blowing/drifting snow entire west end. Cold, windy, and snowy!
THE GENERAL PLAN
Models are in a bit better agreement today, at least the dependable WRF, ECMWF, and GEM. America’s pride, the GFS model, appears to be out to lunch. Too warm and it produces little to no snow through Monday! Our RPM model takes its input from that GFS so you see it isn’t doing much either
The GEM, not shown here is “wetter”, producing more like 3-6″ snowfall all the way from Longview to Eugene. I’ve ignored that for now as well.
Precipitation arrives Friday evening in the valleys, and at that point it’ll be maybe 5 degrees too warm for sticking snow, except near the Gorge where evaporative cooling and leftover east wind will keep temps at/below freezing
ALL models show that we wake up to snow showers Saturday morning, with the WRF and ECMWF already spreading cold (below freezing) air through the central/east metro.
All models also agree that anything wet freezes solid Saturday evening, regardless of how much snow we get, or don’t get. EXPECT ICY/SNOWY ROADS SATURDAY NIGHT AND AT LEAST THE FIRST HALF OF SUNDAY
STILL ONE HUGE “UNKNOWN” AT THIS POINT
- Do we just get scattered light snow showers Saturday? Just one inch? If so, then metro area roads could remain in good shape due to strengthening February sun energy keeping pavement temps above freezing
- OR…is it steady snowfall, freezing up metro roads right away in the morning as the cold east wind arrives? If so, that’s a real snowstorm (several inches) and traffic grinds to a halt right away or during the day in our area. That would include blowing and drifting snow in the east metro and hills.
I know many of you have events on Saturday and it’s a tough call. I’m leaning toward at least the central/east half of metro turning snowy/icy during the day or even starting out that way at daybreak. I do feel pretty confident that from Wilsonville south there’s a decent chance roads are just fine until late in the day. ‘ll have a better idea tomorrow.
WHAT HAPPENS AFTER A FROZEN SUNDAY MORNING?
- NO SNOW, A DRY DAY A very slow thaw on some roads, but shady areas and hills stay locked in ice.
- Cold east wind keeps us mainly frozen through the middle of next week!
- A 2nd system arrives Sunday night and continues through Monday morning. We could see at least 2″ with this one, possibly more. Yes, Monday morning we will likely be locked in a beautiful white coating of snow across the entire metro area.
- This is crazy, but a THIRD system with possibly a lot more moisture runs right over the cold east wind Monday night and Tuesday. Models are all over the place with this one. Anything from just light snow up to many inches.
THIS COULD BE A HISTORIC & SNOWY 5 DAY STRETCH FOR THE MONTH OF FEBRUARY IN NORTHWEST OREGON AND SOUTHWEST WASHINGTON