Better Chance for Sticking Snow Saturday Morning in Metro Area

March 13, 2020

7pm Friday…

It was nice to see snowflakes this morning.  I was driving through Gresham taking care of errands and it was dumping snow…at 37 degrees around 11am.  By the time I got home at 1,000′ there was maybe 1/4 to 1/2″ on the ground.  Then showers tapered off; exciting while it lasted.  By the way, in my “Winter is Over” blog post three weeks ago I mentioned this setup.  It can still happen this late in the season

Mark Winter is Over3

Tomorrow more of us will see sticking snow during the morning hours.  Even some low elevation spots could see enough for some quick sledding (1″ or so…low standards in Portland).   Others?  Wake up to nothing.  No matter what happens the first half of the day, the 2nd half will be like today.  Partly to mostly cloudy with temperatures reaching the low-mid 40s.

We don’t expect any sort of widespread “life-altering” snowfall west of the Cascades in the I-5 corridor tomorrow.  This is the forecast graphic I’m using this evening:

Snow Cold Look Ahead End of Event

Why such a wide range?  Zero to 2″????  There’s good reason for that.  We’re talking scattered showers late tonight through about noon tomorrow.  If you are under a heavy shower, an inch could suddenly accumulate.  If those heavy showers miss you?  Little or nothing accumulates.   For Example: In this pattern, someone that gets dumped on near the Columbia River (~ sea level) could get an inch or two.  But another location up around 1,000′ that misses out on the showers gets only a trace!  It’s not just about elevation.  That said, colder temps up in the hills do give a better chance for “sleddable” snow there.

Snow Cold Look Ahead End of Event2

Technical Talk

Colder and very dry air is surging south through eastern Washington this evening; by sunrise it should be pouring out of the Gorge and into the metro area.  That airmass has Even though temps with this will probably be up around 36-40 degrees, any precipitation falling into the very dry airmass will bring temps down to near freezing.  That’s the 2nd reason we have a better chance for sticking snow tomorrow morning along with precipitation intensity.

Models are looking a bit more consistent this evening.  Most giving us very light snowfall, only a trace to 1″ generally.

Snow Model Accumulation Several

So in the end I think this will be another “non-event” like what we saw Thanksgiving Weekend, mid-January, and early February.  Just a little here and there.

We do have some fantastic early spring weather coming back for early next week.  Check out the high temperature forecast for Portland.  Some nice stuff ahead…get outside and enjoy the sunshine.

Data Driven Forecast Highs Next 7 Day Meteogram

Chief Meteorologist Mark Nelsen