I hope all of you are safe and at some semblance of peace.  This has been a very tough 3 weeks for all of us, and we still have at least 6-8 weeks of isolation ahead.  The weather has been cooperating with our social distancing regime for the past 10 days: it’s been consistently cool, cloudy and damp in the Pacific Northwest.

The month of March ended up nearly 2 degrees colder than the 1981-2010 average.  It was the coolest March since 2012!  But not nearly as wet.  We actually had a lot of dry and sunny days in the first 3 weeks.  But it never got extremely warm here; we only pulled off one day above 65 degrees.  Nights were also chilly even during the nice periods.  In fact, our averaged nighttime low temps were actually colder in March than they were in January, for an unprecedented THIRD year in a row!

I’m not sure what’s happening, but it appears that we’re getting more late-season Canadian airmasses than we used to.  Each of the last 4 years has seen some kind of chilly pattern after Valentine’s Day, and the last 3 seasons saw actual modified arctic air in the Columbia Basin, at some point after mid-February.  (Could this have something to do with an amplified jet stream?)

On to April. It was a chilly start to the month, with cold showers and snow levels down to 1,500 feet, even slightly lower in spots.  My friend Andrew Johnson took this photo early this morning, of snow near Silverton, Oregon at 1,600′ elevation:

The high Cascades just wrapped up their 2nd biggest snowstorm of the season, with 3 feet falling on some slopes.

Here in Portland it was in the 40s almost the entire day. I’m not yet sure if our official high will be 49 or 50; that won’t be known until 11pm tonight.  Either way, it’s roughly 10 degrees below normal for the beginning of April.

Staying below 50 all day in April is tough; you need a chilly airmass plus solid clouds/rain for most of the day.  High temps below 50 are not unheard of for PDX, but they aren’t commonplace.  Here is a chart tallying all the sub-50 days at the airport since 2000:

Sub-50 days don’t occur every April, for sure.  And it’s very unusual to get more than 1 or 2 such days.  Even the super-cold April of 2011, had only one day in the 40s.    The most sub-50 April days was 7 in 1955.  Cold April weather was a little more frequent prior to about 1975 in our area, it seems.

Here is another NOWdata chart showing the average date for the last sub-50 day of spring (and the first of the fall):

As you can see, the March 23 average suggests April 40s are somewhat the exception to the rule, at least in the last two decades.  Notice how nearly every year has a sub-50 in March; that Feb. 2 in 2015 was truly unprecedented.

Looking ahead…we have two more days of chilly unsettled air overhead, with the possibility of intermittent showers.  If we didn’t stay below 50 today,  we have a couple more shots to pull it off.  Temps moderate a little bit Saturday and Sunday.  Then the last two GFS spaghetti runs show some disagreement.  Both the 12z and 18z show milder and drier conditions next week for a few days.  But the 12z gives us at least a couple warm (65-70) days before sliding back toward cool.  The 18z gets us into the low 60s next week,  but turns nasty cold again in the long range.  Snow levels back down into the coast ranges as we head toward the middle of the month.  D’oh!

In general, the overall pattern remains cool.  Both models suggest a bunch more days in the 50s after next Wednesday.

It’s not a bad deal.  Mostly gray and chilly no doubt.  But we appear to get a little break next week, when we might be able to get out in the garden or go on a safe-distance walk or jog.  Hopefully we get nice weather later in the spring and in summer, when we may be allowed to go out just a little bit once again.

In the short term..keep the jackets and hot coffee handy for the next two days! -Karl