A dry & mild February so far

8pm Tuesday...

It’s been a week since my last blog post, but not much has changed. Strong high pressure remains anchored just off the West Coast, blocking strong weather systems and keeping us much drier than normal. This is the 5th week that the Pacific jet stream has failed to deliver significant mountain snow or valley rain. Portland will end up with only around 1.00″ of rain during these five weeks! Quite a change after the huge soaking, flooding, and mudslides of early January.

First, a quick summary of what to expect the next 10 days (through the 18th):

1) No snow or arctic blast/cold throughout the lower elevations west of the Cascades.

2) No rain until next Monday, Valentine’s Day. Even then, next week doesn’t look very wet, just showery at times

3) Very mild days continue through Sunday, then it’s back to 40s and lower 50s next week.

4) We could see a nice dump of Cascade snow Sunday night through Tuesday, until that time it’s spring conditions

Look at the 500 millibar anomaly for January. Big ridge cozying right up against the West Coast much of the past month

That ridge is still there tomorrow, quite strong for late winter

No change through this Saturday, although it moves directly overhead. That should switch our wind-flow to gusty easterly through the Gorge, eliminating most fog & low clouds Friday through Sunday.

A fast moving upper-level trough passes through Sunday night and Monday

Then the strong ridge develops again next week, weakening late in the week. Here’s Friday the 19th. Mild and possibly wet

So...that leaves us about 2/3 of the way through February without significant rain. By the way, with some easterly wind Friday through Sunday we MIGHT be close to a record high in Portland. This time of year is tough because inversions only partially break in the valleys. 50s in the mountains would mean 70-75 in this pattern in the lowlands a month from now. But it’s only early-mid February so 65 is about the highest I would expect away from the gusty wind near/in the Gorge.

Check out the coastline! One more amazing weekend. Brookings on the southern Oregon coastline hit 77 today!

Are we done with lowland snow/ice for the winter? Most likely, but it would be risky to declare WINTER IS OVER until after Valentine’s Day. It’s VERY UNLIKELY we see any sort of all-day snow event that would really mess up your life from this point forward.

I was burned 10 years ago in late February and March 2012 (declaring winter was over too early) and I don’t want to make that mistake again. Looking back at 81 year’s worth of Portland records, here’s the chance of getting 1″ snow in the city:

If we make it to February 20th with no snow, we’re down to about a 10% chance of real snow from that point forward. I think there’s a good chance we look back and say “winter ended the 2nd week of January this year”. Of course if you live up in the hills near/above 1,000′ near either the Coast or Cascade range, there’s a much better chance you still get a few inches before April arrives.

We need LOTS of snow in the mountains from this point forward to chip away at the 2 year drought in the southern half of Oregon. Check out how low snowpack has dropped during these five dry weeks

That’s it for now. I’m leaving my snow tires on since we have a quick trip over the mountains next week and I still want to ski a few more times. But if you don’t plan to leave the lowlands over the next few weeks, it’s probably just find if you take yours off.

Chief Meteorologist Mark Nelsen