Here we are in the last few days of January; time is flying! It’ll go down as a mild and uneventful month…after that stormy/rainy first week.
MY THOUGHTS ABOUT THIS WINTER SO FAR
- Temperatures have been about normal. Warm November, Cool December, then slightly warm January. Nothing real interesting.
- Precipitation is still above normal for this water season that starts October 1st. Right now PDX is just a touch under a typical January rain-wise. But rain/showers Sunday & Monday should put us just a bit above average for this month. We haven’t had a drier than average month since August!
- Snowpack is running near normal for late January across most of Oregon. But it’s still well above average in the northern/central Oregon Cascades. If we want to get out of the drought still plaguing much of the state, we’re going to need a wet/snowy February and March! Just “average” isn’t going to cut it.
- Those 7 days at the end of December were fun with snow at times in the lowlands, but outside of that we haven’t seen any more snow or freezing rain.
- There’s no sign of a big arctic freeze or widespread lowland snow through the first week of February
- Stormy weather (strong south wind or heavy rain) is unlikely in the next 10 days
- Most likely we’ll be drier than normal the next 10 days
You can see the stats for PDX this water year…a bit under 2 FEET of rain this season so far
About double that at Astoria, around 4 FEET of rain
Lots of that was “warm” rain in October, November, and early January. So snowpack about average now across much of Oregon, but better up in NW corner
The weather pattern is relatively straightforward this last week of January and into first few days of February. Big upper-level ridge overhead has been keeping us dry. Warm mountains/beaches and cool (normal) valleys. Please appreciate the nice 1st grade quality annotations I’ve put on these maps.
By late this Saturday the ridge has weakened and a cool trough (dip in jet stream) is approaching
By late Monday a transition has occurred. The ridge wants to pop up again just west of the West Coast. This is a cool-ish pattern for us; a cold trough is dropping through the Pacific Northwest.
Snow levels will crash Sunday through Tuesday. For the weather geeks, 850mb temps down around -5 to -6 Monday/Tuesday. If there are still showers around, a dusting is possible above 1,000′ during that time.
Finally some snow in the Cascades!
Models have been waffling around a bit about what occurs those first few days of February. The ECMWF and GEM have been insistent on keeping the ridging nearby for a drier than normal weather pattern the first week of February. The GFS (surprise!) keeps wanting to dig a cold trough south over us at some point next week, down the back side of the ridge. Notice the difference in placement of the upper-level height anomaly. GEM/ECMWF look like this for February 1st-7th. Mild and drier than normal
ECMWF is especially pathetic with lowland snow, giving us almost no chance through February 8th
Meanwhile, look at the GFS keeping ridging a bit farther west the first week of February. Still drier than normal, but some cold troughs would swing much closer to us for a very cold Rockies/Central USA
That’s it for now. Enjoy the fog/sun mix the next few days!
Chief Meteorologist Mark Nelsen