As mentioned in the midday post, sure enough a mild southerly wind developed and is keeping about 1/2 of the metro area south of the Columbia River and West Hills well above freezing.
That warmer part of the metro has only seen a snow/rain mix or just plain rain depending on your location. Lack of that mild wind has brought 1/2″ to 1″ in areas around Scappose, St. Helens, and earlier around Battle Ground, all on the north side of the metro area. La Center (at 600′) picked up 3″ so far. Now I see I-84 covered in snow east of I-205.
And now some good news if you want real snow. That will be the maximum extent of the southerly wind. From here on out through the night it backs off. Right now easterly flow is picking up through the Gorge. It’s snowing in much of the eastern metro area. That includes Happy Valley, Gresham, Camas, Troutdale, Damascus, and Oregon City. Remember that ECMWF model I showed earlier (and other models) had the cold easterly wind taking over after 10pm or so, that should change much of the metro area over to snow as we head toward midnight and beyond.
Our forecast remains the same for all areas. No need to update any of these
The final model run (before this event) of WRF-GFS from UW show just about the same thing, some areas of 2″+ snow in metro. But most areas less than 2″ (or even less) in the Willamette Valley.
HRRR model is somewhat similar with some parts of metro getting less than 2″ out of this event.
We’ll see how it ends up overnight. The main change will be increasing cold easterly wind blowing out of the Gorge bringing some drifting snow east of I-205 and eventually into the West Hills too by morning.
QUICK LOOK AHEAD
There has been lots of talk about a possible snow event Sunday night and Monday. There is no guarantee that’s going to happen. In fact both the evening GEM and GFS models put is into a mild southerly wind from later Sunday night through Tuesday. That could possibly leave the Willamette Valley and Portland metro area with mainly rain through that event. After we finish up this event tomorrow afternoon I’ll take a closer look at that of course. No reason to get all wound up about a third snow event that may not even happen!
Chief Meteorologist Mark Nelsen