This is what I’m showing tonight on the 10/11pm shows:
- Precipitation will arrive in the next few hours in the Gorge. It should begin as snow in the central/eastern parts and eventually (by late tonight) work it’s way down to water level (I-84). Down along the freeway 4-8″ snow is possible from Cascade Locks to Hood River, a bit lighter farther east. Where the snow sticks immediately up around 1,000′ or so, 8-12″ could fall.
- The cold air will be thin and just barely down to around freezing in the western Gorge. It’s quite possible I-84 remains clear west of Cascade Locks with freezing rain confined to only areas up around 1,000′ in Cape Horn & Corbett areas.
- Temperatures will not warm until late Thursday night with a westerly surge through the Gorge.
One concern leading up to this event has been that models could be overdoing the cold and/or dry air coming in from the north and east. I just compared this evening’s WRF-GFS model meteograms with last night’s run. A very slight warming…we’re talking maybe 2 degrees. But that could be enough to make quite a difference in ice and snow accumulations. That should also keep freezing rain above the freeway west of Cascade Locks. I can’t remember a time where it was 40 degrees at Vista House with no significantly colder air to the east, yet freezing rain is supposedly only 4-6 hours away. Hood River and The Dalles in the upper 30s with drier air is better for marginal snow accumulation temps there; that’s why I kept pretty much the same accumulation forecast I initially showed earlier.
There WILL be isolated spots in the western/central Gorge that see quite an ice storm; but it won’t be down on the freeway.
We’ll know for sure by 4am or so, once the evaporational cooling drops temps.
For the metro area…whew, another big soaker coming. I doubt we’ll see the huge 1-2 hour downpours that caused all the trouble earlier this month. But a solid 2-3″ of rain the two days is sure going to bring us more mudslide and landslide issues.
Chief Meteorologist Mark Nelsen