Sunday Evening Update

Well, isn’t this getting interesting?  At 8pm we can see snow coming down at 1,800′ on our KPTV tower and snowflakes mixed in with the rain on our Fox Tower Camera (450′).  Temperatures are falling steadily due not to radiational cooling, but cold air pouring inland.  But first a scolding about "wishcasting".  In forecasting class up at the UW we were taught to be very careful about this…you really want something to happen (snow) so your forecast basically veers towards what you want to see.  There was a ton of this on the comments the last 24 hours.  Many of you were convinced the low was headed into Oregon even though EVERY SINGLE model showed it moving inland somewhere either in Western Washington (GFS, ECMWF, MM5) or Vancouver Island (NAM).  In the end the GFS-MM5 from the UW once again NAILED it with a passage around Hoquiam then inland to Seattle.  I for one am amazed the model can do so well.  If 2 weeks ago before the windstorm I would have suggested the low was heading into Newport instead of Hoquiam, I would have been laughed off the blog.  My forecast would have been for light north wind instead of gusty east wind.  So why was the "snow low" different?  It wasn’t  and the main reason many were expecting it to go south was because they (I too) would really like to see snow.  So my point is to watch out in the future, but there’s nothing wrong with speculating on possibilities either.

Forecast tonight/tomorrow is pretty simple…very cold onshore flow continues until late tomorrow evening.  Snow levels are down to around 1000′ right now and will hover between sea level and 1000′ through tomorrow.  That means anyone COULD see snow, but it’s far more likely as you go up in elevation.  There doesn’t appear to be a ton of moisture, but 2-4" at/above 1000′ seems safe.  A heavy shower band could dump 1" even to sea level but that’ll be tough to do during the daytime.  Some sort of dying "arctic front" seems to come through here tomorrow evening, then it’s on to dry offshore flow for Wednesday.  Gorge winds kick in Tuesday night.  That gives us a chilly 35 or so (with sunshine) Wednesday. 

00z GFS is insistent on busting a weak system inland Wednesday night or Thursday morning.  Obviously that’s either a snow or freezing rain producer.  It won’t be a prolonged event because the low is going by to the north as it passes through Canada, unlike our ice storms where a low swings by to the west and then moves offshore again…Mark

697 Responses to Sunday Evening Update

  1. -100F says:

    Ryan, that was what Rod Hill wrote at 6 AM, I think he may have changed his forcast by now.

  2. Matthias - North Portland says:

    Mark posted a new blog entry…check it out.

  3. alex says:

    i only went up about half way with my older sister.

  4. alex says:

    once you head in to the high hills (700-900′) you will praably see about 1-2″ their i had a digital thermoter (like the one on kptv) got it up their and it said 28.5 degrees!! any snow that falls in the hills will stick same down here (400-500′)

  5. AKB-tigard says:

    im actually pretty warm compared to you guys. im at 35.2. a shower is heade towards me so taht should drop quik. actually its perfect timing it will hit when its getting darker to really put the temp down there. i hope for a very thick freeze to get a late start at school!!!!!!

  6. Ryan says:

    I just read the latest text from Rod Hills forecast on the K2 website. He noted that showers should continue into Tuesday morning dropping as much as 1 to 4 inches overnight down to 300′.

  7. Jesse says:

    Down to 33 in Orchards now, there is still some light snow on the roof and cars from the last flurry. I drove up to my Grandpa’s house in The Heights at 300 ft by David Douglas Park, about a half inch of snow there, grass, roofs and cars were covered and road was slushy, I’m sure its frozen now. I don’t understand any pessimism about more showers. We are all rapidly approaching freezing now and I can see a lot more showers moving onshore in NWly flow. A good batch should hit the area in the next hour or so, maybe drop another inch or more depending on shower intensity. The nice thing is whatever falls will for the most part be here until sometime Thursday or later!

  8. -100F says:

    I have a feeling that shower will weaken as it heads over us.

  9. alex says:

    my trampoline(for my little sisters) is covered in white snow flakes and sleet it has been like that for the past hour or two that should freeze tonight!!

  10. alex says:

    just droped to 31.5 geting cold brrrrrrrrrrrrrrrrrrrr

  11. alex says:

    astoria is at 34 with some light snow

  12. Lyn-Canby says:

    Here in Canby we have dropped 4 degrees in 1/2 hour

  13. Camas Mom says:

    Yes! OK, going to do some stuff, will check back with you guys. light powdery snow has quit for now, but all brightness gone – never did get a sun break at all. I’m sure it’s brrrrrr cold out.

  14. alex says:

    if this is a heavy snow shower that produces 0.1″ of rain that would be a 1″ of snow….i hope my temp is kinda jumping 34.1 now my high was 37-39 i expect the temp to fall 3-4 degrees as the snow showers come in…weather channel just changed the snow adivsory to 10:15pm monday?????????? :(…but the hourly forcast has snow showers all the wat to 11am tuesday? thats wierd as the night goes we will be in the -10 to -12 area on the gfs…freezing rain on thursday maybe some snow showers mixed in with freezing rain

  15. Camas Mom says:

    light snow, getting dark. tee hee…

  16. jacob BPA says:

    Front stalling means more showers through out the night

  17. Ryan says:

    I’m sitting at about 35 degrees and steady right now with clear skies.

  18. SnowFlake says:

    Tripcheck cams show Cascade Locks getting snow (or maybe sleet?) and they’re at 210 ft…
    No snow angels over here near Bull Mtn – skies are blue. I’m being teased by the clouds in the distance ….

  19. Derek-West Gresham says:

    Here are my thoughts -100F. Right now its 33-35 for most of us. And cooling. I believe there is a decent bet this next batch comes in because of its NW trajectory, like the last one that came through. When it does I expect accumulating snow for all of us, though the lower elevations wont have much on the roads. It will get us all to freezing, or very very close. Then after that I disagree with Paul. Every station near that low that I checked is reporting light snow. So as that low moves south some light snow should come with it. The snow is only 75-100miles to our northwest. So if it can track down that far in 12 hours, which is reasonable. We could see some snow overnight. School delays likely, school closures, possible.

  20. Ryan says:

    I’m not any of the afforementioned but…..
    I’m thinking we get nothing more than the showers we are seeing now. But once we get below freezing if they keep up through late tonight and into early morning it could give us 1 to 2 inches. These cells are pretty intense when they roll through.
    I have to imagine almost everyone will have 2 hour delay for schools. Lots of water on the roads + freezing temps = nighmare commute tomorrow. Usually if there is a major freeze schools get delayed or on occasion closed.

  21. Boring Larry says:

    i’d say, that after driving around eagle creek /sandy area,that there might be some delays in the morning…there’s an ich of slush everywhere, and our temp right now is 32.7…..sounds like a big skating rink forming!!

%d bloggers like this: