Warm Friday, Then March Starts Chilly!

I didn’t take a long vacation, just 5-6 days, but apparently there was some excitement while I was gone.  Models (mainly the GFS and for about 2 days) showed a big arctic blast for the first weekend of March.  But now we’re back to reality and I’m working again.  Here are a few highlights:

1. Friday looks great!  Offshore flow on the last day of February with at least partly cloudy skies means 50s and maybe even a few places west of the Cascades around 60.

2. Colder east wind starts blowing tomorrow night and continues through at least Sunday morning.  It’s going to be colder and it’ll FEEL a lot colder than Friday.

3.  IF we get some sort of frozen precipitation west of the Cascades this weekend (snow, sleet, or freezing rain), it will only be cold enough from late Saturday evening through Sunday morning.  Keep in mind that it’s extremely rare to get freezing rain in March in Portland.  In fact I haven’t seen it this late in the season in my 22 years of forecasting in Portland.

4.   If you live at the Coast, or south of the metro area (Wilsonville south to Eugene), forget about anything frozen…too mild.

5.  If you live in the Gorge, snow or freezing rain could linger until Monday morning.  This might be a rare early March ice storm there.  I’ve only seen freezing rain once in 22 years of forecasting here in the Columbia River Gorge.

6.  My gut feeling?  Our forecast models are likely overplaying the cold air that will come down from the north tomorrow night and Saturday and the metro area won’t see anything frozen.  Also I feel at this time that it won’t be a “major” snow/ice event in the Gorge, but just unusually late in the season.

I’ve looked at all the 00z models this evening.  And after several poor performances by the GFS and WRF-GFS the past few months, I finally broke down today and decided to try the ECMWF products over at WeatherBELL.  Quite a bit more detail on those than I get from my data provider.  I think it’ll be worth the $180/year…especially if I can get the boss to cover that!  Anyway, the ECMWF never went as crazy with the cold air to start with since it showed the upper level low sliding down through Western Canada, then retrograding out to the west as westerly flow returned back over us.    Once again, it just does a better job in general than the GFS and apparently that disparity is about to become even more pronounced.  Cliff Mass had an excellent blog post this week pointing out the disappointing developments in numerical weather modeling.  Basically the ECMWF is going to be getting a resolution increase, thus the GFS will be left even farther behind with no sign of improvement here in the USA.

Tomorrow looks excellent with offshore flow picking up during the day, but no significant advection of cold air from the northeast yet.  Hard to believe it’s the last day of February, but mild offshore flow and mostly sunny skies should push us well into the 50s.  Assuming cloud cover doesn’t thicken too quickly, some spots will get up around 60.

Then tomorrow night and Saturday models say the cold air from the big arctic high over Alberta surges south into Eastern Washington and is drawn into the Columbia River Gorge.  This is where I think models are being too aggressive with the cold air.  There’s very little upper-level support.  Consider that in each arctic air event this winter (all two), models overdid the initial push of cold air, and they were too fast both times as well.    Take a look at the WRF-GFS for 7am Saturday.  I find it extremely hard to believe that it’ll be 13 degrees at 2,000′ at the eastern end of the Columbia River Gorge in this setup.  That same model shows a HIGH of 34 Saturday…no, it’s unlikely that we’ll even get BELOW 34 Saturday morning since the wind will probably pick up during the night.

wa_2000_snow.39.0000

I did notice the 00z WRF-GFS is slightly warmer than the 12z GFS from earlier today; only a couple of degrees, but it’s headed in the right direction.  Our RPM is especially uneventful for the whole weekend.  Note the high of 42 Saturday and mid-upper 40s late Sunday as the milder southerly wind kicks in.  Also notice how it’s pretty much dry through Sunday afternoon.  But, this model has been a star performer so far this winter:

web_RPM_Text_00z_PDX

As a result, my 7 Day forecast didn’t go as cold as some models would suggest; but similar to the ECMWF, showing temps hovering within a few degrees of 40 from late Friday night through Saturday afternoon.  Then Saturday night is our chance for snow or freezing rain assuming more moisture shows up than either the WRF-GFS, GFS, or RPM show.  The ECMWF was much juicier from later Saturday through early Sunday and I’m trusting that one more.

By Sunday afternoon the cold air is disappearing as a weak southerly flow starts in the valley.  And Monday we should actually have a breezy south wind; pushing temps well into the 40s.  This is assuming models ARE too aggressive with the cold to start with.

We’ll see tomorrow if models back off on the cold air a bit further or not; another good 24 hours of model riding!

By the way, would you people prodding each other in the comments a couple of days ago knock it off?  Again…40+ year old guys acting like its middle school.  Amazing.

Chief Meteorologist Mark Nelsen

37 Responses to Warm Friday, Then March Starts Chilly!

  1. Jason Hougak says:

    February was awesome. I’d rank it in 2nd place after 1993. Interesting to look at PDX temps. 6th- 10th had lows right near record. Did the 7th and 8th set record lows? Thanks February for all the fun in the snow both with the kids playing in the backyard to hitting up the slopes. Until next year… goodbye! 😉

  2. EY (Oak Grove) says:

    I’m going to go out on a limb and say that this has been the best February since the turn of the century. We had above average rainfall, a couple mild days with one false spring day; on top of record cold and amazing snowfall.

    Had we got two 60 degree false spring days this month, I would have said it was darn near a perfect February. But I’m insanely pleased with this month!

  3. WEATHERDAN says:

    61 and partly sunny in Salem at 2:00 PM. First time over 60 in 2014. Sunset tomorrow is 6:00 PM. Some shrubs are already starting to turn green. Next October Mark will have quite a lot to summarize (meow) at the what will Winter weather weather be like meeting at OMSI. As some of you remember at the last meeting Mark was the victim of a practical joke in which every time he turned a page on his powerpoint presentation you could hear a cat going meow. Seldom do we have so much going on here as we had this Winter. Now I am looking forward to what I hope will be a normal Spring. Pete Parsons is calling for a chilly but mainly dry Spring. I hope he is wrong. But he sure got this Winter spot on. Time to drag out the barbeque. Peace.

  4. Garron near Washington Square says:

    This is our “false” spring day. 100% chance of snow for this weekend now! Currently 60 degrees outside, I’ve got windows opened, shorts on, and BBQ warming. That’s how I know we’re going to get about 6″ of snow this weekend, cause this just has to be a dream. I’ll wake up tomorrow to cold and snow, followed by 6 more weeks of rain. ( I love snow), but give me a taste of weather like this and I’m ready to string about 6 months of days like these together.

  5. Sifton says:

    OH YEAH!! 60 degrees, rum & cokes @ 1:00pm & some nice marinated pork for the Q this afternoon! Loving this spring tease!!!

  6. WEATHERDAN says:

    What a nice day outside. Sunny and 55 in Salem right now. A lot of flowers are blooming right now. Spring is almost here. We sure had a great Winter in Salem. Over 20 inches of snow and a Winter low of 8 degrees. Nothing to complain about whatsoever. Saw an exhibition baseball game on tv last night so I know Spring is right around the corner. It sure feels like it today. Aloha Mark.Peace.

  7. paulbeugene says:

    50F, dewpoint 22 at Bellingham right now, an arctic front with pressure gradient but no real cold air with it…yet. Spokane 35F/dewpt 28 NE winds too. They will probably get cold, eventually.
    Time to get out the fork graphic and stick it.

    Mark: nice to see you shelled out the same cold hard cash I did to get weatherbell subscription. The graphics are great although they took out some of the numerical output overlay (previously you could see how many inches of snow would fall at the official stations). I imagine it is only a matter of time before they add the Portland metro Euro high res output map.

  8. JohnD says:

    Spokane is a large Pacific NW city that hardly is
    ever mentioned–and often a wintry one. A good index
    point to ponder as well. They will be having bitter
    cold and copious snow there this weekend.

  9. pappoose in scappoose says:

    HOW MUCH COLD AIR WILL REALLY MAKE IT INTO THE GORGE?

    Pretty sure the only way to answer this question at this stage of the game, is to ASK THE MAGIC 8 EIGHT BALL!

    http://www.magic8ballonline.com/8ball/index.cfm?go=yes

    NATIONAL WEATHER SERVICE PORTLAND OR
    906 AM PST FRI FEB 28 2014

    MODELS HAVE BEEN ALL OVER THE PLACE DEALING WITH THIS COLD AIR. THE NAM CONTINUES TO BE THE MOST AGGRESSIVE WITH THE COLD AIR…WITH THE GFS THE LEAST COLD AND THE ECMWF SOMEWHERE IN THE MIDDLE. OFFSHORE LOW-LEVEL FLOW RETURNS LATE TONIGHT…BUT WILL BE MORE APPARENT SAT. NAM INDICATES NEARLY -10 MB KTTD-KDLS 18Z SAT…SIMILAR TO THE LAST OFFSHORE EPISODE EARLIER THIS WEEK.

    THIS WILL BRING ANOTHER ROUND OF VERY BRISK EAST WINDS TO THE AREA AGAIN…ESPECIALLY IN AND AROUND THE GORGE AND NEAR PORTLAND. WILL LIKELY NEED A WIND ADVISORY FOR THIS SITUATION AT SOME POINT. BIGGEST FORECAST CHALLENGE SAT WILL BE PRECIP TYPE FOR THE GORGE. STILL NOT CONVINCED IT WILL BE ALL THAT COLD. NAM SOUNDING FOR KPDX VALID 15Z SAT SHOWS A SFC TEMP OF ABOUT 28F WITH THE SNOW AS THE MAIN PRECIP TYPE. THIS MODEL MAINTAINS A SUB-FREEZING SFC LAYER THROUGH SUN MORNING. THE GFS AND THE ECMWF ARE NOT NEARLY AS COLD. GFS SOUNDING FOR KPDX KEEPS THE SFC AND WET-BULB TEMPS ABOVE FREEZING SAT. ANOTHER FACTOR WORKING AGAINST THE COLD AIR IS THAT THE MAIN COLD LOW TO OUR NORTH STAYS TO THE NORTH AND DOES NOT PROVIDE MUCH UPPER LEVEL SUPPORT FOR DRIVING THE COLD AIR INTO OUR AREA. THE DENSITY OF THE COLD AIR SHOULD BE ENOUGH TO ALLOW IT TO SAG SOUTHWARD AND INCREASE THE EAST WIND IN THE GORGE AS EXPECTED. BUT…HOW MUCH COLD AIR WILL REALLY MAKE IT INTO THE GORGE?

  10. Even NWS finally backed off on the snowpocalypse finally this morning. Welcome home btw Mark.

  11. Hal in Aims says:

    breezy out of the east here all morning………power went out about 25 minutes ago…….on generator now…….again……….sigh…..

  12. gidrons says:

    Cliff’s blog was an eye opener, and blood boiler.

  13. Ben T says:

    Poose you in!!?

    • pappoose in scappoose says:

      I’m in!

      I must admit, the middle school prodding was really funny/had me laughing (hard) this last go-around.

      Not trying to pick on you W7, but the smarty pants line was absolutely enough to put me into uncontrolled hysterical laughter!

      Amazing for sure.

  14. Jason Hougak says:

    I’m praying that this year we get some awesome thunderstorms. Nothing like a good thunderstorm weather watching. Only thing I’ve ever seen is snow thunderstorms. What if there were snow hurricanes or tornados!

  15. Jason Hougak says:

    The classroom of weather nerds who never grew up or at least wanted to. Heck that’s half the reason I love snow so much right.
    ” I don’t wanna grow up a snowsRus kid!”
    Congrats Mark on your safe trip home, hope you and the fam had a wonderful time!
    Also I don’t know what the fuss is about, it’s all in good fun. Come on we are weather nerds complaining to each other or enjoying the same weather. I like snow, I like rain, I like sun, I like cold, I like hot…

  16. alohabb says:

    What island Mark? Im taking my first trip to Oahu in June after only going to Maui.

  17. schmit44 says:

    2/27/2014 Oregon (All) Temperature Summary

    Warmest:
    High:62 at PROVOLT SEED ORC(1180 ft) & MT. YONCALLA(1822 ft) & EW0059 Myrtle Po(174 ft) & CW6811 Grants Pa(947 ft) & BUCKHORN SPRINGS(2780 ft)

    Low: 51 at BROOKINGS(79 ft)

    Coldest:
    High:32 at CALIMUS(6629 ft) & Rim(7050 ft)
    Low: 24 at MT. WILSON (4002 ft ) & Blue Box Pass (U (4024 ft ) & EW4395 Milton Fr (3455 ft )

    Largest Diurnal Change: 26 degrees
    MT. YONCALLA (62/36 ) (1822 ft )

    Heaviest Rainfall:
    0.54″ at YELLOWSTONE MTN.(3080ft)
    0.44″ at KNF91 PORTABLE(3343ft)
    0.44″ at QUAIL PRAIRIE LO(3183ft)

  18. Rob - Southeast Portland says:

    Thanks for the very thorough and detailed update, The ‘Master Clipper?’ …. Chief Snipperologist, Mark Nelsen.

    • Rob - Southeast Portland says:

      The models and Mark are likely correct, but I’ll still monitor surface observations throughout the Columbia Basin, northerly gradients between OMK-YKA, PDT-OMK, dewpoints to see if they are falling, PDX-DLS gradient, and upper air temps just to see how much cold air is or isn’t progressing southward.

    • pappoose in scappoose says:

      Win, lose, or draw with the cold, it’ll be fun to track!

  19. W7ENK says:

    Welcome home, Mark. I’m jealous, I’ve never been to Hawai’i. One of these days, I’ll get out there.

    I had an overwhelming suspicion that the models would yank the rug out from under us just around the time you came home, though it happened about a day earlier than I had expected. You should have stayed until Sunday, then it would have snowed here for sure!!

    Funny how that works… o_O

    • Benjamin (West Salem) says:

      Yeah.. the GFS took us on another wild ride that seems to be ending how most of our rides end….with very little weather excitement happening. Time to stick a fork in it??? I’m ready to start watching for that one (if we’re lucky) a year thunderstorm to roll up from the SE. Who knows? We scored big time this year with snow, maybe we’ll get several T storms?? 🙂

  20. Seahawks Fan - NE Vancouver says:

    Those people “prodding” must be bored in their mother’s basement. Hopefully they realize their behavior is providing guilty entertainment to the rest of us. Just because you’re 40+ years old and/or “manage” a private Facebook group doesn’t make you better or more intelligent than the next person. No need to put on a front that your poo don’t stink. Some need a reality check and quick.

    • Rob - Southeast Portland says:

      Not sure who you are but the only ones running Facebook groups are myself and Brian Schmit. I know you can’t be referring to me as I believe I only commented twice rather harmlessly? and the rest was just analysis. I was however bashed and my name repeatedly mentioned even when I wasn’t posting anything. I also don’t believe Brian chimed in any if at all. I guess that means you don’t know what you’re talking about and are merely trolling yourself. I’m not here for entertainment unless it’s practical or perhaps Boring Larry’s haikus, maybe Pappoose’s YOU IN!, here to do analysis or read others thoughts and weather discussion.

    • vernonia1 says:

      Rob.. I think he might have been referring to Mark?? oops! not good 🙂

    • vernonia1 says:

      well guess I needed more coffee…did not read seahawks post correctly 😦

    • Mark Nelsen says:

      My poo still stinks

    • pappoose in scappoose says:

      Wait…let me check…So does mine! Hahaah!

  21. boydo3 N Albany says:

    Already had a couple 60 deg days here. I’ll bet the offshore winds keep us cool tomorrow tho. Got fog here already tonite.

  22. Lurkyloo says:

    Hope you had a nice vacation, Mark. What’s the saying? “The kids will play when the blog-master is away?” Yeah, that’s it …

    • Fred Vandecoevering says:

      Hey Mark, really like your blog. From one Monitor guy to another! But I am still out here.

  23. schmit44 says:

    Can’t wait for that first 60 degree day this March. Looks like I will be waiting a while.

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