Brrr! Mark Had A Cold Bias This Summer

10pm Wednesday…

A post for the real hardcore weather groupies…

Let’s say you’re just sitting at home in…let’s say…Orchards, or Stevenson, or Tigard (pick your own town).  You’re thinking “it seems like temperatures were often warmer than forecast this summer“.

Well, you’d be right.  Just for “fun”, I made a spreadsheet with my 46 different forecast high/low temperatures from June 1st to August 31st.  Then I compared those forecasts to reality.  The red bars below in the charts represent days in which my forecast was too warm.  Blue bars mean it turned out warmer than I expected.

Yep, on the high temps I was too cool 30 days and too warm 9 days.  The rest were right on.  Notice the big spike in late June.  That was our first attempt at 100 degrees, then clouds/sprinkles moved through instead.  Oops.  But you can see the vast majority of the summer our forecasts were consistently just a few degrees too cool.  Model MOS forecasts were consistently too cool as well, so I’m quite sure the above normal sea surface temps (and lack of marine cloud formation) had a lot to do with it.



How about low temps?  It’s been another summer of record warm low temps.  These were split a bit more evenly.  There were many evenings when I went well above the MOS values knowing that models were consistently running too cool.  So I was too cool 23 nights and too warm 15.




Chief Meteorologist Mark Nelsen

73 Responses to Brrr! Mark Had A Cold Bias This Summer

  1. WEATHERDAN says:

    70 and partly sunny at 3:00 PM. Yesterday was 73. So a fairly tolerable Labor Day weekend. And no rain, which is nice for barbecues. In fact we have had no rain since last Sunday afternoon. Yes Jason I did forecast the return of nicer weather about last Thursday and it has arrived in Salem where I live. Apparently however not in Portland where it is 57 and raining at 3:00 PM. Nevertheless all areas should be warmer tomorrow. PDX and environs should see some morning for due to all the rain you have had up there. Probably not from Salem South. Though we may see some early morning low stratus. 75-80 central and South valley on Monday and 70-75 North. Maybe low 90,s by Friday or Saturday. Saw a great concert at the State Fair yesterday. Eric Burdon and the Animals who still sound great. It was clear but cool for the concert. Amazing that on last Tuesday on the channel 12 7 day forecast the predicted high was 80 which seemed very reasonable to me. Yet today it is only 57. However many times in the past such as 1968,1980, and 1998 Portland has had snow and temperatures in the 20,s and Salem was raining and around 40. So sometimes just a few miles makes a big difference in the weather. Happy Labor Day everyone. Peace.

    • WEATHERDAN says:

      72 and partly cloudy at 4:00 PM. 58 with fog at PDX. That is the biggest temperature difference I have ever seen between the two in September. The lawns in Salem are still brown. We only received .64 out of all those systems. Now we are going back to warm and dry. NWS says 80 in Salem on Tuesday so back to Summer. For a while anyway. Labor day weekend in Salem. Friday, 68/47 Partly Cloudy. Saturday,73/47 Partly Cloudy. Sunday, 74/47 Partly Cloudy. Monday, *77/46 Mostly Sunny. .Not as bad as it could have been. Peace.

    • Dave in SW PDX (235') says:

      Eric Burdon delivers every time. Love that guy.

  2. David B. says:

    0.24″ of rain here overnight. No thunderstorms.

  3. Jason Hougak says:

    Rain is pouring while it was predicted by some that it was suppose to be nice the next two weeks. Just goes to show you weather has it’s own mind and doesn’t like people or computer models more likely guessing what it’s gonna do.

    • MasterNate says:

      Just a heavy drizzle down here but sure feels great! Good coffee drinking weather.

    • David B. says:

      Actually, most models were showing a cool period lasting a week or more. We’re about to the end of it, though it’s not going to rebound to being as warm as it was before. Days are getting shorter, which heavily stacks the odds against that happening. I’ve probably seen the last of the 80s for this year.

  4. Jason Hougak says:

    Rain, cooler temps, lime, fertilizer sure does quickly green up a lawn.

  5. Longview 400 ft says:

    I have a question, “What happened to Sophie the weather girl? I have not had access to TV monitoring for over a year.

    • Boomer in Vancouver says:

      I believe she went to work at the Better Business Bureau in Public Relations.

    • geo says:

      I saw her on a news channel about two weeks ago being interviewed. Looks like she was a spokeswoman for some company if i remember correctly.

    • Longview 400 ft says:

      Thanks for the responses. I have access to channel 49 but not 12 the last couple of weeks. I am going the attenna route. Still trying to find a way to receive channel 12, I get 2, 8, 10 and all those that come with it, and 49 and 6. I was t 12 for two reasons, Mark’ weather forecast and the Seahawks are mainly televised there. Any suggestions, i’ve tried an amplifier, having my attenna at 168 degrees (which is where it is now), and a few indoor that claim to be good at 60 miles away from any transmitter.

    • W7ENK says:

      You’ll probably need a Yagi on the roof.

  6. schmit44 says:

    9/5/2015 Oregon (All) Temperature Summary

    High:76 at AGNESS2( 247 ft)
    Low: 57 at BLALOK(277 ft) & RUFUS(185 ft) & Celilo – East of(225 ft) & Arlie Mitchell R(1629 ft)

    High:34 at HOWARD Mt Howard(8150 ft)
    Low: 21 at KIRK (4519 ft )

    Largest Diurnal Change: 42 degrees
    KLAMATH NWR (65/23 ) (4531 ft )

    Heaviest Rainfall:
    2.03″ at BLACK MTN RIDGE(4965ft)
    1.70″ at HIGH RIDGE(4920ft)
    1.70″ at MILK SHAKES(5580ft)
    1.41″ at CW2313 Tollgate(5075ft)
    1.36″ at EW4395 Milton Fr(3454ft)
    1.30″ at LUCKY STRIKE(4970ft)
    1.25″ at LAGRANDE 1(3079ft)
    1.15″ at EW3836 Weston(3504ft)
    1.10″ at EMIGRANT SPRINGS(3800ft)
    1.10″ at MOSS SPRINGS(5760ft)
    1.04″ at Meacham(3724ft)
    1.02″ at PILOT ROCK 11E R(1919ft)

  7. Sapo says:

    I’m really hoping for a big rain in the next week or two. Need the salmon to enter the rivers lol!

    However, it’s looking pretty dry..

  8. tomnepdx says:

    Looks like the TV mets missed the ball on today’s forecast. There are some pretty moderate showers out there this afternoon when most expected today to be dry. I’m lovin it though. We need the rain!

  9. Paul D says:

    Absolutely loving this weather! It is so comfortable. This is the time of year when the house stays at a nice temperature and I don’t have to run the heat or A/C. The grass looks like it isn’t fighting for its life and I haven’t run the sprinklers for a week. Ten below normal is making up for all those 90+ days we had. We only need about 23 more and we’ll be even 🙂

  10. David B. says:

    45 degrees this morning, which was the overnight low.

  11. Jason Hougak says:

    Radar showing ample rainfall circulating around Spokane, Washington.

  12. schmit44 says:

    9/4/2015 Oregon (All) Temperature Summary

    High:77 at Rye Valley(I-84(2229 ft) & ALKALI FLAT(2495 ft)
    Low: 55 at BLALOK(277 ft) & WYETH(102 ft) & John Day River B(305 ft) & Port Orford(0 ft)

    High:37 at Rim(7050 ft)
    Low: 15 at CROW FLAT (5172 ft )

    Largest Diurnal Change: 38 degrees
    KLAMATH NWR (58/20 ) (4531 ft )

    Heaviest Rainfall:
    0.95″ at DEE FLAT(1260ft)
    0.63″ at CW9027 Ukiah(3415ft)
    0.60″ at PEBBLE(3450ft)
    0.58″ at SUGARLOAF(4328ft)

  13. David B. says:

    62 for a high here today. Took a hike with a friend and it really felt like autumn.

  14. Jason Hougak says:

    Ahhh, first fire of the season. Balmy 49F.

  15. Dave in SW PDX (235') says:

    It’s currently snowing at Crater Lake NP:

    • Jason Hougak says:

      That’s great, too bad we can’t start building out snowpack now.

    • Dave in SW PDX (235') says:

      It will be gone soon, but it’s a start. Seems like the switch has already flipped from “Summer” to “Fall”. Only 64° for my high today.

  16. pappoose in scappoose says:

    They’re out there!

  17. Jeff says:

    I think you’re being too hard on yourself, since even most of your “incorrect” forecasts were within 4 degrees of the actual values. For many years, weather forecasts predicted high and low temperatures within a 6-degree range in multiples of 5 (e.g., 65-70, or 70-75). Then, they started using an absolute 5-degree range (68-72, or 72-76). Now, most weather forecasters are predicting a specific value. It’s amazing to me that the specific temperature is predicted correctly with any regularity, given the number of potential variables on any given day. Just another example of how far the forecasting science has come in a relatively short time.

  18. lilfoot123 says:

    At Seaside this morning 55-60 already gorgeous

  19. Paul D says:

    My house is down to 67 inside this morning. That’s the coolest it’s been in waaayy too long!! Very nice!!

  20. Boring Oregon says:

    It’s so cold that my thermometer is telling me it’s —°

  21. Dave in SW PDX (235') says:

    Fog & 46°F – a very Fall-like Summer morning.

  22. 46F minimum this morning despite mostly cloudy skies. If this cool weather keeps up, I could be seeing frost by the end of the month!

  23. schmit44 says:

    9/3/2015 Oregon (All) Temperature Summary

    High:75 at DW5789 Eagle Poi(1463 ft) & EW1735 Central P(1285 ft) & MERLIN SEED ORCH(1144 ft) & UMATILLA(270 ft) & Medford, Rogue V(1329 ft)
    Low: 58 at LAKE OWHEE AND O(2400 ft)

    High:39 at HOWARD Mt Howard(8150 ft)
    Low: 22 at KIRK (4519 ft ) & IRAWS 40 (PUMICE (5956 ft )

    Largest Diurnal Change: 41 degrees
    KLAMATH NWR (64/23 ) (4531 ft )

    Heaviest Rainfall:
    0.43″ at SCOGGINS CREEK B(242ft)
    0.43″ at K7ZQU-7 Santiam(4790ft)
    0.42″ at CW7508 Enterpris(3848ft)
    0.40″ at TIPTON(5150ft)
    0.34″ at KB7DZR Joseph(3984ft)

  24. To be fair that warm blob played havoc with forecasting for everyone not just yourself. This was especially the case with the extent of any marine pushes, intrusion of low clouds, and forecast high temp. I noticed even during the “cool” days high temps ended up being almost always 2-6F warmer.

  25. 55F at 5pm this afternoon. Boy, it sure feels cool after all the heat we’ve been having. If skies clear tonight, I could be seeing a record low temperature overnight.

  26. schmit44 says:

    This mornings low of 50 at PDX doesn’t seem all that cold but the last time they had a morning low this cold was May 17th when they hit 47. What an amazing and unprecedented stretch of warmth we just had.

    • Here’s a bit of a perspective on the dry spell I’d like to share: I realize in Portland and other areas south of my location the stats were even drier than me. But here goes; I counted 113 days from when this drought pattern began for me (May 6) til when it ended(August 27). I added up the total precipitation during that period (1.92 inches) then checked what it would be proportionately over a 365 day period. (in other words, a year). The result? Just over 6 inches. Wow! A lot of trees and plants would be wiped out here if that happened.

  27. WEATHERDAN says:

    with a low of 50 Salem set a new record this morning. 73 consecutive nights with a low of at least 50. The previous record was 72 in 2014. 65 at noon on our way to about 71. That would put us at 92 consecutive days of at least 70. The record is 98 set in 2014. So 65 and mostly sunny. Last week the 16 day GFS meteogram had PDX at 3.36 inches of rain. EUG at 2.69 inches. SLE has had just .64. So once again as it has all Summer our prediction of lots of rain didn’t verify. On July 25th, August 10th, and this past weekend the total amount of rain predicted was over five inches. What we got was .65. Now the models are showing above normal temps and no rain until about the 19th. Even then most of the rain seems to be north of PDX. We shall see. Peace.

  28. W7ENK says:

    Overnight temperature dropped down 46.2 at my place. I wasn’t prepared for that, especially on my ride in to work. It was downright chilly when I left the house, and even after riding 8-1/2 miles, I barely broke a sweat!

    As for the warm weather weenies in Stevenson…. lolololololol

    • Mark Nelsen says:

      It’s all in fun. Actually “he-who-can’t-be-named” keeps me honest too. Nothing like a little trollin’ every 6 months…

    • gidrons says:

      He’s still sore about being suspended.

    • gidrons says:

      Jessie seems upset
      “Any issue I have ever had with Mark’s forecasting involves the fact that, when in doubt, Mark invariably shows the warmest case scenario in his 7-day forecasts, especially the latter half. Of course this is modified once he is forecasting for “tomorrow”, but whenever there is any disagreement in the 4-7 day range, he will almost ALWAYS reflect the warmer runs on the back half of his 7-day. This is fact, and it makes sense considering Mark blatantly states that he does not like cool, rainy weather and heavily favors warm and dry.

      Anyhow, just clarifying. My issue was never with Mark’s short term forecasting abilities. Only that his 7 days tend to skew warm when there is any doubt. It’s kind of amusing to see this all being brought up now considering I haven’t been a regular contributor to the Fox 12 circus blog for a couple years, but I guess what I think of Mark REALLY matters to him”

    • Mark Nelsen says:

      Again, I had spare time so I thought it would be fun to see exactly how the summer went forecast-wise. I had a feeling I was too cool most of the time (like everyone else). He has a good sense of humor too; I know he loves some good snarkiness. Plus, now I’m thinking I should do a winter version of this and include the entire 7 Day forecast. That said, I don’t have as much free time in the winter.

    • The reverse of that would be Jesse selling a cold biased 7 day in winter.

    • High Desert Mat says:

      I don’t know. Mark seems to have the first snowflake on 7 day forecasts before anyone else all the while with the coolest temps in winter. He usually doesn’t discount the gorge effect as quickly as others do.

    • W7ENK says:

      You must have a really fragile ego, Mark…

      …says the long haired, hippie punk, wannabe teacher reading tutor who’s whining about being poked at by a professional meteorologist. I mean, he even had a file, Mark. A FILE!!

      Thanks for the link, gidrons. That’s some good reading, right there… lol 😆

    • Boydo3 N. Albany says:

      “He Who Can’t Be Named”..hahaha

    • Jesse-Stevenson says:

      I’m glad you know it is all in fun Mark, mostly… 😉

      I definitely have a good sense of humor about it. People love seeing a good “rivarly”.

      Here’s to the best forecaster in Portland (I’ve never denied that), and keeping him honest. 😉

    • Dringus says:

      W7 – what exactly does someone’s appearance/career have to do with this? Drop the personal stuff. I’m sure I could investigate your life and point out a bunch of your shortcomings career/appearance wise. You might not like Jesse but he certainly demonstrated more weather knowledge and passion than the hordes of casuals around here.

      Mark gets it – dude is just snarky and some of us found it kinda funny.

      Ah well.

    • Dave in SW PDX (235') says:

      Dringus – No offense, but you should ease up on W7. If you had clicked through and read his link you’d understand that he was using Jesse’s own self-deprecating words. I don’t think W7 intended to be mean-spirited in this case.

    • Dringus says:

      Damn dave you’re right! Thanks for the insight there. Jumped the gun.

    • W7ENK says:


      So quick to judge…

      Thanks Dave, I’m glad someone was paying attention.

  29. Kyle says:

    Before the Pacific Blob screwed up forecasting Mark usually did have a warm biased because he would be really excited during really warm episodes.

    Now with the warm pacific blob nobody can really have any biases because no matter what they will likely forecast too cool no matter how warm their bias shows.

  30. Paul D says:

    It’s not a cold bias, it’s wishful thinking! 🙂

    • PurpleHaze says:

      It’s all about the attitude of the forecaster. If the forecaster is really enthusiastic about unusually hot weather for the climate then it will most likely show in the forecast either thru direct forecasting or attitude wise.

      Nothing wrong with that but it does get annoying when it’s all one sided.

      I know plenty of weather posters that go overboard however when cold weather comes so I guess it balances it out in the end.

      Whatever Mark’s bias shows up there will be a balance of the opposite side that shows too.

    • Mark Nelsen says:

      Excellent point. I should do December-February too and see how that turns out

  31. Yesterday morning my minimum temperature was 47F. Hadn’t seen a reading that low in the first week of September since 2002.

  32. StormyClimate says:

    No… Mark

    Your not the only one who has either a hot or cold bias all the time. Most if not all the time you are the one who makes more sense than anyone when it comes to local weather down there in PDXland.

    Aside from all that…

    Pretty wet (downright sopping) here the last 6 days

    0.04 on the 28th
    0.94 on the 29th
    0.93 on the 30th
    Trace on the 31st
    0.33 on the 1st
    0.08 on the 2nd

    ^ The wettest 6 days together I have had all year.

    This summer 9 days in the 90’s. I usually expect maybe 3 or 4 each summer here and I would consider anything above 4 to be an exceptional summer for 90 degree temperatures. I did have 44 days of 80 and above temperatures. Only 7 days had a high of below 70 degrees.

    My rainfall for August ended up being 2.33 inches. Normal over 8 years of measurement here is 1.34 inches.

    • PurpleHaze says:

      Most of those who are biased either for warm or *cold tend to be more Seattle Centric when it actually comes to forecasting.

      That area gets something called the Pacific Convergence Zone or PCZ I think it’s pronounced which creates local effects where Seattle proper misses out on.

    • David B. says:

      Puget Sound Convergence Zone (PSCZ). But that affects precipitation patterns more than temperature.

    • StormyClimate says:

      The PSCZ hardly ever affects to Tacoma. That usually affects areas like Snohomish, Skagit, and Whatcom counties. Maybe a few times Northern King and Kitsap counties along with Island County in the San Juan Islands. I live in Pierce County and our weather is more like Olympia than Seattle.

      More often then not I get more rain than Seatac even because there is less shadowing from the Olympic Mountains here. Precipitation that makes it through the Chehalis Gap affects me more that the PSCZ though.

      On a rare occasion (as has happened in the past) the PSCZ visits Tacoma even in the winter and I have actually watched it drop as much as 3 inches of snow here in my area. The air gets a little enhanced when it moves straight down the main ship channel of Puget Sound with moisture all the way to Commencement Bay next to Tacoma and then gets lifted when it encounters the hills just south of the bay in the area where I am at. Much of Tacoma lays at over 200 feet above sea level in town. Here where I live it is 453 feet and I thus get more snow than anywhere in Tacoma usually. I definitely get a lot more often than the valley floor down in Puyallup much of the time.

      My all time record for snowfall in one nice big storm is 16 inches in December of 1974 here. My step dad and I measured it that day when he couldn’t make it into work that morning.

  33. brian says:

    A cool 47 degrees here and a balmy 59 at pdx, geez talk about a crazy heat island effect, yuk.

  34. schmit44 says:

    9/2/2015 Oregon (All) Temperature Summary

    High:88 at LAKE OWHEE AND O(2400 ft)
    Low: 66 at LAKE OWHEE AND O(2400 ft)

    High:44 at Rim(7050 ft)
    Low: 34 at MAZAMA (4596 ft )

    Largest Diurnal Change: 37 degrees
    Lorella (76/39 ) (4160 ft )

    Heaviest Rainfall:
    0.96″ at LOG CREEK(2800ft)

  35. hahaha. This post made my night. Especially when you specifically named Stevenson and Tigard.

  36. Tyler Mode in Battle Ground says:

    I know someone that lived in Orchards, and now lives in Stevenson!

    Beautiful area too!

    Nice to see you aren’t too warm biased as others have said in the past.

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