Independence Day Weekend Outlook

June 30, 2016

Planning to go camping at the Coast or in the Cascades this weekend?  I’ve got your forecast covered.  Same thing if you plan to head east of the Cascades.


  • In general this 4th of July Weekend will be mild to slightly coolish (mainly Sunday) around the Pacific Northwest.
  • Who is guaranteed dry weather?  Anywhere south of Portland west of the Cascades and anywhere east of the Cascade crest & eastern Gorge.
  • Who MIGHT see a shower?  North Coast, mainly on Sunday AM.  Same thing from the metro area north into SW Washington…again on Sunday AM only.
  • Afternoon temperatures: 60s at Coast, 70s in valleys, and 80s east of the Cascades
  • Varying coverage of morning/midday clouds will continue west of the Cascades
  • Expect mainly sunny skies all 3 days anywhere east of the Cascade crest.  That also includes the Columbia River Gorge east of Bonneville Dam.

Here are the graphics showing a few more details for each area:




This pattern will continue through the entire week ahead.  High temperatures will remain at/below 80 degrees west of the Cascades.

Chief Meteorologist Mark Nelsen



A 12 Day Outlook: Is That Ridiculous?

June 27, 2016

Yesterday I first used this graphic during the 10pm show; of course this is today’s version:


It’s a 12 day OUTLOOK (not a detailed forecast).  It contains an abbreviated 7 Day forecast, then a more general outlook for the following 5 days.  I’ll use this in the 2nd half of the 10pm show and sometimes in other shows as well.  There may be some days in which I don’t use it at all, you can see the reasoning below.

In Portland all long-range TV forecasts were just 5 days until around 1996.  That year a new news director showed up at KOIN (I was there from 1993-2000) and suggested we do a 6 Day Forecast.  How clever…it was Channel 6!  Forecast accuracy was gradually improving in the models so the extension seemed reasonable and we implemented that change.  Within the next 5 years the other 3 stations went to 7 day forecasts and we did at KOIN as well.  When I came over here to Meredith Corp. as KPDX Chief Meteorologist in 2000, management was listening to some weird consultant that only wanted a 4 day forecast (what????).  I compromised and we went back to a 5 day forecast for two years.  When KPTV/KPDX merged in 2002 (new bosses!) the KPDX newscasts ended and I was back in the 7 Day forecast game via KPTV from there on out.

I know of at just two other times longer range forecasts have been used on-air here in Portland.  Sometime in the late 1980s I remember Miles Muzio at KOIN doing “The Long Ranger”; a 14 day forecast.  Wow, that was pretty bad considering the state of forecasting in the 1980s.  Yet, I clearly remember getting all wound up when he showed freezing rain possible 12-14 days away!  It didn’t happen of course.  Then here at KPTV around 2009 on Good Day Oregon our meteorologist Drew Jackson would occasionally do a 12 day forecast.  He did that when the pattern appeared stable enough or clear enough that far out to give some confidence.  That was my inspiration to bring it back.

So why bring it back?

I think it’s time for several reasons:

  1. Numerical Forecast Modeling (THE MODELS) is gradually getting better and better, and more important…
  2. …Model Ensemble forecasts are now available to us here at FOX12.  Those are collections of many different runs of each model.  When they are all similar, confidence goes up.  When very different? Low confidence!
  3. We are all seeing 10-14 day forecasts all over the place now on apps.  Even our own FOX12 Weather App goes out to 10 days!  That’s all computer driven of course; no human interaction with that forecast.  Those numbers come straight from long range models, regardless of the accuracy.  Since all that information is out there, at least I can give you some perspective on what you’re seeing.  That’s where the 12 day forecast helps out a bit.  For example, if just one model is showing snow in 9 days and your app says so, I can throw a little reality into that forecast based on what others are showing.
  4. People ask me all the time about the “big picture” beyond the 7 Day Forecast.  Examples:  Do you see a dry period coming up to stain my deck? Any chance at all for extreme heat in the next 2 weeks? Are we clear of a “snow threat” for the next 12 days?  Those questions will often be answered by a 12 day outlook.

There will be times when long range models are all over the place; I likely won’t even bother to guess on those days.

So is a 12 day forecast RIDICULOUS in 2016?  In this format I sure don’t think so!

By the way, the big thing I’m noticing in maps for the first 10-14 days of July is a total lack of extreme heat.  This summer is sure looking different than last year…a good thing.  Take a look at the 16 day temperature anomaly from the 12z GEFS ensembles:


Below normal for this coming weekend then 10 degrees or less of above normal temps through the 13th.  That means highs would be somewhere between 70-88 over the next 2 weeks.  The monthly ECMWF run came out this afternoon…very interesting.  About as normal as it gets.  Check out four weeks of surface temperature anomaly across N. America.  Near or slightly above normal through July:

Chief Meteorologist Mark Nelsen

Wettest Day in a Month!

June 23, 2016

11pm Thursday…

Wow, some real downpours out there this evening.  Yes, it has been noted as a forecast failure on the report card for next week too…I’m sure you were wondering!

Take a look at the rain totals for the metro area.


The PDX number is incorrect since it appears we’ve seen .53″ so far today; the wettest day since May 15th.  In Troutdale it has been the wettest day since December!

The timing of the heavy rain is excellent since we’re about to head into a very dry pattern.  Take a look at the GFS 10 day outlook…other than showers tomorrow it appears dry through at least the 3rd of July:


Also notice the last 3 days of this model have shown no rain next week:


The ECMWF ensembles from the 12z run today were similarly dry…showing no rain through at least the 5th of July.


The total at the bottom is the ensemble average.  Each line above is one ensemble member.

The key message here is that summer is going to arrive BEFORE the 4th of July this year.  Or maybe it arrived in early April, or May, or early June…you choose.  Lots of warm spells this spring!

The good news is that I don’t see HOT weather on the way, just warm to very warm weather.  It’s unlikely we get to 90 or above over the next week.  That’s because we don’t get a hot ridge over the West Coast but it remains to our east, allowing incursions of marine air from time to time.  Nature’s air conditioning will keep things under control west of the Cascades.

Chief Meteorologist Mark Nelsen

Balloon and Camera Launch

June 23, 2016

Brian Torres (a teacher at Springville K-8 in Beaverton SD) sent me a great video showing a balloon their school launched a couple weeks ago.  The students and staff put the whole project together; a great success too!


They attached a camera and it made it to 102,000′ before crashing back to earth in the Gifford Pinchot NF somewhere north of Carson, WA.

Notice the nice ice halos way up in the cold air partway through the video…enjoy!

Chief Meteorologist Mark Nelsen

Trip Update Saturday PM

June 18, 2016

Odometer says 2,210 miles so far and we are driving across northern Arizona on our way to Page today.  Vacation trip has gone well, at least the first 10/11 days.  I’ve been posting pics and comments on my Mark Nelsen Facebook page.  Limited internet and/or time too.  Mainly sunny and warm to hit each day   Here are a few pics: image image image image image image

Vacation Time: The Nelsen’s Epic Southwest Trip

June 8, 2016

There are so many neat places to visit in our great country…too many to visit in a lifetime.  But over the next two weeks I’ll be joining my wife and two kids on a 3,000 mile road trip through parts of the Desert Southwest to see some of those sights.   It’ll take about 13 days and we’ll tour 4-5 national parks.  That includes:  Arches, Canyonlands, Great Sand Dunes, & Mesa Verde.  Possibly Zion briefly as well.  I’ve always wanted to see the cliff dwellings in Mesa Verde and all the neat landforms in Arches/Canyonlands.  We’ve been to Great Sand Dunes in the past…in fact that was the last long trip in June 2012.  Read about that one at the link.  We’ll also get some pics at the Four Corners monument and drive through Monument Valley Utah and tour a slot canyon.

Here’s the route, heading southeast to Utah first.  Can you drive from Portland to Moab UT in one day?  I’ll let you know how it goes…



We’ll be traveling in a 4Runner towing a pop-up trailer…relatively spartan accommodations I think.  We’ll stay in 8 different campgrounds…it’s all been planned out.

Most likely no blog postings during this time, unless for some reason I have tons of time to post pics.  I’ll be back at work on Wednesday the 22nd.

100 Degrees, Warmest June Day in 8 Years!

June 5, 2016

Sunday 10pm…

PDX hit 100 degrees today, the 2nd earliest we’ve ever hit that number:


We of course broke the daily record, so did Hillsboro, Vancouver, & Troutdale.  As mentioned in the previous posting, we’ve only gone above 98 degrees once before the 3rd week of June.  As a result, today’s 100 degree reading is the 2nd earliest on record here.


Now if you’re worried this is a sign of the summer to come, don’t panic!  I’ve got two thoughts on that.  First, in just 11 of the past 20 summers we’ve hit 100 here in Portland.  So I’d give it a 50/50 chance that we hit it again; it’s possible you just lived through the warmest day of 2016!  Maybe, we hope…

This caps off a historic first weekend of June weatherwise.  4 records at PDX; two highs and two record warm lows.


Where do we go from here?  We are definitely getting a shallow marine push with cooler air surging into at least the westside of the Willamette Valley.  That will spread out and along with a slightly cooler atmosphere overhead means high temperatures should be right around 90 degrees Monday in the metro area.  A little more cooling is likely Tuesday, but high temps still remain well into the 80s.

Beginning Wednesday things go back to normal with more cloud cover and temperatures well down into the 70s.

Hate the hot weather?  There is good news for you.  All models are in great agreement that we are headed into a cooler than normal pattern starting late this week with showers at times.  Check out the GFS model ensemble temperatures for the next two weeks.


Ensemble means many different versions of the same model, so confidence is pretty high with this.  It appears much of the rest of June may not look at all like this first week.  The ECMWF model is almost exactly the same.  Two more very warm days and then normal to maybe a little below normal.

For the Junior Parade Wednesday afternoon, at this point it appears dry.  Comfortable temperatures too!


Chief Meteorologist Mark Nelsen