A Taste of Fall This Morning

August 21, 2014

10pm Thursday…

Quite a chill in the air this morning, lots of 40s around the metro area.  PLOT_Lows_Metro For some of us it was the coldest in about 2 months.  At PDX the low of 54 was the coolest since July 25th when we also hit 54 degrees.  MarkTemp_Last12Days_LowsPDX That broke the long string of mainly 60+ nights we’ve been seeing since late July too.  Between that and what I see on the maps ahead, it’s pretty obvious we’ve passed the “peak of summer”.  Sure, there will be plenty of warm days (80-90 degrees) in the next month, but the long strings of hot weather are history for this year.  It probably doesn’t help that some kids go back to school in just 4 days, the rest in less than 2 weeks.

I didn’t post over the past week because the weather was slow the end of last week and over the weekend, plus my family and I did our last camping of summer at Diamond Lake (near Crater Lake).  No more vacation time in the next month, in fact I’m probably going to earn a bunch of days since Brian is about to go on paternity leave and we’re short a weather person.  But that’s how the business goes, you work long hours and many consecutive days at times.

Here are a couple of pics from the area.  I’m no photographer, and it was real hazy.  My son and I hiked up Mt. Bailey above the lake…a tough climb but not technical by any means.  The last picture was a little “window” through the ridge of rock at the top of the mountain.  That was real interesting; hate to fall out that one!




Chief Meteorologist Mark Nelsen

A Slow Thursday

August 14, 2014

It’s been a real slow two days weatherwise…especially considering an upper-level low has been overhead.  Three days of at least partially busted forecasts plus lots of time spent creating some graphics has meant no blog posts.

Very little going on this evening except some flooding in…of all places Hermiston.  Showers and thunderstorms kept developing over the Boardman/Hermiston area for a couple (or three) hours.


Quite an unusual occurrence in one of the driest places in the state.

I’m a bit late, but I see the NCDC climate data is out for July. july_usa_temps 

No big surprise, the West was hot and the East was “cool”.  Of course cool in the east is still warmer than what we typically see.  The 119 in Oregon means that out of 120 Julys, this was the 119th warmest…2nd warmest on record here!  

Is summer getting warmer here?  It appears that at least the June-July part is west of the Cascades:


That is a plot of July temperatures for Oregon Climate Zone #2, which is the Willamette Valley zone.  There is a slight uptick the past 30 years or so.  Those chilly summers around 2010 sure stick out though!

Chief Meteorologist Mark Nelsen

A Busy Weather Day Ahead…In August

August 12, 2014

Here in Portland July through mid October is the deadest time of the year weatherwise, with September generally being the peak of the boring weather season.  That’s because we rarely get thunderstorms west of the Cascades.  But today is one of those rare times in which we could see some real action.

The reason is that we have a rare combination of lots of moisture all through the atmosphere, including here at the surface.  Plus a very warm atmosphere overhead.  The upper-level flow is southeasterly over us, which is bringing in more moisture from the southeast.  The atmosphere is unstable, which means parcels of air want to suddenly rise through the atmosphere and form those huge thunderheads.  And the final trigger for today is the upper-level low that was off the California coastline is lifting north through the state of Oregon this afternoon.  Those factors have all combined to put anywhere in Oregon over and east of the Cascades in the SLIGHT RISK category for severe thunderstorms.  The primary danger will be damaging outflow winds and hail.

But even west of the Cascades we’ve seen the action early.  Take a look at the hundreds of lightning strikes right after sunrise in the north Oregon Coast Range and Willapa Hills!  lightning_tue Those were all strikes in a 30 minute period!  I see that one RAWS station in the Coast Range had almost an inch of rain in a very short period of time.  With such a warm and humid airmass it can rain like it does on the Gulf Coast…buckets at a time.

Here is the latest lightning  image for western Oregon as of 10:00am:


A bit quieter, but I think we’ll really see the action pick up this afternoon and evening.  At least the cloud cover will keep temperatures much cooler than yesterday.  Although it’s a humid day, high temps will stay well below 90 degrees.

To recap…

  • ANYONE could see a thunderstorm today
  • Everyone will not see one though
  • Any storm could include very heavy rain briefly
  • Gusty winds are possible within a few miles of thunderstorms, that’s because air rushes out of the bottom of storms and spreads out below
  • East of the Cascades the risk for damaging wind and large damaging hail exists

Tomorrow we’ll see our coolest day in quite awhile, highs only around 70 and showers/clouds.  More of a gloomy May (or late September) day.

Chief Meteorologist Mark Nelsen




99 in Portland Monday, Ties for Hottest of Summer

August 11, 2014

5pm Monday…

What a scorcher, widespread highs quite close to 100 degrees today…here are the official high temps at 5pm.



Other than a cell trying to develop over the SE side of the metro area and one over Government Camp, no thunderstorms within 100 miles of the metro area at 5:15pm…

Chief Meteorologist Mark Nelsen

100 Degrees in SW Washington Today

August 11, 2014

4pm Monday…


So far we’ve hit 93 here in Portland, 97 in Hillsboro, but no official stations have hit 100 degrees west of the Cascades…except to our north!


Kelso, Castle Rock, Chehalis, & Centralia have all breached the triple digit mark.  They didn’t get the high clouds we saw early-mid afternoon down here in the metro area.  Off the map is The Dalles at 106 degrees this hour.

Will we get thunderstorms this evening?  Tough call, it’s quite possible but by no means a slam dunk.  Models are still quite insistent on keeping just about all the action on the far east side of the Willamette Valley and then over/east of the Cascades.  But anyone (including at the coast) could see thunder between now and Tuesday morning.

I CAN guarantee another unusually warm night.  The 69 last night was the warmest low temp we’ve seen in several years.

Stay tuned…

Vacation Wrap Up

August 9, 2014

I (may or may not have) broken the law today when I unknowingly entered “The Forbidden Zone”.  Luckily no men in black suits showed up at my door; more on that in a minute…

I take most of my vacation time off in July and August for two reasons…it’s the SLOWEST weather time of the year, and it’s the BEST weather of the year in the Pacific Northwest if you like to enjoy the outdoors.  And with some of the best terrain in the entire USA, one would think that anyone who has moved here does enjoy the outdoors.  I like to camp, hike, and bicycle generally.  I know, not so exciting, but I’m a pretty laid back guy.  I just used up 9 vacation days the past two weeks, although I’m earning another back by working this evening.

Now when I come back from a vacation period in summer I often have coworkers ask me “what did you do?” or “where did you go?”  This time around I went on two brief camping trips and then rode my bike a bit at home.  I’m a bit of an adventurer and love the open roads and clear views.  It’s not that I don’t like people, but I just love being out in nature removed from civilization.  It’s possible I was born a century later than I should have been.  Hope that doesn’t make me a recluse; but if so that’s fine.

My family and I went camping at Big Lake and Olallie Lake (two nights each) about 10 days ago.  I had never been to Big Lake, which is just a couple of miles south of Santiam Pass, just below Hoodoo Ski Area.  We had a spectacular sunset one night, and I’m not photographer, but here you go.  Sunset on Mt. Washington:


There are a ton of OHV trails nearby, so on Monday my son and I rode them on mountain bikes since the ATVs were all back in their owners garages by then.  If you have a choice, always camp at Cascade campgrounds on the weekdays when it’s much quieter and slower.  I have also never been to Hoodoo Ski Area, so one day I biked/hiked to the top.  Quite a view!  It was a hazy day with high clouds, thus no blue sky.


Olallie Lake is probably my favorite place and it didn’t let me down!  It’s at 4,900′ on the Cascade crest an hour or so SE of Estacada.IMG_0454 The road has been dramatically improved (shhh!), enough so that driving a 1990s motorhome up there was no problem.  Mosquitos were just about gone too.  At most lakes in the mountains they disappear in August.  Here are a few pics of a hike .  One of the reasons I love Olallie is that the southern half of the lake forest was burned in a fire in 2001, so the view is totally open.  IMG_0453 The neighboring lake, Monon, is just a short walk away and you can have the lake to yourself for swimming.  This entire area is now covered in 5-10′ tall pine trees as the forest has begun growing again.


One morning I took a one hour hike down past Long Lake IMG_0451 and peeked down into Warm Springs Reservation’s Dark Lake;  IMG_0448  Pretty cool eh? In this area the fire burned just about everything.  That is Mt. Jefferson in the distance.

After a few days back at home, we headed out to visit family and friends in Cove.  There were thunderstorms nearby (last Saturday evening), and we had a solid 20-30 minutes of strong outflow wind…maybe gusts 30-40 mph.  You don’t get that westside very often!  Camping on this trip was at Philips Lake southwest of Baker City for two nights and Magone Lake for two nights.  A really nice campground (Union Creek); extremely rare to have electricity at a Forest Service campground.  I like this spot not just for being in Oregon’s “Thunderstorm Alley”, but also because the open pine forest has a bunch of mountain bike trails around the lake. IMG_0461

The reservoir was significantly lower than when we were there a few years ago.    I enjoyed going over the pass between there and Unity Reservoir to the south.  Lots of curves and no traffic; it would be perfect on a bicycle or motorcycle.  There’s a nice state park at Unity, but the water was extremely low and it’s just sitting out in the hot sagebrush.  We didn’t camp there.  Magone Lake is a new spot I’ve never camped at or visited.  It’s on a paved road about 15 miles north of John Day in the Blue Mountains.  What a neat place!  Only about 50 acres big, but a great campground with bike/hike trail around it.IMG_0464 It was formed in the 1800s by the Magone Slide, a landslide that dammed a creek.  There are trees sticking out of the water and very old trees on land that are bent because they “rode” down with the landslide. IMG_0465

The water in both lakes was real comfortable this time of year, so camping involved a lot of swimming too.  Once again, both of these campgrounds were dead quiet on weeknights.  The drive back to Portland on Tuesday was north on 395 through Long Creek, Ukiah, Heppner, then back to I-84.  I had never visited any of those places so it was good finally see what they look like at ground level.

This trip really cemented my feelings about where I might want to retire…anywhere east of the Cascades.  I really like the Grande Ronde and Baker Valleys, plus the greener parts of Central Oregon (Sisters).  I grew up here on the rain west side of the mountains, but I really want  more sunshine than the westside can provide; and I’m talking about year-around, not just in summer.  I just find I’m far more active when the sun is out.  Also, I really enjoyed having thunder and lightning “around” at times.  It just felt so much more like summer to me with those clouds billowing up some afternoons and seeing lightning from time to time at night.  We just don’t get that much west of the mountains.

About THE FORBIDDEN ZONE?  That was today.  I often bike up around the Larch Mountain area (east of Corbett) and today wanted to try a new loop.  You don’t have to go much farther south or east to find the edges of the Bull Run Watershed; Portland’s water supply.  I don’t think most people know about the vast area in eastern Multnomah County over to Hood River and northern parts of Clackamas County that the Bull Run Watershed encompasses.  The public is forbidden from entering this area…it’s off-limits to even hikers and has been for many decades.   On any logging road that crosses the boundary you will run into a sign like this:

photo 2

Pretty clear I think.  But today I took some even smaller roads (more like jeep tracks) and at one point came up on the back side of one of these gates…which made me wonder how I crossed the boundary.  I wasn’t too worried since the terrain looks like this photo 3 and I never saw another human in 90 minutes or so.  I think it’s highly unlikely that the water police will be after me.  And don’t worry, I didn’t leave anything in Portland’s water supply… (added 8/21).  I was contacted by the Portland Water Bureau folks after they read this blog post.  They sent a nice note pointing out what a treasure we have up there with the Bull Run Watershed.  They didn’t ask me to apologize, but I do feel a little badly about being so flippant about the great water resources we have here.  For the record, it appears on closer examination that I probably didn’t actually cross into the “zone” but the signs make it appear that way.  Here is part of what they asked me to add:  “…Unauthorized entry into the watershed presents a potential risk for the introduction of bacteria and other contaminants to the Bull Run source water. Legal protections and access restrictions are the primary safeguard against contamination, preserving the ecological functions of the watershed that contribute to safe drinking water…”  

Back at work tonight now and looking at the maps it looks HOT!  The next two days feature weak offshore flow, which pushes temps well into the 90s.  Of greater interest is the moist south-southeast upper-level flow which sends moisture for thunderstorms our way.  Tomorrow I think anywhere south of Salem could get an evening thunderstorm.  Than anyone could see thunder later Monday and early Tuesday.  After that we cool down.

Temperature forecast on Monday is tricky; weak offshore flow and 850mb temps around +24 mean we COULD hit 100 degrees if skies are sunny.  I think that’s unlikely so I went for a high of 98.

Chief Meteorologist Mark Nelsen




Hot Weather Ahead, Thunder Risk Again Too

August 8, 2014

Just a quick note to let you know I didn’t disappear on vacation.  I’m back for today and Saturday and then all of next week too.

First, remember that today is one of the 3 days in Portland’s history that we made it to our all time record high.  MarkHeatwaveStudio_1981 During a heat wave in 1981 we hit 107 TWICE!  That sandwiched a 105 degree day.  I’m not aware of any hotter 3 days in Portland’s historical record.

We don’t have temps that hot on the way, but the heat is definitely turning up Sunday and Monday.  We may get quite close to 100 degrees again for just the 2nd time this summer on Monday.  That’s because the onshore flow we’ve seen all week will switch to a light OFFSHORE wind Sunday and Monday.  At the same time upper-level ridging builds overhead pushing 850mb temperatures up to around +24 or +25 by Monday.  Those two combined have given us 100 degree temperatures in the past at this time of year.

A real wildcard Monday is cloud cover as an upper-level low to the south pushes moisture up over us.  Obviously this is a thunderstorm pattern too.  So expect warmer nights and humid weather for awhile starting Sunday night.

More tomorrow…

Chief Meteorologist Mark Nelsen


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