Last Night’s Storm; An Analysis

January 18, 2012

A strange thing happened today…my coworkers kept saying “good job!”, or “you guys really nailed that storm!”.

Hmmm, now I’ve mentioned in the past that I feel I get a bit to emotionally wrapped up into these events, and this time I felt like in the end I really missed it.  So why the disparity between how I felt I did and what others thought?

1. In my mind, and alluded to in this blog yesterday, I really thought we’d only get very brief light accumulations for the bulk of the metro area.  Of course I had 1-3″ in the forecast during the 6pm show yesterday (so did Steph).  So technically the actual forecast (that 50,000 tv viewers and online viewers at that time saw) was far more than I really thought we would get.  A large part of the metro area DID get a total in that range.  I updated the totals up above.  At least all of the west metro, south, and much of inner east/southeast metro.  And it did not snow south of Wilsonville which was a perfect forecast for all of you in Salem/Woodburn etc…

2. This is the main point:   I, and probably many of you, focused on “how much snow was coming”.  That’s what weather geeks do.  And if it was a snowstorm that was coming for the day (to play in) most other people do as well.  Apparently most of our viewers, and just about everyone I work with seemed to focus on “snow overnight, then a quick warmup with no major issues for the morning commute“.  That’s exactly what happened, most areas transitioned to rain quickly after 1-2am, and the heavy rain melted enough of the snow to avoid a mess.  I didn’t realize that many of my co-workers were thinking we might be totally wrong and it would be 30 degrees and heavy snow at 8am. 

So what went right?  The Winners:

  1. Timing in general, it happened a little faster than I expected, rain to snow, then back to rain.  But models did very well.
  2. Mesoscale models clearly showed a changeover to snow as a distinct possibility, they are getting better and better!
  3. Heaviest totals to the north and west of the metro area.  Lots of 12-15″ totals above Scappoose, Vernonia, Amboy etc…
  4. No snow south of southern metro area.  1/2″ at Sherwood is the farthest south I saw.  None in Wilsonville/Canby.
  5. Quick warmup with south wind today.  I remember seeing a comment on here a day or two ago thinking that 50 was way too warm of a forecast for today.  It hit at least 53 at PDX.
  6. Positioning of the surface low…great job most models!  Came inland between Astoria and Hoquiam.  The NAM was a little far south, and several days out the GFS/ECMWF/GEM were better than the much farther south NAM.
  7. Heavy snow (10″+) in the right places as mentioned before, plus the 12-18″ in the Hood River Valley was a nice verification to see.
  8. This blog…no drama or major issues as we’ve often see in the past.

What went wrong?

  1. More snow than expected eastern metro and Clark County.  3-5″ east of I-205 was more than expected.  I didn’t expect the 3-5″ totals in east Vancouver, Camas, and Hazel Dell areas.  As mentioned earlier though, maybe much of the public didn’t care since it was late at night and melting quickly by daybreak.
  2. Me saying “my gut feeling is we get very little snow” on the evening broadcast.  Should have just kept my mouth closed and the forecast would have basically been okay.

So I’d rank it a 30% bust, but 70% fine forecast.  Feel free to disagree in the comments, you know I’m not easily offended.

By the way, has anyone noticed the very cold arctic air creeping farther south than any model shows into north central and northeast Oregon this evening???  More on that and how it affects the Gorge forecast on a post later this evening.

Chief Meteorologist Mark Nelsen


Wednesday Morning Storm Update

January 18, 2012

It’s the day after the storm, or for some of you the storm is still ongoing…

If you’re just checking in for a forecast, it’s straightforward for the metro area: Showers and windy the rest of today, south wind gusts should stay below 40 mph.  A balmy high between 45 and 50 degrees.

 Here are some highlights of the storm so far:

– Heavier snowfall than expected of course here in the metro area.  Looks like widespread 1-5″ totals.

– It DID change to rain around 1-3 am, so at least that part of the forecast turned out okay.

-It DID snow heaviest out against the Coast Range…I just got one report of 11″ on the west side of Forest Grove.

-The low pressure center is just north of Astoria right now, moving onshore.  Models did really well with that, especially the WRF-GFS.  NAM was slightly too far south in the end.

-South wind is picking up across the metro area right now and it’ll be quite windy through the afternoon, pushing temps up around 50 degrees.

– Check out those coastal gusts!  109-110 mph at spots on the central coast, lots of 80+ reports.

– Mountain snow:  Mt. Hood Meadows has received 37″ since 5am yesterday…must be close to it’s all time record.  I think that’s somewhere in the 30s for a 24 hour total.

Another surface low moves in to our south tomorrow morning.  This pulls fresh cold air into the eastern Gorge.  If so, you folks in the central/eastern Gorge could have another foot on the way.  It might be a significant ice storm at the western end towards tomorrow morning too as the east wind gets going (not in metro area).

What did go wrong?  I should have trusted those mesoscale models better.  They clearly showed a snow profile.

I had the worst drive ever on the way home last night.  Extremely heavy snowfall from Beaverton down Hwy. 26 onto 405…real slow.  Then the Marquam Bridge was just closed as I approached.  On SB 405 that forces you onto SB 5.  Did you know there’s no exit for about 2 miles until you get way up to the Terwilliger exit?  So I drove down the hill from there onto OR 43, across a still and snowy Sellwood Bridge, through an empty Sellwood, then through Milwaukie (it actually snow there last night), a very slow drive all the way to I205 & 224 entrance ramp.  Meanwhile, here and there were vehicles stuck in the deep slush/snow.  Up I205 to 84.  Slow drive in blinding snow to Corbett exit.  Halfway up Corbett hill a guy is sitting in the middle with flashers on.  I ask if he needs help “no, I’m just from Portland and checking out my 4 wheel drive in the woods”.  Hmmm, okay, move on.  I get within a mile of home in the middle of nowhere, dodging trees hanging way down over the road.  Come around a corner and Bam!…a large tree fallen across the road.  I back up, park, start walking.  All you can hear is occasional cracking from limbs and trees falling.  Just as I start, a Reliance Connects phone company crew drives down looking for a way to get to their equipment.  They have a chainsaw!  So at 1:30am, in a suit and boots, I’m helping remove a tree off the road, which is somewhere 8″ or so down.  What  a weird experience .  I got home and to bed around 2:30am.

Chief Meteorologist Mark Nelsen 


Snow Total Tuesday Night

January 18, 2012

 Keep discussing weather on previous posts.

1. Fresh snow received between 5pm & this morning

2. Total (for those of you in the hills that have a lot more)

3. Location

4.  Elevation if you are up close to 1,000′ or higher.

And don’t forget, the first time you post a comment, or use a different IP address, your comment is held for moderation.  After that you can post anytime.  It may be a couple hours until I get to your comment.  This keeps the “spam issues” away.

This is what we have so far. Sometimes two or more of you reported from the same location; I had to choose one of those, don’t hate on me if I didn’t use yours!

NW OF METRO AREA:
8″ Castle Rock
5″ Longview
12″ Columbia City
12″ Vernonia
10″ Scappoose

CLARK COUNTY
3″ Woodland
5″ Battle Ground
12″ Amboy
16″ Yacolt
6″ Hockinson
4″ Hazel Dell
2″ Vancouver
3″ E. Vancouver
4.5″ Camas

WEST SIDE METRO AREA
8-11″ Forest Grove
3″ Cornelius
2″ Hillsboro
2″ Beaverton
4″ Cooper Mtn
0.5″ Sherwood
1.5″ SW Portland
4″ West Hills

CENTRAL AND EAST METRO AREA:
2.2″ Official Portland Total at NWS
5″ St. Johns
2.5″ N Portland
2.5″ SE Portland
3.5″ E Portland
2.5″ Clackamas
4″ Happy Valley
4″ Sellwood
2″ Milwaukie
2″ Oregon City
5″ Gresham
4″ Fairview
4″ Troutdale
7″ Corbett
12″ Sandy

None in or south of Wilsonville/Canby areas.