January 19, 2012

Major Freezing Rain/Snow Event

I drove to the UW this morning.  A big mistake, with a slush, packed ice, and snow along the way.  In north Seattle the freezing rain left a 1/4 inch crust on the snow...and now it is turning into snow as the precipitation intensity increases. (I understand the city is now sending out plows to take care of these roads)
Icy Window at Sea Tac: Picture Courtesy of Seattle PI
Well folks, this is not my profession's finest hour.    We had forecast the continuation of the light freezing drizzle of yesterday (an irritant, but not a major threat) and then a warm-up today with rain coming in late. Our models did not indicate that the precipitation would move so far north, so fast.

One thing I think is clear...thank god for the new coastal radar.  By 4:30 AM it showed that the forecast was going bad and moisture was streaming in farther north.  (below is the Langely radar at 5 AM)
My colleagues in the NWS clearly understood the threat and put out an ice storm warming around 5:30 AM.

With precipitation streaming northward and cold air in place we have mixture of snow over the north Sound transitioning to sleet in the central Sound and freezing rain in the south.   There are reports of 1/2 inch to one inch of freezing rain in the south and southeast Sound area (e.g., Olympia, Puyallup), with many downed trees and extensive power outages (over 100,000 customers reported by Puget Sound Energy, Tacoma Power, City Light).

Here is a neat figure showing the winds and temperatures in time over Seattle (time increases to the left, height in meters).  You can see the southwesterly/southerly winds aloft associated with warmer temps, a thin layer of southeasterly air below that, and cool northerly flow near the surface. You can also see the  descent of the freezing level over time.


At noon the back edge of the precipitation area (image) is apparent offshore, but clearly we have several hours more of this moderate snow/sleet/freezing rain event.


By tomorrow morning the winds should shift to the south at low levels with warmer temps.  The end.
Picture courtesy of Puget Sound Energy

Icy Seating at Sea Tac: Picture Courtesy of Seattle PI

80 comments:

  1. Very nasty 1/3rd inch ice layer in Tacoma's North Slope on top of eight or nine inches of snow. Ridiculously treacherous side streets will take a long time (maybe two days?) to de-ice even after it warms up. Beautiful ice-coated trees though.

    ReplyDelete
  2. Cliff - this is my first comment ever on your blog.

    I want to tell you that even though you say it's not your "profession's finest hour" it is still a fascinating and exciting event, and I am indebted to your honest and intellectually-informed weather updates. The fact that all of this information is at my fingertips is thanks to your dedication to the field. I turn to you first for weather predictions, and that won't change. Thanks for all you do!

    ReplyDelete
  3. It's been a good show all around. Thanks for all the updating, it has been appreciated at this residential outdoor education center.

    ReplyDelete
  4. Where's my snow tornado? :) http://www.youtube.com/watch?v=dM0Jynoflzo

    ReplyDelete
  5. So does this mean that the "warmer" temps for tomorrow won't be enough to get rid of this ice? I have a flight tomorrow afternoon and I starting to get nervous.

    ReplyDelete
  6. Once the storm is done, I will be curious to hear your overall impressions of how having the coastal radar improved information and predictions for this event. What did we know / know earlier that we would have without it?

    ReplyDelete
  7. It's been snowing here in Port Angeles. Just snow, mostly light, but not stopping...

    ReplyDelete
  8. Thanks Cliff! It was a nice surprise to see it start snowing again. We were expecting rain all day today and so far we have gotten almost another inch! (Bainbridge Island) . Praying for another school cancellation!

    ReplyDelete
  9. Snowing in east Lake City for the last half hour -- real snow, not sleet. The boot impression I made last night in the 6-inch snow in my backyard is now only about 4 inches deep. Very beautiful but I want to get OUT of here!

    ReplyDelete
  10. Thanks for the continual updates, Cliff. Having information is better than nothing, and even if I am stuck in my house one more day...I know why.

    ReplyDelete
  11. Well, we had a better forecast than a few years ago. One thing is for sure, we had a multitude of forecasts in the past 72 hours. Way more information than the average lay person could comprehend. With the age of the internet, some media is current, others not so much.
    One thing's apparent to me. Many of us have become complacent about preparing for winter weather events. Remembering back to the 1992 ice storms that wracked our area out here on the Key Peninsula in western Pierce County, with extreme damage from fallen trees and limbs, power out for a week with subfreezing temps, this is relatively minor event. Yet, many in the community have little in the way of supplies and equipment to cope. With many of the side roads deep in slush and ice untouched by county crews , trees snapping off onto cars and roofs, tomorrow's rain will be a miserable end to a miserable snow event out here.
    But that's not YOUR fault. We have appreciated your insights about the weather, the forecasts, and your humble candidness. Thanks.

    ReplyDelete
  12. It is still snowing steadily, big fluffy flakes, here in Lower Queen Anne - it switched over about 10 am this morning from freezing rain. Not sure which I like better but at least a fresh coat of snow will make sledding again today possible :)

    ReplyDelete
  13. The saving grace in Olympia right now is calm winds, otherwise trees would be falling all around. Ice continues to build.

    ReplyDelete
  14. I love the profiler graph. That is a beautiful piece of data visialization, plotting 4 elements in a single graph: time, altitude, temperature and wind direction. Fantastic. Thank you, too, for your ongoing diligence.

    ReplyDelete
  15. Thanks for the blog updates! It has been great getting the regular commentary on what's going on. I'm just wondering if we are going to get out of this ice today, or if we have to wait until tomorrow morning. This is brutal. Fortunately we still have power.

    ReplyDelete
  16. Thanks for all the great updates during this historical event, Cliff. While this may not be the finest hour for the profession from the perspective of forecasting, I can only imagine how much you guys are learning from the event.

    Just noticed that Langley Hill seems to have gone offline. Weird.

    ReplyDelete
  17. have really been intrigued following the reports throughout all this. thanks for keeping us informed.
    in the talk about the 'ice storm' I haven't herad references to sleet. is it not sleet? that's what they called freezing back in atl, when I was growing up

    ReplyDelete
  18. I wish I could send a weather balloon/sonde up at my house to see what the profile is. It was 26F in north Shoreline most of the morning and now the temp is drifting up to 27. Going on 1.5" of new snow @ 1:10PM. Sure glad it isn't ice!

    ReplyDelete
  19. Still snowing pretty heavily in Meadowbrook, 35th and 98th at 1:10 PM. So no school tomorrow too you think?

    ReplyDelete
  20. Spanaway and Puyallup area. Our freezing rain has turned into a mix of ice rain and snow now. We can hear it tinging or pinging off the windows. It's getting heavier too.

    Also, LOTS of branches are falling off the trees. Some of the taller trees are leaning very heavily over now, I heard reports from my Mom in Redmond that they are seeing trees fall over and lots of branches down there too (they live near Microsoft in Redmond, with a ravine/stream/greenbelt in their backyard.)

    This is quite exciting!

    ReplyDelete
  21. Cliff, for those of us lucky ones North and Northwest of Seattle who are getting snow - will we see this turn into an ice storm later this afternoon or evening as well?

    Or will it just turn to melting rain?

    KW

    ReplyDelete
  22. At the age of 54, I've lived in lots of places and heard and seen lots of weather forecasts. I can't remember any as wrong as the ones I've read in the past 48 hours.

    At this point, I think all meteorologists ought to say, simply, "We don't know what the hell's going to happen, or when."

    Face it, Cliff, with this storm all you or any of the rest of them are able to do is tell us what has already happened, and why. It's interesting to me, but there hasn't been a forecast out there worthy of the term.

    ReplyDelete
  23. One thing I'm finding so strange is that the radar doesn't seem to be understanding the precip over my area as just snow when it clearly is; it's interpreting it as some kind of wintry mix. I'm in Mountlake Terrace.

    ReplyDelete
  24. DIdn't see a link on your blog to mail you directly, but thought you might like to see this time-lapse video my friend Bryan did over 18 hours, beginning Tuesday afternoon through the snow that blanketed Seattle yesterday morning.

    http://vimeo.com/35295424

    ReplyDelete
  25. I second bethyp! I have never commented before, but I read your blog all the time. You make it very clear how difficult it is to accurately forecast NW weather, and revise your forecasts as time goes by and models become clearer. I love it!

    You can't always be right, but you CAN always tell us why the models were wrong. Completely fascinating, very useful, and wonderful reporting.

    ReplyDelete
  26. snow! tons! it won't stop! eek.
    and we are surrounded by the biggest, tallest trees in seattle! not sure how afraid to be... can't get out at all.

    we have snowsnowsnow coming down. this whole area (North Beach, Golden Gardens, Loyal Heights - all north of Ballard), the NW-est you can go in Seattle, has been completely ignored by news, by snowplows, no buses or mail for 2.5 days... LOTS of folks living around here! no mail since Mon either.

    i'm sure this is the largest concentration of the oldest trees in all of Seattle. lucky we have NOT - YET - had the rain/sleet/freezing rain HARDLY AT ALL since middle of the night - we'd all be destroyed by the branches! and may still.

    all the news channels seem to say for hours now, that snow is in tacoma or everett or I-90. NO - there is a bunch of snow FALLING STILL and CONTINUOUSLY here, in this part of N Seattle! we're gonna be in trouble as soon as it warms a bit or starts really raining. lots - it's pouring snow. at 1:50pm. will it really ever warm up or change to rain TODAY?

    ReplyDelete
  27. Exciting? One person has died, hundreds of thousands are without power, and thousands are outside risking their lives trying to help the rest of us out. I don't call that exciting.

    ReplyDelete
  28. It's been snowing nonstop in Bothell since around 6 in the morning. It was freezing rain before then.

    ReplyDelete
  29. Here in the Chehalis Napavine area our snow has compressed down to about 10 inches, from yesterdays 17. Temperature has hovered all day between 31-33. We fired up the tractor and further compressed the snow in the driveway - ducking fir branches covered with ice, and they do get heavy. We look forward to getting out tomorrow.

    ReplyDelete
  30. "By tomorrow morning the winds should shift to the south at low levels with warmer temps. The end."

    Since I see a "should" in there, I hope you'll forgive me for saying that I'll believe it when I see it.

    But this is why meteorology is an inexact science, no?

    ReplyDelete
  31. 2:12pm, and it's snowing BIG fluffy flakes in West Seattle now. I'm just above the Fauntleroy Ferry. Had freezing rain from early this morning until about a 1/2 hour ago. This is cuckoo crazy! Glad I'm able to work from home, and that I didn't make the attempt to go into work (Pioneer Square) today after all. I'm afraid the WS Bridge will be a nightmare by dark.

    ReplyDelete
  32. Here in Ardmore Park in NE Bellevue, it was raining and 28 degrees this morning, turning to mixed around 10:30 and then snow-only after about 11:30. Currently at 2pm it's 27 and snowing at a moderate rate, with about 1 inch of new snow on top of this morning's ice. Lots of tree branches are down. Everyone on our street is working at home.

    ReplyDelete
  33. This is no fun. On Vashon we have lots of plant damage and major limbs snapping because of the ice weight. There are many power outages. I like exciting weather, but hate ice storms

    ReplyDelete
  34. Bellingham has coped well with the very cold temps... getting around town has been very easy.

    Now that we're past this snow event, what's the likelihood of another one?

    ReplyDelete
  35. I knew we were in trouble when King-5's Rich Marriott said it was dangerous out there. Because he does not have the habit of sliding into drama, when he says we should be concerned, I listen.

    ReplyDelete
  36. Just heard the next weather system is coming in much faster than predicted and the cold wedge of air isn't moving and now we can expect snow through the night and possibly until sunrise.
    I bow to you snow cheerleaders. I admit it, I'm done.

    ReplyDelete
  37. Constant light/,medium snow at Northgate/Lake City Way for since before 9am (and still falling at 2:30). Added 1.5 inches+ to the area.

    ReplyDelete
  38. Freezing rain changed back to snow a couple of hours ago! 2-3" new inches in Woodinville. Temper1ature still at 26 degrees and holding

    ReplyDelete
  39. We have icicles now a foot long around our house on the west slope in Tacoma. Our side roads are impassable still at this hour. Glad to be safe inside.

    Compelling week weather wise tho'!

    ReplyDelete
  40. It's snowing here in Rainier Valley!

    ReplyDelete
  41. Interesting comments. It seems like the intrusion of the warm air actually stalled and reversed. Late this morning it was freezing rain in Madrona where I am, and plain old snow in Greenwood and Ballard. Then it switched to snow, and now it looks like the snow/rain line has moved further south even. This tells me that the warm air in the upper layers is being pushed southward by cold air, maybe also at the upper layers? What effect will this have on the next warm front coming tonight? How entrenched is this cold air now that it is clearly more tenacious than predicted?

    ReplyDelete
  42. Thank you Cliff for the updates on all of this.

    Do you think the Ice storm will continue up though Bellingham? or will it change to rain fast enough to miss having everything turned to ice?

    Thanks again!

    ReplyDelete
  43. Snowing hard now in Seattle's Central District.

    ReplyDelete
  44. This has been a fantastic week! I love coming to the blog and even if this "was not your profession's finest hour" it was still good. Way better than in years past.

    Understood that things have been shifting, but you have been keeping us well informed as things have changed. I'm impressed that things have gone as they have.

    It finally changed over to just snow here in Fauntleroy about 1:00p and is snowing pretty hard now. Almost an inch of new snow in the last two hours. This is my idea of a good winter storm!

    Thanks again Cliff, it's all appreciated.

    ReplyDelete
  45. No freezing rain at all today here at 75th and Fremont in Phinney/Greenwood (there was some last night), it has HOWEVER been moderately snowing since around 8am without stopping.

    ReplyDelete
  46. To echo an earlier comment "Thanks for all you do." Port Townsend - light snow all morning until noon. On ground accumulation where I live (Uptown) 6-8 inches. Temp is 26-27F. No wind.

    ReplyDelete
  47. Thanks Cliff you are the weather person that I turn to the most.

    ReplyDelete
  48. It is almost 3 PM and we still have snow coming down here in Ballard. It has warmed up a little to 31 dgrees from the 28 degrees it was at 11 am. Overall it has been a nice change of pace for Seattle. I rather like it.

    ReplyDelete
  49. I appreciate all of the updates. I don't expect snow forecasting to be an exact science, so I'm not at all disappointed when it's not accurate. A snow event is a fascinating thing, and it's interesting to learn about how it all happens - or rather how all the factors that go into it make it happen. Most of us wanted snow, and we got it! (I hope that Leah the dog has found a little shelter to be under; animals can be quite resourceful in that way).

    ReplyDelete
  50. Thank you, Cliff, for all the posts about this weather event, and for the various levels of detail imbedded therein--broad brush for people like me and technical, in-depth analysis for those who love that.

    Up here in Greenbank we often sit on the edge of weather systems, and your blog helps me to understand what is going on. I'm raising my mug of hot cocoa in your general direction (that would be south southwesterly, I believe).

    ReplyDelete
  51. @Northwest

    "Exciting" doesn't mean kittens and puppies, ever watch an exciting action movie?

    Here in Spanaway/Puyallup we are up to 1 inch of ice and it continues to come down, harder than this morning.

    ReplyDelete
  52. Cliff Rocks!! I live in Ellensburg and commute to Seattle...you are the definitive source. Thanks for all you do.

    ReplyDelete
  53. Are you sure??? :) Definitely snowmaggedon up here in the hills above Monroe...17 inches so far as of 3:30 pm today and it's still coming down. Your forecast has been much appreciated and followed by the staff at the local hospital.

    ReplyDelete
  54. I don't get this...the NWS is telling me "little or no snow accumulation late afternoon," but it's dumping snow in Rainier Beach right now.

    I have yet to see any accurate short-term forecasting for about 48 hours. I feel like my home weather station has given me more accurate short term predictions than the NWS. As a teacher (home today) and a weather watcher, I am feeling a bit disappointed with the reading of weather probabilities these last few days.

    What do the rest of you think?

    ReplyDelete
  55. What's surprising to me is just how wrong the forecasts were so close to the event. This morning, at 11am, I was looking at the weather.gov page, and they were still claiming we were going to see a high of 37 degrees today with decreasing rain.

    Now here it is, five hours later, it hasn't broken 30 degrees and it's still actively snowing. That's a pretty spectacularly wrong forecast for only being a couple hours out.

    ReplyDelete
  56. Long walk with the dog this afternoon in Lake Forest Park. Snowed all the way, gorgeous. Coyote spotted by my neighbor crossing Ballinger looking for a snack. Still some light snow falling. It's been a great break in, what would have been, the usual work week. The posts have been interesting and fun to read. Thanks Cliff.

    ReplyDelete
  57. I'm new to your blog, and to the area, and I must say that it's been an awesome read so far. Thanks for your honest updates and opinions. As for my area (Redmond), we've had continuous snowfall since about 10:30 am. Some freezing rain has been mixed in, but the snow hasn't stopped. Crazy.

    ReplyDelete
  58. Hmmm... interesting. The radar shows W. Seattle as "clear" (i.e. <5 BDz) but we definitely still have snow falling. So I pulled the resolution in closer, and sure enough, there are a couple of spots still showing up on the radar at 5-10BDz, right in our neighborhood. Gives some interesting insight into the resolution of the radar data.

    ReplyDelete
  59. Don't leave us now, Cliff, we need you! In Lake Forest Park (I know this is your neighborhood) we had freezing rain early which turned to costnant snow which stopped about 4pm. But the temperature hasn't started to rise yet. Still about 25 degrees on my back deck....

    ReplyDelete
  60. This has indeed been interesting to watch. I am aware how hard it is to "predict" the weather and think that Meteorologists get the same kind of rap that Microsoft programmers do, the get blamed for the crash but never get any credit for how well things work 95% of the time. This is complex stuff. I imagine that this is one of the most complex systems to have moved through these parts in several years and that that has made for the unreliability of the predictive models because there is just too much entropy to allow for a series of consistent runs. Which brings me to my point...

    Could we be relying too much on models? What would a Meteorologist have forecast 30 years ago with only access to the satellite images and old school instrument readings? He might have said something like this, "We know that there is a big cold front from the north, a big warm from from the south, and a massive low pressure river of clouds headed for the boundary. Well, it sounds to me like the entire Pacific Northwest is in for some crazy weather, so crazy, in fact we cannot predict what exactly will happen, but it is going to be big and region wide. So be prepared. Areas that are closer to the warm front will see increased snow fall and an earlier change to rain and areas that are further north will see sustained snowfall with decreased amounts. This situation is also literally a textbook example of the conditions required for Freezing Rain, so be prepared for this in many areas. Again, the system is so big and there are so many factors exact predictions and timings are impossible so please be prepared for just about anything. And expect just about anything for the next week or so as these series of storm come barreling through the region."

    Now I am not a Meteorologist and expect that what I've said in the preceding paragraph can be greatly critiqued by those who know more than I but my point is that 30 years ago a forecast would have been much more based on the causal aspects of the actual conditions and a best guess based on experience would have been offered. With the models we have today that kind of knowledge and experience is less relevant because we are just looking for consistent model runs and a convergence of probabilities across the different models. One is a causal approach and the other is a statistical. Statistics correlate with reality but they do not cause it. At a certain point one has to decide when to shift gears. Medical Doctors are in the same situation. So much of medicine is based on statistics of outcomes across population samples it sometimes is hard for them to treat a specific patient with specific symptoms. The line at which one would switch gears is another topic but one which seems germane to the public's dissatisfaction with the weather forecasts. At a certain point the Weatherman just has to ditch the models and run old school and issue his best guess based on his knowledge and experience. In this case that might have been a better approach.

    Now, just to be clear, I am not critiquing Cliff, or suggesting that he should do anything different but am trying to illustrate the difference in a statistic and causal approach to science. Especially when the system at hand really is far to complex for adequate statistical modeling. I guess boundaries really are where the most interesting stuff happens. Just like this weather system.

    ReplyDelete
  61. Still snow/sleet mix.


    Almost all intersections have lost power. We've been without since 9, going to be a long nihht

    ReplyDelete
  62. It's 4:45pm and the snow is finally slowing to a halt in the Phinney/Greenwood area. Sadly, there have been no plows this way, but fingers crossed the city sends them - I have to get to work tomorrow! Thanks for all the reporting!

    ReplyDelete
  63. We had freezing rain only briefly this morning, then snow the whole day, with accumulation, here in Montlake.

    ReplyDelete
  64. 5:00, still snowing lightly in North Kirkland. A friend in Snohomish reports this via Twitter:

    We've had power off/on, massive surges, bright lights, explosive noise, power line on the ground, but no PUD shows up. The entire house lit up inside and out like I have never seen, the buzzing and exploding noises were deafening. We think an animal was killed at the line, but we don't dare look. Just very scary and cold when the power is off.

    ReplyDelete
  65. Getting dark now... temp is -2C with an easterly surface wind here in Fremont. Legendarily fine, the kind of which to brag about years hence, excellent, historic sledding conditions in our neighborhood today. The local pack of eight year olds is already weaving tall tales about sledding the "mother hill" on Palatine...and they should all fall asleep perfectly satisfied tonight... Thanks Cliff!

    ReplyDelete
  66. The City of Seattle has a web page where you can see a map of what's been plowed or deiced at http://web1.seattle.gov/sdot/winterweathermap/

    ReplyDelete
  67. Still stuff coming down in Judkins Park area.

    Still can't get used to the sound of winter weather here.

    Really glad I did not have to go any further than the yard waste bins today.

    Gotta call my mother who was determined to go out adventuring on teh bus today. Arrrgh.

    ReplyDelete
  68. Cliff, this is my first comment for you but with the way this winter is turning, probably not my last.

    I was thinking about a post you had last year that was a very similar situation. You saw models that were showing Seattle having one of the snowiest weeks in history and having record amounts of snow in the area. However, the storm veered too far north about 2 days before land fall and we only received rain, heavy rain.
    This system seems like a repeat of that but instead we were on the cold side of the jet, and today was an example of the North wind playing a huge role of keeping us cold and in extended snow.
    This pattern seems like it could hold for a while and we could be flirting with snow and cold air even though the models say differently.I'm in Bellevue and we are sitting at 26 and dropping. Yesterday we were predicted to be in the upper 30's today and tomorrow in the upper 40's, what if the wind does not shift to the South?
    The 3 month outlook calls for below normal temps and above normal precip, which leads me to think this could be a warmup for the next few months. I'm sure we will be depending on you again very soon.
    You have a very difficult job that can never be exact, Keep up doing what you do and I'll be following it more then any newscast or paper.
    Also, something that you don't hear that often I'm sure, Thank you!

    ReplyDelete
  69. Thank you Cliff, for all of your updates, and telling us the reasoning behind them. I second Seven's question on the "should" - do you think the mid-40s tomorrow is a done deal, or could we see the cold last one more day?

    You also get a mention in a very good Art Thiel post on the KING 5 website:

    http://www.king5.com/sports/sportspress-nw/137716863.html

    ReplyDelete
  70. Gotta watch this video of one of our friends mocking the king 5 guys... "Yellow Jackets" on King 5. http://www.youtube.com/watch?v=Yrji0TPxtTk&feature=youtu.be Very Funny!

    ReplyDelete
  71. So delightful here on Oahu's North Shore with light trade winds and about 80 degrees. I don't know how my home island, Sinclair Island, is fairing. It will be interesting to see when I get back.

    ReplyDelete
  72. Hey, Cliff, great blog - thanks for keeping the information flowing to us. Don't apologize for Nature not being predictable - you draw the best model you can based on everything you know so far, and you tell us that, and if it turns out that Nature plays a trick, so it goes. You did hedge your bets a while ago by saying that pretty much anything could happen depending on the path that the low took... and you were right, the low didn't take the predicted path.

    Thanks again for the informative blog: I feel as I have really learned something.

    ReplyDelete
  73. Those in your profession are not clairvoyant. You use the tools available and make a best estimation. It's impossible to know if a weather system is going to shift, drop, elevate...etc. Thanks for doing what you do, giving us what information you can (which is way more then we get from the "yellow jackets") and most of all, thank you for educating the masses on what is really going on above us.

    ReplyDelete
  74. Thanks for all the detailed explanations, and for taking the time away from your usual UW duties. Much appreciated by another UW faculty member!

    ReplyDelete
  75. The snow was fun but the ice is not. My power is out and a birch tree just fell over in the back yard. Can't wait for the thaw and restoration of power.

    ReplyDelete
  76. Meteorologists get the same kind of rap that Microsoft programmers do, the get blamed for the crash but never get any credit for how well things work 95% of the time.

    I won't get started on Microsoft, but as someone who has never been inclined to treat the weatherman as a pinata, I really have to say that this week was as bad as I've ever seen it for the forecasters and their credibility.

    We got lots of data but little by way of usable forecasts. Even right now, late on Friday morning, it's 10 degrees below the forecast low of the day. This has become comical!

    With the models we have today that kind of knowledge and experience is less relevant because we are just looking for consistent model runs and a convergence of probabilities across the different models. One is a causal approach and the other is a statistical. Statistics correlate with reality but they do not cause it. At a certain point one has to decide when to shift gears.

    I agree with that. I'm as much of a stats hound as anyone, but over the years it has dawned on me that statistical modeling has a whole lot less predictive value than it seems to have at first glance.

    What you tend to get from statistical modeling is a phenomenally sharp view of the past, and of the present. The future? That's at least as much a guessing game as it's ever been.

    The danger from the statistical approach to anything is that it breeds overconfidence, sometimes fatal. Past performance is never a guarantee of future results, and often not even much of a guide at all.

    ReplyDelete
  77. For Placeholder...
    When cold air is replaced with mild marine air in the 40s, a diurnal high or low temperature is not really there. The forecast for the low temp in Seattle is 41 for tonight--but that is the current temp--it wont cool off overnight as the wind comes up (and it will be windy later!).

    Places up by the border with the last bit of air that comes down the Fraser are still just below freezing, but that should not last. The front coming in this evening will scour it all away. In fact, if you look carefully at the mesoscale model freezing level, the model even scours out the valleys into the Cascades. But I don't know about that, at least at first. I think places like Concrete, Marblemount, and probably even Skykomish on US2 could stay with snow tonight. But...after the front moves through late tonight, the snow level ought to equalize, probably around 2000 feet Saturday in strong onshore flow.

    ReplyDelete

Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

Comet Viewing Tonight

 Tonight may be the best night this week to view Comet Comet Tsuchinshan-ATLAS in the western sky just after sunset. The biggest issue will ...