Thursday, February 24, 2011

Snowstuff


Right now there are a few snow showers, but nothing serious (see radar above). We will progressively dry out during the day and much cooler temperatures (twenties to high teens) will be experienced tonight.

I plan on writing a blog tonight about the quality of the snow forecast and the role of the media. Bottom line: the forecast was not as bad as some have been saying and people have to learn to live with some uncertainty in the forecasts.

For all of your amusement, here is a list of snow totals provided by the National Weather Service:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
1130 AM PDT THU FEB 24 2011

..STORM TOTALS FOR THE FEBRUARY 23-24TH SNOW EVENT...

THE FOLLOWING IS A LIST OF SNOWFALL REPORTS FROM VARIOUS LOCATIONS
AROUND WESTERN WASHINGTON THROUGH THURSDAY MORNING. THE REPORTS
LISTED BELOW ARE IN INCHES AND ARE A COMBINATION OF OFFICIAL SPOTTER
REPORTS AND REPORTING STATIONS AS WELL AS SOME PUBLIC REPORTS. THEY
ARE ARRAINGED BY COUNTY

CLALLAM
SEKIU 2.0 (AS OF FEB 23RD)
FORKS 4.0
SEQUIM 4.5
COVILLE 6.0 (AS OF FEB 23RD)
PORT ANGELES 9.5

GRAYS HARBOR
OCEAN SHORES 2.0
OAKVILLE 3.0
OCEAN SHORES 3.0
MONTESANO 3.0
ELMA 3.0
OCOSTA 4.0
ABERDEEN 4.0
MOCLIPS 5.0
COSMOPOLIS 7.0
QUINAULT 7.0
WESTPORT 7.5

ISLAND
FREELAND 2.0
SOUTH GREENBANK 4.0 (AS OF FEB 23RD)
LANGLEY 6.0
CAMANO ISLAND 7.0
OAK HARBOR 9.0 (AS OF FEB 23RD)

JEFFERSON
PORT LUDLOW 0.5
CHIMACUM 0.7
PORT HADLOCK 3.6
PORT TOWNSEND 5.0 (AS OF FEB 23RD)

HOH RANGER STATION 14.0

KING
SEATTLE WFO 1.0
MERCER ISLAND 1.5
AUBURN 1.8
SEA-TAC AIRPORT 3.0
WOODENVILLE 3.0
BELLEVUE (IN TOWN) 4.3
SAMMAMISH 4.5
CARNATION 4.6
RENTON 5.0
COVINGTON 5.0
BELLEVUE (2MI SE) 7.0
SNOQUALMIE 8.0
NORTH BEND 14.7

KITSAP
SEABECK 0.0
BREMERTON 0.1
OLALLA 1.0

LEWIS
ONALASKA 3.0
CURTIS 3.1

MASON
SHELTON 2.0

PIERCE
EATONVILLE 2.0
GIG HARBOR 2.5
BONNEY LAKE 3.0 (AS OF FEB 23RD)
PUYALLUP 3.0
STEILACOOM 3.1
TACOMA (3MI NW) 3.5
TACOMA (1MI NW) 5.0

SAN JUAN
FRIDAY HARBOR 3.0
LOPEZ ISLAND 4.0

SKAGIT
BELFAST 4.5 (AS OF FEB 23RD)
ANACORTIS 6.0
LA CONNER 6.0 (AS OF FEB 23RD)
CONCRETE 12.0
MOUNT VERNON 16.5

SNOHOMISH
BOTHELL 0.8
ARLINGTON 2.5
MARYSVILLE 3.0
LAKE STEVENS 3.0
EVERETT 4.5

THURSTON
ROCHESTER 0.5
GRAND MOUND 2.0
OLYMPIA 4.5

WHATCOM
BELLINGHAM 1.5

$$

46 comments:

lyn said...

I thought the accuracy of predictions was quite acceptably accurate. Based on predicted timing of snow showers, the lovely spousal unit and I ducked out early and attended a matinee. We emerged just as the first snow showers hit Redmond - mid commute as predicted. We were home in Fall City uneventfully before snow even arrived here. If you weren't paying attention, or if you expected even better precision, try timing the stock market to improve your appreciation of the ever-increasing quality of weather forecasting in the NW.

Brooke said...

I'm curious to learn more about this "snowshadowning" effect that we have seen on Bainbridge Island. While the rest of western Washington seems to be getting a nice blanket of snow, we have seen hardly a flake. However at other times in the past few winters that I've lived here, we seem to get hit hard with snow (like last November, and the December 2008 storm).

Scott said...

Learn to live with uncertainty, yes.

However I do not think a post like this one with "SHOWTIME" in its title and phrases like "could be fierce and significant snow the result" and "...tonight could get very interesting very fast if this boundary locks over someone. Watch the radar now...if will be very entertaining!" is sufficiently presented as uncertain.

We can reasonably disagree on how uncertain your use of the words "could" and "if" are. That's fine. But I've re-read this post several times and I can't read it as anything other than a huge miss for what I experienced in north and central Seattle over the past 22 hours.

senorbarboo said...

The highly unpredictable nature of the weather in the Puget Sound Basin is was makes meteorology here so difficult and amazing. I personally haven't learned how to extrapolate predictions from NOAA and others models, so I just give thanks for you sharing your very well defined thoughts on what your seeing.

Salokin said...

@lyn:
Despite what you apparently found, the weather on Mercer Island was very unpredictable. The school district was completely shut down due to a forecast of 1-3 inches on Wednesday. But no snow fell. In fact, the sun was shining most of the time. I for one look forward to Cliff's blogpost tonight.

windlover said...

The difficulty in predicting the weather is understandable. Today it was snowing quite hard with sunshine at the same time. When I checked the radar there was nothing there....wierd! And the tempurature would be around 33 when it wasn't snowing but would go up to around 37 when it did snow....isn't that the opposite of what it usually does? I thought heavy snow showers forced the cold air to the surface, dropping the temps....? Right now it's hailing....wierd day!

Morgan said...

Hi Cliff -
Love the blog. This may be obvious but on the issue of forecast reliability/uncertainty - I think its worth pointing out that when it comes to snow (or extreme weather events) in the region there is a lot of tail risk in how we experience the weather (e.g. the alignment of conditions that bring about a lot of weather-related suffering but for which there are not good probabilities and exceed our ability to reliably predict). In other words, not all uncertainty is the same. There are order of magnitude differences between a situation where there is a 80% chance of precipitation when its 60 degrees out compared to when its 30 degrees out. I think implicitly, we all understand this. Local media outlets get it and love to exploit this dynamic for their benefit. However, seems like weather professionals still haven't calibrated a real useful way to talk about and deal with this issue. Not sure what the answer is here either, but curious for your thoughts.

Dwight said...

I think the predictions from the NWS were quite clear that accumulations would vary a lot from place to place.

When I looked at the UW's Seattle Rainwatch site for precip in the past 24 hrs this am it seemed to dramatically under report the amount of precip. For example, I live on the western edge of Vashon (Maury) and we received about 4 inches of snow overnight but the Rainwatch map said we'd gotten less than .1 of an inch of rain.

Vincent said...

Ok. so now it is snowing hard in down downtown Seattle. 3:35 pm. Flurry or onset of snowpocalypse?

Vincent said...

ok-- so at 3:36 is is snowing lightly but steadily in downtown seattle. Flurry or onset of snowpocalypse?

Josh said...

Folks...this is serious.

mig said...

The forecast was right on for my neighborhood of Tacoma.

Now we've got another hard snow shower and half gotten half an inch in the last hour for a total of about 3 inches.

mjtdawg said...

Only thing they got wrong was Seattle and kitsap county.The problem is that was by far the largest market. Weather is not a science but and educated guess. Although the times needs to stop with the headlines about going home before 3pm when it is 40 degrees and sunny.

eric said...

i don't blame you cliff... we as a society have placed these unrealistic expectations on weather professionals like yourself. much like mj's "man in the mirror", haters (or seattle-ites need to just "take a look at (themselves) and make a ch-ch-change."

thank you for all your hard work

Steve said...

The error in the forecast was issuing a "winter storm WARNING" for all of western Washington. That kicked in a huge response. Warnings should match what is actually happening or imminent. By 8am yesterday, the warning probably should have been dropped to advisory in a lot of the west.

eric said...

i don't blame you cliff... we as a society have placed these unrealistic expectations on weather professionals like yourself. much like mj's "man in the mirror", haters (or seattle-ites need to just "take a look at (themselves) and make a ch-ch-change."

thank you for all your hard work.

Skokomish said...

Umm, I thought the forecast was pretty much dead on.

People just need to complain about things, I guess.

mjtdawg said...

The only thing they got wrong was Kitsap county and Seattle. Unfortunately that is the largest market. No matter how you spin it( and kudos to Paul on KOMO for admitting it this AM). They screwed up the forecast in two large ways. They undersold the amount of snow to the north and oversold the snow to seattle metro. Weather is not a science but and educated guess and they quicker we all realize that they less let down you will feel. That being said weather professionals can do themselves a favor by not speaking in such certainties and also when it does not materialize don't use the same trick of saying it is delayed.

TVN said...

I felt in general the forecast was OK. It was always clearly stated that the snow would be banded. In the end we ended up with 2" here in Redmond which was within the very wide range predicted by the NWS. The timing was a bit off though as we got squat on the first round.

More broadly though, I have often thought I would like to see retroactive forecast analyses. I sometimes even save screenshots of the NWS forecasts to see how they turn out.

TVN said...

Oh and as for the media, I will leave that to others as I have given up on pretty much all TV news. Keeps the blood pressure down...

trav said...

I unfortunately had to drive from Sumner to Des Moines (and back) last night after 8:30. The drive was miserable, but I only bring it up to support Cliff's statement about uncertainty. Even over short distances (1-2 miles) the conditions and weather varied significantly. Right at my house the roads were still bare and wet, while less than a mile away they were covered due to heavier snowfall. Driving north on 167, the roads were decent until just north of Auburn, then absolutely miserable, then not too bad north of Kent. Precipitation shifted from rain to snow to graupel over short spans. There's just no way forecasts could provide that level of detail.

Avalon said...

I'm not even sure you should have to tell people that weather forecasting is uncertain, or that the media is so starved for something to meet the endless demand for content that they amp things up beyond belief, or even that we as media consumers encourage that behavior by seeking out the most overwrought and dire news we can find. It all just seems to be one relatively reliable part of the local weather.

deniseweldon said...

I live in Carnation. We got about 5 inches of snow starting at 5pm yesterday. I think thats pretty darn close to your forecast. We followers of your blog ain't complaining! Thanks Cliff.

deniseweldon said...

I live in Carnation. We got about 5 inches of snow starting at about 5pm. Pretty darn close to your forecasts methinks. No complaints here. Thanks Cliff, I no longer listen seriously to the network forecasters. You're my weather dude. By the way, loved the Nowcasts.

bug1111 said...

Forcast timing was spot on, although snow totals were more than expected 30+ inches.

bug1111 said...

Forcast timing was spot on, although snow volumes were a bit more than expected here in Darrington 30+ inches

JayDee523 said...

Cliff:

At the moment we are getting pretty decent snowfall in West Seattle above Alki, and it is still melting on the roads, but the air temp is 30 degrees and 96% humidity...As Han Solo said "I got a bad feeling about this, kid..."

Wx Enthusiast said...

Our 6 inches in Newcastle is already basically gone!!! Seriously?? What a disappointment. What is the point in getting a good snowfall if it's not going to stick around very long?

Ben said...

I agree that the forecast wasn't bad in the details, but the way the information is presented is alarmist/sensationalist and drowns out this nuance.

I'd also agree that this website was not immune from this sensationalist as well

Zathras said...

Steve said that the winter storm warning for Seattle "kicked in a huge response. Warnings should match what is actually happening or imminent"

I think that is fair--but to be sure, the forecast for Seattle was for temperatures in the mid to upper 30s--so most people would know that snow wouldn't accumulate on the roads. But it didn't snow anyway, the temp forecast was better than the precip forecast.
The southerlies also blew all day, not a good sign. They ought to have given out midday and then shifted to northerly several hours before they actually did. So details did not pan out, at least til evening when some snow showed up in the north part of the metro area.

It's true that Seattle metro area snow forecasts are among the least skillful.

Some decision makers in the metro area knew there would not be accmulating snow on the roads, others were less sure. And forecasts probably varied somwhat between Accuweather, the Weather Channel, the TV weather forecasters, radio, and the National Weather Service.

That said, I think it is more ideal to have an advisory up, and then when the snow shows up on radar, if it is heavy enough, then go to a warning. Obviously people who live where it snowed hard, got a better forecast and probably liked the warning and lead time.

Karima said...

I did think the forecast was pretty good as well. We all learn to live with variations, weather forecast is not an exact science.
Just a note that Mountlake Terrace has received more snow in the past 2 hours than in the previous 24. Everything had melted by 2 PM and now we are in a "winter wonderland" as my 4-year old says.
What are possible updates as to cold tonight and warmer?

Pen said...

North Bend rec'd 14.7" according to the NWS. Pretty well spot on. I thought the forecast was very accurate. It all happened a little later than predicted, but I can't find fault with that. I think Cliff did a great job. Between Cliff's blog and the NWS, we pretty well got hit with what they forecasted. I guess it depends on location, but I thought Cliff was very realistic in saying it could be area specific. Snow is always whiter on the other side of the Sound (Sorry.....couldn't resist)

THANKS CLIFF!!!!!! Now if I could just get my car out of the driveway......

julie said...

I live in Puget Sound area and have to drive to very remote spot in Eastern WA monthly and have done for six years no matter time of year.....unless passes closed. Had to fly once. Much prefer weather prediction that is more cautious than not. Being underprepared can be catastrophically worse than the slight annoyance of overpreparation. Along with an earlier writer I skip TV news. I rely on Cliff Mass, NWS and WSDOT predictions and cameras. WSDOT is great service especially in remote areas that don't have population to support news organizations. Also have weather band radio in the vehicle which is great when in the large tracts of WA that don't have cell phone service.

Jessica said...

When Cliff says "...tonight could get very interesting very fast if this boundary locks over someone. Watch the radar now...if will be very entertaining!" -- I think he was pretty clear.

Locks over someone. Watch radar.

IE - It can strike anywhere; it's in progress.

It feels to me like some of us (myself included) are suffering post-storm-excitement letdown. We clung to the windows at work & home; is it here yet?! I've been so freaked out by the predictions at the BEGINNING of winter that this season would be a doozy for the lowlands, that I sold my little sedan for an AWD.

I'm frequently grateful to Cliff for his work. And willing to acknowledge that variances will happen over our lovely NW terrain.

steph said...

I for one was grateful for the this-could-get-serious forecast. It prompted me to leave work early and stay off the roads once I got home to the Renton area yesterday. And thank goodness. Even though only some areas got hit hard, even though there was plenty of advance warning and supposedly the DOT was ready with the deicer and salt, sure enough, I-5 was a mess in the Seatac/Southcenter/Tukwila area yesterday evening, and the only reason I wasn't out there is because the earlier forecasts convinced me to take cover.

JewelyaZ said...

Cliff's forecast was exactly right for us... 5" here @ 210' elevation just to the west of Lake Sammamish at SE 3rd in east Bellevue (Phantom Lake neighborhood).

The timing was off by a few hours but it was easy to watch the winds shift on the charts and see that it wasn't going quite as quickly as the forecast originally called for.

I think people enjoy being excited about weather... me included... I am a bit of a second grader, rushing to the window at work to see the SNOW!!!! and we goad weather people into the sensationalism they give us. Cliff tempered his human excitement with some of the things that could stall or wipe out the potential snow and if you read all the words that he posted, the info WAS there.

I hate driving on icy roads and I'm glad we didn't get walloped. I've got things to do... thanks, as always, Cliff!

Neil said...

The forecast was quite good for Port Townsend yesterday. And by forecast I mean the NWS and Cliff's. We had a skiff of snow in the morning and a very heavy storm (5 inches in 2hrs!) in the late afternoon as the artic front set up.
When it comes down to it weather forecasting is trying to predict the future. Let that sink in: predict the future. So I feel it best to kind to the forecasters considering the enormity of their task.

Ian said...

It snowed lightly/moderately all day here in Sequim and remained below 30 degrees inhibiting melting. So we now have a grand total of 7". In fact, it's still snowing.

To me the uncertainly comes in because it is impossible to predict exactly when and where a low will form along an arctic boundary, where it will go, and how strong it will be. Subtle differences in strength, track and timing mean major differences in who gets snowed on and how much. I get the impression this one developed and moved much more slowly than originally expected from a forecast based on a model blend...seems to be on the move south again now though, finally.

Glenn said...

Well, Seattle may have dried out this afternoon (Thursday). But in Port Hadlock we had steady snowfall from around 2:30 to about 6:00. It warmed up first, so there was little accumulation. But it was a few inches (2 - 4) of high quality fluffy, cold temperature powder.

Glenn,
Marrowstone Island

mainstreeter said...

The NWS forecast was correct in my neighborhood, y'all just need to move

TVN said...

Scott's just grumpy because he didn't get enough snow where he lives. And yet Cliff clearly stated "if this boundary locks over someone." It did lock over some people and that was certain. It just wasn't clear where it was going to happen.

I don't mind not having gotten that much here - I like my snow to stay in the mountains.

weatherlover said...

I was fine win the bad forecasting. Instead of the 4 inches or less that all the networks forecast or even the 6 inches that was NOAA's original forecast for skagit county we got 11 inches. They forecast snow so we were prepared and getting more snow, in my opinion, was a win-win situation.

Bonnie said...

Downtown Ellensburg didn't get much snow. Went into town this evening & you could still see grass poking up through the snow, so probably barely an inch. But our house is about 7 miles west of town, up near the edge of the mountains and we got about 6 inches.
Winds were out of the south all day at about 15 knots. Down to only about 3 now, but I think it's supposed to get windy again tonite (nothing new for Ellensburg ... it's always windy here).

Dale said...

VINTAGE Jim Forman clip just seen on Kong news at 10. Surely it will be replayed again at 11 on King5, assuming he has not blown away by then. I would've recorded, per Professor Mass's request, but lack the means. Perhaps another can undertake this noble task?

Josh said...

WINTER STORM WARNING:
Winter weather event having more than one
predominant hazard (e.g. heavy snow and wind)
NWS Seattle Office

The winter storm warnings for the whole forecast area was right for the current "reactions of our times" We complain if we are slammed and immobilized by heavy weather after not getting told the perfect forecast from an imperfect science. SO the NWS shoots for the worse case scenario to cover all corners. It is a tough game to play. Whether its hurricanes or snowstorms forecasting these days can change the economical, political and security landscape with the posting of a forecast product. A wide area winter storm warning was perfect due to how fast our current culture gets flustered with a marginal storm. And after snowgate forecasting might have become political. I hope not.
_________________________________________

‘What do you think Stagg?’ said Eisenhower.

‘I hold to my forecast, Sir, breaks after dark tonight.’

He clapped me on the shoulder and said,

‘Good, Stagg, hold to it’, and went out smiling.
June 5th 1944 right before dday.
___________________________________

Zathras said...

Josh--I don't think it is quite right to say "the NWS shoots for the worse case scenario to cover all corners"

Forecaster bias does creep in from time to time, but it is not nearly the problem you might think it is. I think the biggest hurdle to imroving skill is that there is too much focus on creating a 'suite' of forecast and products, and too little on identifying the correct meteorology--the problem of the day and getting the basic forecast right.

Of course Cliff has the luxury of identifying the important meteorology, without being saddled with grunt work and distraction. Cliff is a good forecaster, he certainly beat me years and years ago when I was a student playing the spring forecast league.

The UW models are a terrific tool by the way, 'dprog/dt' is a nice one that I'll mention...it helps most of the time. However for this past system, for the metro area, dprog/dt actually worked against us in that the change with time of the snowfall forecast was for more snow over Seattle on those last two runs--although mostly on run 4 of 5 that he has posted on his latest entry. Bad luck that.

The 4km shows distinct rain/snow shadowing Saturday afternoon and night...when we make the transition to lowland rain again. Areas outside the Puget Sound are have some snow here and there, always interesting to follow the 4km.