Wednesday, April 17, 2013

Snow Totals Range Widely Over MSP According to Local Forecasters

In expectation of the latest (and last??) winter shellacking of the year, forecasters placed their bets for snowfall accumulation from Thursday into Friday. KSTP was the most aggressive with the storm, with Dave Dahl showing 7.5 inches of snow. KARE forecast a mere 2 inches of snow while WCCO essentially predicted 3 inches for the central core of MSP. The NWS (weather.gov for KMSP) appeared to forecast 2 to 4 inches of snow yet maintained a winter storm warning. Fox9 weighed in at 1-4 (2.6 on the infamous snow meter) on the 9 p.m. newscast.

We interviewed Tom Novak from Novak Weather this evening to get his latest assessment of the storm. That video can be seen here.

We'll try to update forecasts as we sight them. Commenters, please feel free to detail the forecasts you see.

We find the NWS forecasts very confusing. Per the graphics below, a winter weather advisory is in place for zip code 55116 (St. Paul) with a total snowfall (if you add things together) of 3-5 inches. However, for KMSP, a winter storm warning is in place yet the forecast snow accumulation is lower. If anyone from the NWS reads this blog, we'd love to better understand what's going on here.



75 comments:

  1. The insight above about NWS, if I'm understanding the question correctly,is related to the two different advisory areas in the metro. On the east side we have a winter weather advisory which brings less snow. Usually no more than 6 inches. On the west side we have a winter storm warning which usually brings 6 or more inches. This time of year with extreme temp contrasts, a matter of 40 miles can mean a huge variance in snow totals based on proximity to low and the powerful rain and Tstorms just to our south. Id say 4-6" maple grove area and 1-3" for SE metro. Thanks for letting me share.

    Bo

    www.boknowsweather.com

    ReplyDelete
  2. So, is everyone enjoying their severe weather preparedness week? ;)

    ReplyDelete
  3. Also, snow totals this time of year, even if 6" falls, it is constantly falling and compacting as it is close to wet slush. 6" may end up looking like 3" by the time it's done and settled.

    ReplyDelete
  4. I see two limiting factors with this snow and Bo touched on both of them. The combination of warm temperatures between 32-35 and that most of this snow will now fall during the day, means it will compact and melt as it tries to accumulate. The other is the severe thunderstorms to the south that will also help to rob moisture from this system. I'm thinking 3-6" across the metro, but wouldn't be surprised if we stayed on the lower end of the that range closer to 3-4".

    ReplyDelete
  5. Sleet/rain mix at this hour in Burnsville

    ReplyDelete
  6. Sleet mixing with rain in St. Paul as well.

    ReplyDelete
  7. Sleet/snow in Rosemount

    ReplyDelete
  8. My preliminary snowfall forecast. Let me say 1st of all I am going with a ensemble forecast that includes the 4/17 12z Euro, the 4/17 18z Reg Gem and the 4/17 18z 4km Nam.

    here is the 18z Reg Gem snow water equivalent.

    http://meteocentre.com/models/gemreg_amer_18/accum/SN_000-048_0000.gif

    notice the orange colors over the central to se metro. That is somewhere between 25-30mm which if I use 27mm equates to about 1" of snow water equivalent, based on a snowfall ratio of 10 to 1 that will equal 10" of snow, but the ratios will be lower than that.

    Now lets look at the 4km Nam. Once you open the link, enlarge it and you can see what colors (above the map) depict how much snowfall would fall assuming a 10 to 1 ratio.

    http://www.meteo.psu.edu/~fxg1/NAMSFC4US_18z/snow60.gif

    I can't show accumulating snowfalls off the Euro, but trust me it looks a lot like the other two.

    So therefore I think the heaviest snow will fall 20 miles either side of a line from Eden Prairie to Stillwater.

    Snow falling from the sky should be a wide spread 6-11" across the metro, but if snowfall reports are correctly reported to MPX at 6 hour intervals (to allow for a proper amount of compaction) I would expect that the reports will show 4-8" across the metro. I believe that Dave Dahl may be right. Therefore I believe the entire metro should be under Winter Storm Warning.

    I will post my final forecast later tonight or early tomorrow morning.

    ReplyDelete
  9. Plymouth Weather LoverApril 17, 2013 at 10:25 PM

    Bring it randy!!!!

    ReplyDelete
    Replies
    1. Hmmm.....PLW as for what May, may bring, please don't ask me to Bring it!!!

      Delete
  10. I would love to see Duane's take on this snowfall event. I know that the tall drink of water has met Bill, I'm sure that Bill wouldn't mind a second video be posted like he did a few weeks back. Or possibly a video on the warm up.

    ReplyDelete
  11. The 0z 4/18 run of the RPM model is hinting at what I posted above,
    possible heavier snow through the metro, all of the metro.

    ReplyDelete
  12. Anything over 4" is too aggressive, surface is too warm and main(heavy)band of snow will skirt to the north and west of the metro!

    ReplyDelete
  13. Sven won't even acknowledge that 1/2 the Twin Cities is under a Winter Storm Warning. "WSW north and west of the Twin Cities." Somebody should explain to him that the metro area - and Hennepin County - extends beyond his little inner loop.

    ReplyDelete
  14. Best 'Spring' ever!

    ReplyDelete
  15. And MyCast has added snowflakes to its graphic forecast early next week as well. I like snow, but this is getting stupid.

    ReplyDelete
    Replies
    1. Yep! @Bill your thread read "and(last??)", good use of the question marks because snow is a possibility Saturday night/Sunday morning and again Monday night/Tuesday morning, even in the metro. Temperature profile those nights will be near the critical freezing mark so don't be surprised if you see more snow.Maybe you can hit up Mr. Novak on that possibility, looks like the 50+ degree is getting pushed back till at least the 25th/26th.

      Delete
  16. Pretty sure the WS.W for Hennepin County is due to heavier snow amount across the NW half of it. Look at these graphics, the heavy snow is pretty much just out of the 494/694 loop. So yea, while area of metropolitan area are forecast to get WS.W level snow, in reality you're talking MAYBE 5% of the MSP area and even then no more than 50% of Hennepin County.

    http://graphical.weather.gov/sectors/mpx.php

    ReplyDelete
  17. Plymouth Weather LoverApril 18, 2013 at 1:40 PM

    It is coming down so hard--amazing. I hear that schools are getting out like crazy just beyond the west metro. I think the word "bust" won't come out with this one!!

    ReplyDelete
  18. Yea here in maple grove we have about 2-3 inches already. Quite impressive, even sticking to the pavement! Looks like another 4 plus on the way. I noticed the NWS is upped the totals for the area.

    ReplyDelete
  19. 2" solid compacted on the hard in Minnetonka.
    Wet, sloppy, mushy, heavy...just great (not happy) pain in the butt kind of snow.
    MNPLOWCO

    ReplyDelete
  20. There definitely will be some bad grades for this event. I think Kare was the furtherest off!

    ReplyDelete
    Replies
    1. Kare 11 predicted 2-3 inches for my area as of this morning (west metro). We were at 2-3 inches by 2:00, several hours before most forecasters originally expected the snow to start here.

      Delete
  21. 3.5" compacted in Minnetonka now.
    MNPLOWCO

    ReplyDelete
  22. Snow started late morning in Carver County and has fallen HEAVILY since then. Everything has come to a stand-still. It is at least as bad as the height of last Thursday's storm, and this one looks like it's going to spin right over us. Most impressive: the wind. We have near-blizzard conditions, even in populated areas!

    ReplyDelete
    Replies
    1. Agreed. The wind is managing to move the wet snow to a degree I didn't think was imaginable.

      Delete
    2. The flakes are very small and icy, not as heavy as the consistency of the snow once it lands. Current conditions have us about 5 mph too low to be considered for a blizzard warning.

      Delete
  23. I just checked the NWS website and one of their own employees already measured 6.0 inches in Waconia as of an hour ago. Despite that, Belinda Jensen just forecasted a 4-6 inch grand total for us. I don't understand why they are having such a hard time adjusting their forecast!

    ReplyDelete
  24. Im up in Otsego and it is nuts with the wind! Probably only 2 inches on the ground but it would be more like 6 if this was winter..he he he. I just hope the wrap around keeps us in it. I want to go do the driveway and drink beer one last time.

    ReplyDelete
  25. Is the dry slot going to cut off the snow for the central metro?

    ReplyDelete
  26. Kare 11 should get a poor grade for this storm, never fully acknowledging its potential.

    ReplyDelete
  27. During the 6:00 newscast they upped us into the 7-inch range. If we had 6 inches at 4:00, we must be nearing 8 inches now. It's been snowing an inch/hour or better since it started at 11:00. I give them an F so far. They were practically mocking/dismissing the metro portion of the Winter Storm Warning as recently as this morning.

    ReplyDelete
    Replies
    1. "They" = Kare 11.

      What are other networks saying? Are they still being conservative about west metro amounts?

      Delete
  28. 'Deformation'/pivot access now right over the MSP metro. This is an indication that the storm is at the mature point for the MSP metro and will soon start to move east of the area. In turn, snow will quickly decrease in intensity later this evening. Until then, expect another good 2 to 4 hours worth of accumulating snow, especially over the NW 2/3 of the metro.

    Obviously, there is an extremely sharp gradient to the snow as you head southeast of the downtowns. Some areas of Hennepin county will receive 8"+ of snow while areas of Dakota county may only get 2"-3".

    In general, this was predicted well by the models. There is no reason why weather forecasters shouldn't have hit this one on the nose. On the other hand, some weather forecasters only look at their favorite computer model and they live and die by it. They take that solution and run with it without attempting to create a consensus with all models. No one model is king; I've learned that the hard way over the years.

    ReplyDelete
  29. It took all winter and 1/3 of spring, but we finally got the perfect track for a low pressure system. The Wind Map shows the center of circulation north of Madison, WI. Beautiful!

    ReplyDelete
  30. The snow is beautiful! Where was this the first half of winter?!?! I'm going to enjoy the snow tonight, and then start looking forward to some warm, sunny spring weather!

    ReplyDelete
  31. 4.5" to 4.75" as of 7:15pm here in our driveway bordering Edina/Hopkins. Took multiple measurements...The total variance was about 1/4 inch, depending on location.

    Sure is a surprise, as Kare 11 was more or less downplaying this one, with a 2-3 inch estimate here in the metro.

    ReplyDelete
    Replies
    1. 8:30pm- Just took another measurement. We're at 5" now. So I'd say it's falling at ~.25"/hr or so. Tho the wind has picked up a bit, and the flakes seem wetter/smaller.

      Delete
    2. 6" as of 9:35pm. (In 2 out of 3 measuring spots, It's about .10" away from hitting 6". So I'm calling it 6") Which makes it 1" fallen (or close to) in the last hour...a significant uptick from the previous hour.

      Garbage day at our house tomorrow...#yikes

      Delete
  32. Only 2.9" reported at MSP.

    ReplyDelete
  33. I just shoveled for the second time, 3-4 more inches between 4:00 and 7:30 and still coming down hard. That would put the Waconia area at about 10 inches total, right in the middle of the rotation and heaviest snow. The snow is noticeably lighter now than it was at 4:00 too. We will easily see a foot total, if not more, which would be 4-6 inches more than even the most aggressive estimates I saw.

    ReplyDelete
    Replies
    1. *CORRECTION: lighter as in weight and dryness, not as in rate. It's still snowing heavily, possibly still at a rate of an inch/hour.

      Delete
  34. NWS is saying 3-5" nighttime accumulation for my location...Saint Louis Park. Does ANYone think that's really possible? That would be amazing!

    ReplyDelete
  35. We've received another inch or so since I finished shoveling just before 8:00. Coming down even harder now than it did for most of the day. Can't make this stuff up.

    ReplyDelete
  36. Plymouth Weather LoverApril 18, 2013 at 9:15 PM

    Pants are wet. And not from shoveling!!!

    ReplyDelete
  37. Lookin like another banner weekend here at the north pole! High 30s, maybe 40 if we're lucky. WTF.

    ReplyDelete
  38. I'm about fed up, to be honest, and I'm a ski-bum winter-lover. But I also coach school softball and our entire season is going to be canceled at this rate. It's heartbreaking for the kids!

    ReplyDelete
  39. Plymouth Weather LoverApril 18, 2013 at 10:15 PM

    Looking back. Amazing that it can snow this hard during the DAY in April!!!

    ReplyDelete
  40. A very solid 5" in Highland Park, St. Paul. Tempting to call it 5.5".

    ReplyDelete
  41. One of the wildest rides I have ever taken...from Golden Valley to Eden Prairie, 169 was snow covered the whole way down, I always hear Paul Douglas say its going to be a white knuckle ride, well I think I just experienced one....it is snowing so hard and that wind combo I can only see the car in front of me also 2 cars I watched go into a ditch and there had to be about dozen in my 13 miles to EP.
    All I can say is this storm delivered big time! @8:30 was 6" in Golden Valley.....@10:30 its 7.5" IN Eden Prairie....all this and its one month into spring already...unreal!

    Happy plowing MNPLOWMOWCO!!! Who ever said snow can't accumalate on the hard in April,obviously doesn't have your job,be safe out there....this is some heavy snow!

    ReplyDelete
  42. Here's what Paul Douglas wrote in his blog that published late Tuesday night (close to midnight):

    A cold rain arrives later today, mixing with sleet, ice and wet snow tonight. An inch or two of slush can't be ruled out by Thursday, with a plowable snowfall possible north/west of the Twin Cities metro - but I don't expect quite as much weather-drama as last week.

    Horrible forecast.

    ReplyDelete
    Replies
    1. Amen.

      I'm glad somebody else noticed this. He spends so much time crafting promotions for his for profit companies thinly disguised as "weather news" in his blog. It's amazing nobody was there to update a terrible forecast all day today during a one of the biggest storms of the year. Strib readers were not well served on this one.

      And multiple ever changing forecast for every storm = major credibility issue.

      I guess if you put out 4 different forecasts for the same storm you can always say one was right?

      What a racket.

      Delete
  43. So last storm the forecast was over and people were angry. This one, amounts were under...and people are angry. It is almost as if predicting the future comes with inherent uncertainties.

    I'd love to have a thorough discussion on verification, if nothing else to provide a more scientific view point than is given by the drive-by posters here. I mean, just look at this map. If the storm had tracked just 25 miles further north/west it would have missed practically the entire MSP metropolitan area. 25 miles! That is half a county.

    ReplyDelete
    Replies
    1. Great point.
      Personally, last weeks storm was also a timing issue (for me). We were under a WS Warning for at least 24 hours b/w "lulls".

      Despiite the confusing forecasts shown at the top of this thread, NWS handled this storm much better than last week.

      Delete
  44. Hey, only 136 days until the unofficial end of Summer (Labor Day). This is the type of Winter/Spring that people decide to leave and never come back.

    Bill - you headed back to Kansas City this weekend for some Spring?

    Amazing to hear this wind and seeing it whip the wet snow onto everything. Despite the earlier onset of the sleet and snow than predicted, the NWS had some pretty good graphs Thu AM and made the right call adding Ramsey and Dakota counties to the Warning late this aftn.

    ReplyDelete
  45. I actually think most forecasters who mentioned 6" totals did pretty well. We actually had plenty of notice from most that this would be a significant storm.

    ReplyDelete
    Replies
    1. Dave Dahl and Novak and Randyinchamplin,get the 'A' grade from me.....everyone else was either too conserative or late to the party(IF YOU CHANGE FORECASTS DURING AN EVENT,ITS 'NOWCASTING', NOT A FORECAST)

      Delete
  46. 8.5" in Eden Prairie....still snowing moderately at this hour, at times heavy!

    ReplyDelete
  47. Flurries are all that remain at this hour.... but looking back... with precip/snow starting around noon yesterday,thats about an 18 hour contiuous snowfall in April.Pretty cool!
    Also rumor has it we will be in record territory for low max temperatures today and tommorrow as well as low temperature tonight.

    ReplyDelete
  48. So you thought this was it for the snow, NWS doesn't see it that way, heres what they have to say:
    Saturday night: chance of rain/snow before 1am,then snow likey.60%,up to 1" of snow.
    Sunday: rain and snow likey,becoming all rain after 1pm.60%,up to 1/2" of snow.
    Monday night: a 50% chance of rain and snow.
    Tuesday: a 30% chance of rain and snow.
    Wednesday: a 20% chance of rain and snow.
    Wednesday night: a 20% chance of rain and snow.

    The s-word isn't going away, keeps rearing its ugly head!

    ReplyDelete
  49. New model data suggests that it will snow every other day for the next 6 weeks. Temperatures JUST cold enough for snow each of those times. We may hit 60 degrees at the end of May, possibly early June.

    ReplyDelete
  50. I don't know how these "trained spotters" are measuring the snow. We got at least 8 inches in Roseville, and probably closer to 10. I cleared the driveway last night around 7.30 when there were already 5 inches. (I have to add, it was odd to be blowing snow in the broad daylight we have in mid-April. I'm used to doing it in twilight at best.) And then I had to do it again this morning after at least another 4 or 5 inches had fallen. The end of the driveway was completely blocked by the plow with heavy snow. The east side of the house had been sprayed by blowing snow.

    This is definitely the most epic April snowstorm I've seen. I'm too young to really remember the 1983 or 1984 storms. I think it's remarkable that April will probably wind up being the snowiest month of this winter, and it's not even a winter month.

    ReplyDelete
  51. I'm wondering what the rest of you think, but I've been in Minnesota my whole life, and although this April is obviously unprecedented, I don't know if it's that far off from the norm is it? I feel like I'm ALWAYS anxious for warmth in April.

    Anyway, just my two cents. Frustrating spring, but I'll take it over hurricanes, extreme flooding, and places that have no season change at all.

    ReplyDelete
  52. Who wants more snow???????????????

    NWS has 1 1/2" Saturday night.....AND.....Paul Douglas says rain changing to wet snow Monday with accumulations on lawns and fields. This is getting out of hand and I'm a snowlover.

    ReplyDelete
  53. Plowed 25 hours straight. We started plowing at 5pm on the 18th and finished at 6pm on the 19th. @big daddy, your sleep patterns are like mine...on the computer at 230am. "Sleeping is over rated". In the world of weather..it comes when it gets here and leaves when it's over...no clocks allowed. And yes! white knuckle driving, pulling 5 tons of bobcat and trailer through thick slop on the highway is nerve racking. We kept being pulled towards the ditch every few seconds.
    I hope we can put a fork in this. I'm really done with this weather pattern.
    Cheers, MNPLOWCO

    ReplyDelete
  54. It has been a very cold and snowy spring. Maybe summer will be better.

    ReplyDelete
  55. @MNPLOWHADENOUGHCO.....I work the graveyard shift(up all night, sleep in the day).Your a busy man these days and I hate to break this to you its not going away yet....I direct you and everyone to read this mornings NWS area discussion and view its new weather story graphic, in short we have at least two more snowfalls on the horizon.Tonight they have minor accumulations of 1-2" and for Monday night they call for 'possible plowable accumulations'(including the metro) with possible 2-5"+ in the discussion page.
    @Bill I think a few more Novak winter videos are in the offing!...what you say we shot for 7.7 more inches of snow and break the all-time MSP snowfall for the month of April.
    Go big or go home!!!!

    ReplyDelete
    Replies
    1. AAAAHHHHH NOOOOOOO !!!!! ( kicking boots around the room, dropping to knees, sobbing, shaking, )
      O.K. a bit dramatic but, come on.
      @big daddy... no wonder you are always up at night. Nice to know I'm not the
      only one NOT toasty in a warm bed at those late night / early morning's.
      I just decided to put my #@&$! January calendar back on the wall
      "CUZ IT'S 16 DEGREES OUT!!!"
      MNIWOULDQUITMYJOBIFIDIDNTOWNITCO

      Delete
    2. Too funny @ MNIRATHERBEMOWINGTHENPLOWINGCO!!

      Delete
    3. HA! True
      MN?CO

      Delete
  56. Mr. Novak where's your travel impact map for Monday? Is the metro in the moderate/high area?

    ReplyDelete
  57. We got a dusting down here in Rochester which melted by noon on Friday. I'm fine by that btw. :-) I see a lot of green finally mixing in with the colors of the grass.

    ReplyDelete
  58. New thread posted above. Also, for the latest video with Dr. Novak, go here: https://www.youtube.com/watch?v=YsBYAmnIVyo

    ReplyDelete