Good morning bloggers,

Another winter storm is taking aim on the plains states as a cold air mass has blasted south and is in place.  This is setting the stage for a winter storm to begin tonight.  There is a chance of some significant icing.  How much ice does it take to cause a problem? Let’s take a look.

Freezing rain is liquid water, or just regular old rain that freezes on contact with surfaces that are below freezing at the surface.  Frozen rain is sleet, or ice pellets, and very different from freezing rain.  The set up for tonight near Kansas City is for some snow, then sleet, then freezing rain to be the precipitation types.  There may be a period of snow at the very beginning of the precipitation, but a quick transition to the other precipitation types is likely.  How much ice accumulation does it take to begin producing problems?  Well, a thin layer 1/100th of an inch thick will cause many problems with slipping, sliding, and falling.  For potential power outages, less than 1/4″ of ice accumulation is not enough to cause any power outages. Let’s take a look:

Here is a Powercast from last nights data:

This forecast map shows that most areas may stay just below the criteria that would begin the concern for power outages.

Temperatures will be rising above freezing later in the day Friday, and the icing will immediately come to an end if those temperatures do rise to just above 32°.  I have experienced ice storms that stopped producing ice the second the temperatures rose to 32.1°.  It is incredible how delicate it is, as the freezing temperature is 32.0°. Once it rises above that number, melting immediately begins.

Here is the new HRRR valid as the precipitation arrives near KC:

As you can see, on this HRRR model, the precipitation begins as snow, and then is about to quickly transition to sleet or freezing rain.  If the snow can last for an hour or two, some accumulation would be likely before the change occurs.  Northern Missouri has a better chance of snow accumulation before the precipitation type changes.

Forecast for Arrowhead on Sunday:

What I just analyzed on the new NAM:

  • On the new NAM model, the precipitation doesn’t start until around 6 AM Friday.  If it waits that long, any chance of snow is low. The chance of snow would only arrive if the precipitation starts earlier than this latest model is showing.
  • On this new NAM, the precipitation starts as sleet, which would be bad for roads, but good for power outages.
  • By mid-morning, the sleet changes to freezing rain and ice would then begin accumulating on power lines and trees
  • By late afternoon, the dew points are forecast to jump to 32 degrees which would force the air temperature at the surface to be 32 or warmer and the freezing rain would then change to rain. The amount of freezing rain accumulation into ice is the big question, and right now it appears that it could come close to 1/4″. This would limit any major problems, but any longer duration of icing would begin causing bigger problems.

Thank you for participating and sharing in this weather experience.  Have a  great Thursday.

Gary

Gary Lezak

Author Gary Lezak

More posts by Gary Lezak

Join the discussion 109 Comments

  • Fred Smith says:

    Gary must believe we are going to get more ice than snow…while the NWS is just the opposite.

    What gives? Who will be right?

  • Bill in Lawrence says:

    Gary:

    Happy Thursday to you sir!! Hope you are feeling better!!

    Well, all the data at the moment for sure points that my post 2 days ago is going to bust. No…the data does not show a 2002 type event but .15-.25 of ice will for sure cause travel problems and school closings-that would be a significant winter event for this area imho. Yes…I did say there was a 25% chance of a significant event happening, but the overall tone of my post and the fact I said there would be frozen precip for only 2 hours makes my post completely wrong. Of course things could change..the cold air is not very far west and given Lawrence’s location it could pop above freezing quickly but all data points to even here in Lawrence with our SW location having some icing issues tomorrow that could cause real issues with travel etc.

    So I’m here to eat some crow a bit early LOL!!!!

    Have a great day everyone

    Bill in Washington Creek Valley in Lawrence

  • Bill Scott says:

    So NWS issues a winter storm watch yesterday and then overnight, changed that to an advisory. Are the thoughts trending toward this storm hitting east of the city now? Guess I have a hard time understanding the difference between a watch and an advisory when the forecast calls for a decent amount of ice.

    Hopefully this is long gone and roads have a chance to recover before the trip to Arrowhead. Lets go CHIIIIIIIEFS!

  • SnowGoPewPew says:

    I certainly hope the ice threat is very minimal. Even though I don’t have to drive to work anymore, walking could still be dangerous.

    Gary, did you happen to see my comment the other day about Google using AI to help forecast weather data with accurate predictions 6 hours before an event? Here is the link I found, https://www.theverge.com/2020/1/14/21065095/google-ai-weather-forecast-predictions-rainfall-research

  • Sean Mizell says:

    Am I out in left field here?!?!?! I don’t understand the talk of the NWS going fro a Winter Storm Watch to a Winter Weather Advisory, how that is downgrading the storm? I always thought that a Winter Weather Advisory is worse than a Winter Storm Watch, meaning more certain and worse weather with a Winter Weather Advisory. To me we were upgraded to a Winter Weather Advisory.

    • Gary Lezak says:

      I just added my analysis of the NAM to the blog. What I just analyzed on the new NAM:

      On the new NAM model, the precipitation doesn’t start until around 6 AM Friday.  If it waits that long, any chance of snow is low. The chance of snow would only arrive if the precipitation starts earlier than this latest model is showing.
      On this new NAM, the precipitation starts as sleet, which would be bad for roads, but good for power outages.
      By mid-morning, the sleet changes to freezing rain and ice would then begin accumulating on power lines and trees
      By late afternoon, the dew points are forecast to jump to 32 degrees which would force the air temperature at the surface to be 32 or warmer and the freezing rain would then change to rain. The amount of freezing rain accumulation into ice is the big question, and right now it appears that it could come close to 1/4″. This would limit any major problems, but any longer duration of icing would begin causing bigger problems.

      • Melanie in Shawnee says:

        Are temperatures expected to jump above 32? You say they will jump to 32 in the afternoon, but I know there is a very fine line between rain and freezing rain. What is the chance that temperatures don’t make it above freezing?

    • Three7s says:

      A WWA is very generic typically. We were actually under a WWA on Monday morning and I didn’t even realize it for a bit of freezing mist. In my opinion, a WWA Is virtually nothing.

    • Heat Mizer says:

      Because a WSW is in possible anticipation of a WSW, so when only an advisory is issued, it’s not as bad as it could have been.

    • Cody says:

      America should really just be like Canada in this instance and separate freezing rain into its own weather alert (Freezing Rain Warning).

  • Stl78 (winona,MN) says:

    Winter Weather Advisory will be issued for any amount of freezing rain, or when 2 to 4 inches of snow (alone or in combination with sleet and freezing rain), is expected to cause a significant inconvenience, but not serious enough to warrant a warning.

  • Josh Honas says:

    Refresh my mind on the criteria of Ice Storm Warning? I don’t feel like googling it. TIA 🙂

    • Three7s says:

      I believe it’s .25 inches of freezing rain or more.

      • Josh Honas says:

        Some literature says it’s 1/4″ and some literature says it’s 1/2″. So I believe it is the local NWS office’s discretion…

      • Josh Honas says:

        I would not be surprised to see an Ice Storm Warning Issued if more freezing rain pans out as opposed to sleet or snow…

      • Brian Graham says:

        Correct. A Freezing Rain Advisory is “up to .25.” A Warning is more than .25.

    • Ryan L says:

      From google
      “An ice storm event is expected to meet or exceed local ice storm warning criteria in the next 12 to 36 hours. Criteria for ice is 1/2 inch or more over at least 50 percent of the zone or encompassing most of the population. “

    • Heat Mizer says:

      lol…that would have been easier than asking it here and waiting for an answer.

  • Michael Casteel says:

    I recorded 4 Degrees this morning up here in Maryville, MO. BRRRRRR hoping February is above average temps! Be safe out there Bloggers,
    Michael

  • Jeff says:

    At least temps will warm to above freezing at some point Friday afternoon. It would be much worse if they did not. I’m not one to “root” for WSWs, and there have been times when WWA get upgraded to WSW when conditions change. Hopefully, tomorrow will not be one of those situations.

    Gary-
    If leading precip does not start until later early Friday AM like NAM shows, then that should be favorable for a shorter below freezing event I would think as the warm air timing would be about the same? While it may not start as snow, could it be a shorter event, a bit lower precip totals, and even lower risk for a severe icing event?

    • Jason Rann says:

      How certain are we that temps will get above 32? That is my biggest concern. The Mrs. is flying back from Michigan tomorrow and is supposed to arrive at 5:00 pm. Really hoping that doesn’t get screwed up.

      • Clayton Pfrimmer says:

        Is it possible that the colder air may be a tad stronger than anticipated? We are currently at 19 degrees on Lansing KS and 12:30 and it’s showing it’s supposed to get to 30 today.

    • Stl78 (winona,MN) says:

      -10 up here this morning if it helps to warm u up Michael.

  • Rodney Davis says:

    Gary based on your freezing rain map do you think this is why the National Weather Service in St. Louis is hesitant to pull the trigger yet and leaving the winter storm watch in effect? If these amounts are correct near Columbia I would think they would upgrade it to a winter storm warning, your thoughts?? Thanks

    Rodney (Ashland, MO)

  • Zach Kumke says:

    Sticking to what I said last night. Tomorrow will be a non-factor for a lot of the area. Some sleet. Some freezing rain. Roads will be slick but nothing too significant. I doubt we get even .2 or more of ice accumulation. Sleet should rob a lot of the total before the 3-4 hour window of freezing rain

    • Go Pack Go says:

      ^^ LIKE ^^

    • Brian Graham says:

      Sleet will rob from the snow, not the freezing rain.

    • MMike says:

      Zach,

      No snow accumulation at all in the city?

      You still sticking to the 22nd to 24th storm….”plenty of cold air in place for this storm” current data shows the cold air moving out around mid week and mostly a rain storm for most of the Plains. CMC has snow accumulation here but temps are well into the 30’s. (not cold) EURO is also warm after Tuesday next week. GFS warm too….

      The data shows what it has shown since early Dec. NO SUSTAINED COLD, shots of it, but nothing that stays around for more then a few days.

  • Miguel Alvarez says:

    Million dollar question for parents, kids, teachers: will there be school cancellations tomorrow? … How do you see this playing out?

  • Clayton Pfrimmer says:

    New 18z NAM came out with around .5 to .6 inches of freezing rain from Topeka to KC and more south…..

  • Hume Dude says:

    Still no arctic air showing up, GFS is now taking us through Feb 1st. Couple cold shots, nothing that can be called arctic though, not even close. Wonder if Gary will give up on that notion or stick to his guns? I argued a few weeks ago that since we haven’t had a true arctic shot yet, we likely wouldn’t get one at all this winter. I mean, the LRC has delivered a blow torch so far, why would it change now? With all of Feb looming I could be seriously wrong, but this ++AO++, it’s not allowing it to get this far south. Would be first winter in many without a real arctic shot

  • Heat Mizer says:

    Gary, Facebook Live tonight?

  • Austin Braddock says:

    can we make a suggestion that if you post a specific models forecast that you leave a link?

  • B77L says:

    KC NWS discussion: Will maintain the Winter Weather Advisory for now, given the
    uncertainty still in place at the moment, but may need to upgrade to
    an Ice Storm Warning for the overnight update if current trends
    hold.

  • Garrett Osbourn says:

    Hi res models bigger on the snow amounts, specifically HRRR, and RGEM

  • Kristi Harris says:

    Temperature is 25 at 4 not sure it will make it to 30 today how will colder temps affect this storm ?

  • Josh Duncan says:

    It seems almost impossible to say what precipitation types will happen when. Models are generally in very good agreement that there will be a mix of heavy snow, sleet, and freezing rain, especially early in the morning. The precipitation will gradually become lighter and transition to rain throughout the day.

    The amount of ice accretion (freezing rain) will be highly dependent on how much of the precipitation is sleet and how much is snow.

    Bottom line: Widespread travel impacts likely with the possibility of some power outages if everything comes together just right.

  • CJ Mac says:

    What is the difference between tropicaltidbits and pivotal weather?

  • Cody says:

    So, is the precipitation in south-central Kansas moving towards Kansas City ahead of schedule? Looking at radar on my MyRadar, precipitation (if it holds and continues it’s progression this way) looks to be in our area well before the current hourly forecast precip start times on most weather apps.

    Also, did we reach our forecast high temperature today or nah bro?

    • David Swartz says:

      It’ll take some time before the air is saturated. We have some dry air currently coming in from the NE with the cold air. The column needs to saturate first and then it should begin around 4 a.m. or so in the KC area

      • Gary Lezak says:

        I agree with your timing, and perhaps maybe starting an hour or so earlier. The snowy models, like the HRRR and RUC have my attention, but there just has to be a warmer layer just barely above freezing approaching at that time. So, will it start as snow, quickly change to sleet, then to freezing rain, then to rain with a chance of a thunderstorm? This is the exact opposite of the last storm that started with thunderstorms changing to rain, then freezing rain, sleet, and then snow. Isn’t that incredibly amazing, the exact opposite in this storm.

        I am heading into work soon. I will be doing the 10 PM newscast, and a FB live at around 8:45.

  • Josh Honas says:

    1st wave looks pretty healthy. That 1/2-3/4 of ice is pretty close. This honestly has ice storm written all over it IMO. Anyone have an idea of current ground temps or could someone post a map? They have to be in the mid 20’s I would think. A road temp map would be great too. The one positive with this one is that they have heavily treated the roads with deicer. That and the dry air will initially be stubborn to overcome. Oh also we will get above freezing before crashing back down lol. The negatives are it’s already cold, no-one has cancelled school tomorrow, it’s during rush hour, and I think it will be below freezing for quite a bit of the daylight hours when the sun angle is highest. I’m going to charge electronics up tonight, just to be on the safe side…

  • Drew Blasi says:

    As a 16 year old in high school it is horrible waiting tell the morning to make the call on school closings. That being said I understand why they do it sometimes really hoping they just call it tonight so I don’t have to do my homework.

  • Blue Flash says:

    Independence Schools have cancelled already. This place comes to a screeching halt with freezing fog or drizzle. How are we going to handle an inch of ice on thoroughly chilled roads? (Gerard’s graphic shows 1/2″ to 1″ of ice accumulation on the roads by 7 am.) 33 degrees in the afternoon won’t melt that off!

  • Adam Taylor says:

    Can you watch a Facebook live event without having a Facebook account? Zucherberg’s social media ad machine isn’t my cup of tea

  • michele springs says:

    Hows St Joe looking? Snow or freezing rain?

  • Josh Honas says:

    Yeah, I am glad I made that comment because now it seems like some schools are taking what the local meteorologists have been saying to light and cancelling classes for tomorrow.

  • Matt Galvin says:

    Shawnee Mission closed.

  • CJ Mac says:

    Facebook live on KSHB 41 page?

  • Austin Braddock says:

    What’s the fb live link

  • JeffG says:

    When you start your facebook live can you post the link?

    Thanks

  • Steve Huff says:

    Facebook live still to come, or did I miss it?

  • Zach Kumke says:

    SLEET storm, little snow, less than .2 inch of freezing rain. Just like the Dr. ordered.

    You know if I actually did the trading on here, I could make a little money. Maybe with the next check

  • Jennifer Hill says:

    I live in Easton, MO but work in Lenexa, KS. Would normally leave at 730 in the morning
    Do you think I will make it. Debating on whether to call in tomorrow

  • Austin Braddock says:

    I’m left confused after the fb live

  • Rodney Davis says:

    Gary: Saw there is now a winter storm warning for Bates & Cass counties & NWS says this may need to be expanded eastward. How far eastward do you think warning could be expanded? Do you think it gets over into central MO?? Thanks

    Rodney (Ashland, MO)

  • Michael Batch says:

    LSR-7 sent an email at 7:04. School Closed!

    Hello, Lee’s Summit R-7 Families,

    There will be no school Friday, Jan. 17, due to inclement weather. We hope you stay safe and warm.

    Again, no school tomorrow due to winter weather.

    Be safe,

    Lee’s Summit R-7 Schools

  • Rock Doc says:

    All one needs to look at are the Skew-T charts to see the thickness or thiness of the warm nose of air and degree of saturation.

    This being said, the NWS needs to send up Sondes from downtown airport so Kansas City gets more accurate data and information. The closest Sondes are Topeka and Springfield which really doesn’t provide accurate data for Kansas City.

    What will really matter is the thickness of the warm air nose and saturation of this layer. Personally hoping for thinner layer which means more snow and sleet. Less ice means less potential for loss of electricity.

  • Rock Doc says:

    For people wondering about what I’m talking about, check out Joe Lauria’s blog on Fury channel internet site. Great writeup today on what happens with thin/thick saturated/unsaturated column of air. Cool diagrams too.

    Gary, you should consider posting similar diagrams and images for educational purposes. You can more easily point out what’s going on along with your thoughts.

  • Josh Honas says:

    Wow, this thing is throwing a curveball in the fact that the heaviest icing looks to be right south and west of KC, as opposed to south and east of KC. WSW’s right south of me here in south Olathe. Believe the south side of KC is going to take the brunt of this storm as far as ice, snow, and sleet go!

  • Eric Viera says:

    Long time reader, first time posting. Starting to get freezing drizzle coming down in Parkville, mixed with a little sleet. I never did get any snow. Was tempted to head in to work early, but I think I’ll just work from home instead.

  • Andy Bussard says:

    It’s all freezing rain since 4am in Raymore. No sleet.

  • MIkeOP says:

    Just drove from 143rd and Metcalf to 95th and Pflumm. No issues at all. Great job by the road crews.

  • Terry says:

    It’s barely been doing anything in Wyandotte County not hardly anything on the ground. Even went out and walked on the street in front of my house no problem

  • David Pollard says:

    From looking at my deck it appears 2 snowflakes fell and maybe 3 sleet pellets! LOL. All freezing rain for sure here in Blue Springs. Any chance of an arctic air watch coming soon Gary? I know you mentioned about that bottled up cold maybe making a run on us the last part of this month into early February. Is that AO heading into negative territory anytime soon?