Blustery Saturday & Potential Storm Next Week

***Watch WISN 12 News for the latest weather information!***

Thank you for stopping by the Weather Watch 12 blog!  Forecasting the weather anytime of year can be challenging, but my vote for the most difficult months to forecast the weather would go to either March, November, or December.  These months can bring temperatures either side of freezing to the area.  And this means the task of determining precipitation type, and where the rain-snow line will be located.

This challenge will once again present itself this week as another potentially wet looking storm heads our way.

Speaking of wet, most areas of southeast Wisconsin picked up rain on Friday.  The final totals will come in early Saturday, but here are the early totals as of 7pm Friday.  If you ever have a rain or snow total to share please post it to the comments section of the blog!

  • Kenosha  0.47″
  • Milwaukee Mitchell Airport  0.36″
  • Sheboygan  0.20″

 

On Saturday, a few snow showers and flurries will be around, especially in the morning.  Otherwise, a gusty north wind will put a chill in the air and keep temperatures in the low to mid 30s, but wind chills will be stuck mainly in the 20s.

One way to view forecast wind speeds is to look at various models.  Below is the RPM forecast map at 2pm Saturday.  This shows wind barbs(black symbols) with the one near Milwaukee showing a speed of 15 knots…or about 17 mph. 

RPM Saturday Winds

Keep in mind that one knot equals 1.15mph.  Now what do the winb barbs mean and how do you read them?  Here is a chart to help you out.  This map is from the US Forest Service.

Wind Barb Explainer

The next time you look at a surface map and wind barbs are used, you should now have a better understanding of what they mean.

Before we wrap up this blog, I want to touch on a wetter looking storm for the middle of this week.  This part of the pattern produced rain(0.40″) back in late November and snow in mid-January(4.9″).  And again this time through the pattern I am expecting precipitation in southeast Wisconsin.

Below is the 500mb(middle of the atmosphere) forecast map for Wednesday.  This forecast map is from the 18Z GFS.  What we are watching closely is the vorticity maximum over the Midwest, labeled with an ‘X’.  Also, if you want to check out how fast the wind is blowing at 5000 meters above the ground look at the wind barbs and then use the chart above! 

500mb GFS March 9, 2011

The location of the vort max helps in determining where the heavier snow may fall.  Lots of time between now and Wednesday, but this is a storm that I believe will bring rain and snow to the area, just how much of each is the question right now.

Make sure to watch WISN 12 News for the updates!  And post your thoughts, questions, and rain/snow totals to the comments section of the blog.

Have a great weekend!

Jeremy Nelson

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20 Responses

  1. Jeremy,

    I just posted a rainfall update in yesterday’s blog. Due to the timing of your entries, I wasn’t sure whether it should have been there are here. Just wanted you to know I got some info on it’s way to you.

    Cordially,
    Tony (Pl. Prairie)

    • Tony,

      Got it. Thanks! Plan on showing the totals at some point in the hour long 10.

      Jeremy

      • Jeremy,

        Fine. From now on, I’ll post whatever update I might be sending to the most current blog entry.

        Tony

  2. Hey Jeremy! Thanks for explaining what wind barbs are… I always wondered what they were exactly.

    Looking forward to seeing how next week’s storm plays out, and what kind of precip we get the most of!

    Have a great night,
    Dan

    • Dan,

      The wind barb graphic was kind of cool. Didnt expect that on the Forestry site. I always try to put things in simple terms in case a reader is new to the blog or I may have skipped an explanation in the past.

      Jeremy

  3. Jeremy, Mark, and everyone else… I thought you might be interested in viewing a time-lapse video of this past meteorological winter of my backyard. The file is 7MB and it can be viewed by clicking the link below. Is there a visible pattern within the video? 😉

    • That’s awesome, Josh!

    • Thanks for sharing Josh! Jeremy

    • Josh, very cool… thanks for the share! Looks like you’ve had at least a little snow on the ground every single day since the first snow 😀

    • Thanks for checking it out guys! There are many things I dig about the time-lapse, but one thing that stands out to me is the angle of the sun. If you watch for the shadow of the top of the fence you’ll notice how it moves towards the fence signaling a more direct sunlight as we move into spring…

  4. Hi, Jeremy —

    The latest from here in Reeseville, Dodge County is that we did get some very might snow from about 9:30 last night until around 2 a.m. today. Just trace accumulation. I’m thnking that with the snow or just before, we must have had a period of “mix” because there is a very light coating of “crunchy stuff” under the snow — not exactly ice, but now all snow either. Maybe “crunch” + snow is “crow”? 🙂 Salt is doing a good job melting it off. Temp as of 9 a.m. is 28 and it’s very windy. A few patches of blue sky now and then as well.

    Thanks for the opportunity to be a weather watcher with you.

    Don

  5. Saturday, March 5, 2011 9:13 am

    Hi Jeremy,

    No doubt you’re anxious to hear what the weather did overnight down here in the ‘Prairie’. Ok, maybe not, but I’ll tell you anyway.
    Left my rain gauge out all night. Got it in the house and ‘defrosted’ it around 8:30am. Looks like I picked up another ‘tenth’ of an inch. Grassy areas are ‘almost’ snow covered. Paved areas such as my driveway are clear & wet. Got pretty heavy overcast, fairly constant winds of aprox 10-15mph, primarily from the north.
    Appreciate having the opportunity to participate in the WW 12 Blog.

    Hope you have a good one!
    Tony (Pl. Prairie)

    • Tony & Don,

      Thanks for the reports…they help a lot!

      Jeremy

  6. Jeremy, have you seen the precip amounts for this week’s storm on the GFS? This thing is looking like a monster!!!

    • Dan,

      It does look wet! Previous two times through the cycle it produced about 0.40″ for MKE. Certainly a good sign there should be moisture to work with. 18Z NAM is farther north with the storm versus the 12Z GFS. In house RPM sort of in-between.

      Jeremy

      • So more rain than snow as of now? When looking at the red and blue lines on the GFS, what is in between the two? Is it rain, or a mix, or something else?

      • Dan,

        I’m not getting too specific yet outside of saying all of the above possible with the storm. In the March forecast I believe I said all types of precip or something like that. This is the prelude to the ‘signature’ storm. Now just over 2 weeks out from the main event!

        Jeremy

      • Cool, thanks Jeremy. But I was wondering in general, how to properly read the GFS and NAM. Where is the cutoff when looking at the red and blue lines on the models? A lot of times the gap between the two lines is quite large, so I don’t know if in that area, it is rain or snow?

      • Dan,

        A couple of general rules of thumb. You can looks at the 540mb thickness line and also the 850mb 0C line. Both of those can be used as a good starting point for the rain/snow line.

        Jeremy

      • That helps… thanks, Jeremy!!

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