Memorial Day…A Warm-Up 7 Months In The Making

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Thank you for stopping by the Weather Watch 12 blog.  In today’s blog we are going to focus our attention on the hot weather expected for Memorial Day.  The first 90 degree high of the season in Milwaukee isn’t out of the question on Monday, and this possibility was forecast a month ago…no seriously it was!

If you follow the blog, you know we use a weather pattern theory called the LRC, or Lezak’s Recurring Cycle to make accurate long range weather forecasts.  Here is part of the May-July long range forecast that was posted here in the blog back on April 30.


‘In looking at the overall pattern I think the hottest temperature in Milwaukee will be 93 degrees.  That would likely occur with one of the bigger features in the pattern.  With that said I think the first chance at 90 degrees would come around May 30-31.  Then, if the pattern holds together another run to possibly the warmest temperature of the summer around July 19.’


But did you know the part of the weather pattern that will produce the hot temperatures on Monday has occurred four times already?  The basics of the theory that allows us to make long range forecasts are highlighted below.

  • A unique weather pattern sets up every year between October 1st and November 10th
  • The weather pattern cycles, repeats, and continues through winter, spring and into summer. Identifying the cycle length helps tremendously when making long range weather predictions.
  • Long term long-wave troughs and ridges become established and also repeat at regular times within the cycle. These dominant repeating features are a clue to where storm systems will reach peak strength, and where they will be their weakest.
  • The LRC is a season long pattern! There is a pattern! It isn’t just one long-wave trough, storm system, or ridge. It is a sequence of troughs and ridges that are cycling across the Northern Hemisphere.

Let’s take a look at past parts of the pattern, and how using them led to the hot Memorial Day forecast a month in advance.  The first time this feature revealed itself was during the second week of November.  On November 11 the high temperature in Milwaukee was 65…17 degrees above average.  Here is the 500mb(middle of the atmosphere) map from that day.

500mb November 11, 2010

The key feature is the strong southwest flow aloft over Wisconsin, and the trough in the Rockies.  These features would begin to repeat roughly every 50 days, the length of this LRC season’s cycle duration.

The second time through the cycle it was the holiday season.  But this part of the pattern warmed us up just in time to ring in 2011.  On December 31 the high temperature in Milwaukee was 54…25 degrees above average.  The same strong Rockies trough and southwest flow in the Midwest returned.  Here is the 500mb map from December 31.

500mb December 31, 2010

Roughly 50 days after this another big warm-up arrived in February.  50 days(or 1 cycle later) after that, southeast Wisconsin’s first taste of summer arrived as the pattern repeated again!  On April 10, highs soared into the 80s!  Milwaukee hit 84…32 degrees above average!

The trough in the Rockies and strong southwest flow returned.  Here is the 500mb map from April 10.

500mb April 10, 2011

It’s amazing how the features fall into the same general location each time through the cycle.  Once the April 10 warm-up occurred, I set my sights on the next time through the cycle.  It just so happens that 50 days after April 10 was Memorial Day.  So by using the LRC, I made sure to highlight May 30-31 as the potential first 90 degree high of the season in Milwaukee.  A high of 90 on Memorial day would be 19 degrees above average.

By using the LRC, and also shorter range models in the past week, you may have noticed that our forecast for Memorial Day has been much warmer than other forecasts…now you know why.

Let’s end by looking at the 500mb forecast map for this Monday from the GFS computer model.  The trough in the Rockies and strong southwest flow are present, and another big warm-up is likely! 

500mb GFS Monday, May 30

I’ve used the LRC for 5 years now, and while I expect the features to repeat, it still even amazes me!  If you would like to view the entire long range forecast that was posted here in the blog back on April 30, just click below.

Summer Forecast

If you have questions about the LRC or the weather pattern, just leave your thoughts and questions in the comments section of the blog.

In the meantime, make sure to check out WISN 12 News for the latest on rain chances for Sunday.  And if you want to track rain from your home or on the go, just click on the interactive radar link.

Interactive Radar

Have a happy and safe holiday weekend!

Jeremy Nelson


26 Responses

  1. On the news at 6, you made a small error. You said it was 88 degrees last Memorial Day on May 24th (which was true), but Memorial Day last year was on the 31st and the high was 77. Interestingly enough, Milwaukee hit 90 for the first time last year the day before that on May 30th. Perhaps that date can score two in a row.

    • Daniel,

      You are correct. I used the stats the NWS put out this afternoon for past Memorial Days. They corrected the date/high temp this evening. I should have double checked.


  2. Could I get a temperature forecast for Sheboygan for Monday-Tuesday? And will the warmth stick around?

    • Robert,

      I think on Sunday right along the lake in Sheboygan it will probably be 70s. Just inland a mile or more I think it would quickly get into the 80s.


  3. I have been reading that the Tornado weather may shift to the lakes in the coming week(s)..

    What is your take on that ??

    • Richard,

      Not sure where you saw that, but if you have a link pass it along and I will check it out. Then I can comment on what you are referring to. I highlighted some potential severe dates in the summer forecast. That link is included in today’s blog.


  4. Are the Lakes and Northeast Next for A Severe Weather Burst
    May 27 01:21 PM
    by Joe Bastardi

    The major cooling that is taking place in the mid and upper levels of the atmosphere is part of the change in the PDO from warm to cold over the past few years. It is not a coincidence that while tornadoes are grabbing headlines, record snows are blasting away in the western US. This is the 3rd time in the past 4 years where the elevation related snows are causing major snowpacks. The same thing happened in the early 50s. In addition, a look at the graph of strong to violent tornadoes shows an upward march as the cold PDO took over in the 50s, reaching a peak in the 70s, and then turning around and coming back down until the recent upswing began after the PDO turned cold once again in 2007.

    The conclusion of the graph is that strong to violent tornadoes increase when the PDO turns cold. I will take that a step further by matching that against the satellite data. Again, this is at the risk of not having the data before 1998 on the AMSU site, a fact which I am acknowledging. The last 3 great tornado months of May 2008 and April and May 2011 occurred after a major recorded drop from the previous year in mid tropospheric temperatures. The major drop in mid tropospheric temperatures was larger than the fall of the 2 meter temperatures. While one may dismiss that as coincidence… and I will allow you too, what it most certainly says is the WARMING was not the cause.

    In any case, the problem now may shift to the Lakes and Northeast. With a saturated ground to the southwest, higher than normal dewpoint air is liable to be available next week and the week after to come northeast. The ridge, will reach high tide over the next few days over the Lakes will back southwest, and by doing so, allow the Northeast and Lakes to enter a tornado producing pattern of major troughs from the west northwest attacking southeast into low level warm and humid air. This will become established later next week, and then try to return and develop in subsequent periods. This can be readily seen on the 500 mb ensembles.

    High tide, Monday:

    Next Friday:

    (thats quite a cool shot)

    Next trough starting southeast by Monday the 5th (its north of lake superior here):

    Interestingly enough, the super ensemble at day 8 (for late next week) had 3 of the 10 analogs from 1953, the year of the Worcester, MA tornado.

    That is not to say a tornado is coming to Worcester, Mass… it is to say that the next place to look for the threat of above normal severe weather is from the Northern Plains through the Lakes and into the mid and north Atlantic states later next week and the week after.

    • Richard,

      I’ll think about this and get back to you here on Sunday.


    • “While one may dismiss that as coincidence… ” I will indeed dismiss it. PDO like any other oscillation has global impacts – some more than others, but the atmosphere is a closed system.. meaning that any single oscillation will be hard pressed to be a singular culprit as other systems are involved as well. Joe cherry picked 2008 and this year, but somehow left out 2009 and 2010. 2009 was rather snoozy with below average tornadoes both in quantity and intensity. 2010 was about average. As far as his analysis for upcoming weather, I found it amusing to reference of moisture to the SW of the lakes….isn’t that quite normal in most years in the month of May? Anyway..enough ragging on Joe…I would think if you are looking for long range guidance, the LRC would serve one better.

  5. Even though the weather this spring has left much to be desired (the next few days excluded), I love watching how the LRC plays out, all one has to do is look at the maps from the last three times through the cycle and while the lows are always in a bit of a different position each time (seasonal variation), the overall pattern is unmistakable. Just imagine how much more accurate the NWS would be if they used this model.

    • Bryan – the world was flat for how long? 😉

  6. OK ,Thanks …
    That is from

  7. I think the LRC is amazing. It is not a coincidence that channel 12 meteorologists had a better batting average predicting storms and their severity this past winter.

    How long will this La Nina last? It has sure been a destructive pattern!

    • Mike,

      I don’t blame the deadly tornadoes on La Nina. If La Nina was SOLEY to blame as the cause, then wouldn’t every La Nina year produce mass amounts of destructive tornadoes? Just how I look at things. It may be an influence, but it is the pattern that is driving our weather. The same large scale features that produced features that resulted in severe weather have moved through in other parts of the pattern too. This is one way I made the severe wx forecasts that I included in the long range forecast. With that said, I would expect a pretty good tornado threat in the upper Midwest on Monday. Think back to April 10. Now that the jet is farther north, this threat is also shifting a bit more northwest of our area.

      And yes, I still think the LRC is amazing.


  8. Hi Jeremy!

    As always–thanks for the in-depth detailed work you do in teaching us and letting us know what’s up. The LRC is indeed quite amazing — seeing all those maps and the features repeating really turns LRC from theory to reality for me! There’s a certain comfort in knowing what’s up ahead–you can be so well-prepared!

    Can you define “trough” and “ridge” for me? From looking at the maps in this blog, am I right in thinking that “trough” is the ‘dip” over the Rockies and the “ridge” is the “upside down dip” in our area that brings the sw flow? {How about them hi tech terms I use? 🙂 }

    Thanks for answering.

    I hope you and your family have a great holiday weekend!

    Don {Reeseville}

    • Troughs smile and ridges frown… although the weather they bring tends to create the opposite expression on the faces of most of us.

      • Daniel,

        I’ll use that one at school talks from now on:)


      • Daniel and Jeremy–

        Thanks for the explanations. The smiles and frowns are language even I can understand!


    • Don,

      Troughs are areas of low pressure and ridges are areas of high pressure. With the LRC I look for long term longwave ridges and troughs. By knowing where these want to travel it makes long range forecasting much easier.

      Have a great weekend!


  9. So are you agreeing with what I have read about more tornado weather for the lakes could be coming ???

    • Rich,

      I can’t support or deny the claims of the PDO without doing my own research. However, in regards to the moisture, higher dew points typically come north this time of year. Yes the soils are saturated, but with a late corn crop and one that will not be maturing in the next few weeks, means the evapotranspiration will not be contributing to any higher than average dew points. Something that can spike dew points in the Midwest. So in regards to dew points I don’t see them much different than ‘normal’ years.

      It’s really all about the pattern. When we get into specific parts of the pattern the flow of moisture into certain parts of the country will be greater. Here are a couple dates I highlighted for severe weather in or close to our area in the May-July forecast. I just picked the 2 around where we are at now.

      •May 29-31 ‘Big warm-up’ storm
      •June 7-9 Storm from November 22, April 19

      Severe weather occurred today over Illinois and lower Michigan. Monday will produce severe storms over the upper Midwest, and we are in a slight risk for Tuesday. The ‘reload’ part of the pattern that Joe refers to I’m guessing is the start of the second week of June highlighted above. Many meteorologists have their own methods to forecast, and as you know I find the most success with the LRC.


      • Thank You for taking the time and research to answer my question…
        I guess we will have to see what happens….
        And how the LRC plays out..
        Thanks again..

  10. Sunday, May 29, 2011

    Rainfall report: As of 4:45pm, total rain 0.75 inches. In addition and not included in that total is a rainfall amount of 0.07 inches. Not exactly sure when that rain fell but I suspect it’s from Fri/Sat at some time. Whenever it fell, I ‘noticed’ it around 9am this morning when I checked to make sure the gauge was empty for today’s rain.

    Tony (Pl. Prairie)

  11. Thanks for all the hard work, Jeremy! Your accurateness is absolutely incredible, as well as your certainty and willingness to put it all on the table. 😀 Does predicting storm systems get a little tougher when it’s not the winter season? Are thunderstorms much more difficult to predict using the LRC because they can be hit or miss?

    • Dan,

      Thanks for the note. Using the LRC in June and July gets pretty tricky. The weaker flow aloft, and the LRC slowly fading all contribute to sometimes just the bigger features really sticking out. Just think, a stronger clipper system in the winter, may now just be a small shortwave that gets caught up in the flow and we barely notice it.

      The stronger features will still show up into July, so we can still have some fun using the LRC for a while.


  12. Jeremy- You clarified the “does La Nina cause destructive weather ?” question I had very well…

    Speaking of LRC in July, we are traveling on July 19. Wasn’t there going to be a significant event in the LRC those 2 days?

    Thanks for chatting with us! Mike

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