Few Snowflakes Now…Weather Pattern Ahead

Thank you for stopping by the Weather Watch 12 blog! Make sure to bookmark this page and share it with your friends and family. I will strive to not only talk about current weather conditions, but also teach you about about a weather pattern theory that I think you will find very fascinating!  I introduced this theory a couple of days ago, and will expand upon it in this blog.

First, let’s talk about what is ahead for the weekend!  Overall the weather should be pretty tame.  Southeast Wisconsin is going to be just on the edge of the huge East Coast storm that may bring some locations 1-2′ of snow in the next 2 days!  Around here though outside of flurries or snow showers I don’t see any organized snows that will total more than say a dusting to half inch this weekend. 

Our wind direction is favorable for lake-effect snow right now, but temperatures just are not cold enough to get the lake-effect machine cranking.  So we will settle for the flurries or snow showers not only tonight, but into Saturday.  A little clipper system could still bring us a little light snow on Sunday, but again the 1-2″ snows will stays in central and northern Wisconsin.  Temperatures will be very seasonal in the upper 20s to mid 30s across the region.  Sunday may be the slightly cooler day.  The theme of our weekend forecast is no big storms!

That can’t be said for the East Coast as I mentioned above.  They will be hit with either a lot of rain or snow depending on the location.  Many are surprised by this storm, but could we have seen this coming?  I say yes, to a certain degree.  If you haven’t been following the blog I introduced a weather pattern theory called the LRC a couple of days ago.  This theory states the weather pattern sets up in October to early November and then begins to cycle.  Each year the pattern is unique.  This is the second time through the cycle and we have identified that the cycle length is about 60 days give or take a day or two on either side.

Before we look at a 500mb(middle of the atmosphere) map for this weekend’s big East Coast storm, let’s look back roughly 60 days to October 18.  The map below is an archive of the 500mb map from October 18.  This shows an upper level low over Virginia, a ridge in the Southwest, and another low nearing the Pacific Northwest.  The low over the East is really the dominate feature on this map.

Now let’s fast forward to right now.  The latest run of the GFS computer model shows nearly the exact same map forecasted for tomorrow, December 19, roughly 60 days from the map above.  The upper low over Virginia, the ridge in the Southwest, and the low approaching the Pacific Northwest are all almost identical! 

Certainly two maps don’t prove a theory, but I have been watching this same thing happen every year and am really amazed that the weather could possibly cycle almost like clockwork!

So what is in our future for Christmas week?  If you look back to that blog where I introduced the LRC, I also mentioned a large storm during the week of Christmas that could impact Milwaukee.  So what did this look like the last time around?  The easiest way to view the LRC is using the 500mb maps, but let’s just head down to where we live and look at a surface map from October 23…roughly 60 days before Christmas Eve.

The map below shows a very strong surface low just south of our area.  This storm produced over 2.00″ of rain in Milwaukee. 

So do I expect a big storm in the nation’s mid-section on December 23 or 24…yes!  The long range computer models that we use have been all over the place with this potential storm.  But Weather Watch 12 has been consistent in saying that a storm is possible around December 23/24.  I think our odds are much better of getting hit by the storm than it missing our area to the south.  Keep in mind the theory is used to help predict the tracks of storms using long range ride and trough positions, not how much moisture will be available, exact surface temperatures, ect.  So predicting snow totals a week out or more isn’t feasible…in my opinion since so many smaller scale factors are in play. 

This blog is meant for everyone, so I don’t want to get too scientific.  There is research being done on this theory and if you have questions please feel free to ask since this is an interactive blog.

Before we wrap up our discussion for now, I want to share a comment from the Assistant State Climotalogist Ed Hopkins…who I greatly respect!  Ed’s comments were in an article in the State Journal today.

Assistant State Climatologist Ed Hopkins, meanwhile, said meteorologists working on long-range forecasts are having difficulty explaining what’s going on.

“A fair amount of the country was experiencing cold conditions, when in an El Nino event it should be fairly warm,” Hopkins said. “I don’t have really any great explanation as to why this occurs.”

Here is the link to the entire article…

http://host.madison.com/wsj/news/local/article_3f5af4c4-1215-5db1-810e-1e840ba52791.html

In my opinion there is something greater going on in the atmosphere and not everything weather related can be attributed to El Nino or La Nina.

Have a great weekend and make sure to watch WISN 12 News at 5, 6, & 10 p.m.!

Jeremy Nelson

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2 Responses

  1. Giving all of us plenty to think about. Well written. Looking forward to how next week plays out.

    Mark Baden

  2. Jeremy – perhaps this snippet of the CPC 30 day outlook prog discussion dated Nov 30th can provide of clarity to the confusion in the current pattern…

    “…BELOW NORMAL TEMPERATURES
    THROUGHOUT MUCH OF THE CENTRAL AND EASTERN PORTIONS OF THE CONUS. THIS IS
    EXPECTED TO OVERWHELM THE USUAL ENSO TEMPERATURE TELECONNECTION PATTERN FAVORED
    IN THE EARLY PART OF AN EL NINO WINTER, AND THEREFORE THE TEMPERATURE OUTLOOK
    IS SUBSTANTIALLY ALTERED FROM THE OUTLOOK ISSUED IN MID-NOVEMBER. ABOVE NORMAL
    PRECIPITATION AMOUNTS ARE EXPECTED IN THE EARLY PART OF DECEMBER FOR MOST OF
    THE SOUTHEASTERN CONUS, INCREASING THE CONFIDENCE FOR ELEVATED CHANCES OF ABOVE
    MEDIAN PRECIPITATION FROM THE EARLIER OUTLOOK BASED WHICH WAS BASED ONLY ON EL
    NINO TELECONNECTION. ”

    Long story short, the last line is the most critical in explaining how everyone is confused. Only using one climate factor will make any long range forecasting difficult. Especially one based on ENSO. Yes – there are trends, but just that..trends. In trending long range, anomalies are generally smoothed out and lost in the analysis of the entire picture. This is where pattern analysis can be quite useful.

    There are two graphics that should have clued in folks to what is happening now. First is a blocking graphic produced by the CPC.

    Notice the blocking at 0 long and 140W around Oct. 16th. These high pressure features teleconnected in October contributing to a significant drop in the AO causing the northern jet to drop further into the CONUS due to the polar vortex being pushed down by the teleconnected ridging. The 140W ridge should look very familiar.

    What is happening again on cue? Look at Dec 16th. Same thing – and same AO response. 60 days apart. It will be interesting to review the height anomalies for December. It should be pretty similar to October.

    The second is pretty self evident. It is the AO trend for the last 90 days and what is currently forecasted.

    The whole month of October, the AO was negative. So will be December. This is no surprise. Should we be wondering about a late April freeze for those a bit further south? Something to think about…

    The LRC is not just seen by 500mb map comparisons, but can be viewed in other climate data such as teleconnection trends and MJO Phase Space Analysis.

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