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Thank you for stopping by the Weather Watch 12 blog. Today we are going to look ahead to the timeframe of February 21 to around March 3. This 11 day stretch should bring a very active weather pattern to the central U.S., and in turn bring above average precipitation to Southeast Wisconsin during this week and a half stretch.
Back on January 26 I made a long range forecast for the entire month of February. Highlighted within that forecast I said the biggest snow of the month would occur on February 8-9. On those two days Milwaukee picked up 8.8″ of snow, with some spots topping out at a foot of snow!
In that same forecast I highlighted the last week of February as one that should bring another active period of weather to the region. Several storm systems will form during this timeframe and likely continue into the early part of March. I don’t think our immediate area will take a direct hit each time the storms pass by, but one of the potentially 3 storms should bring a heavier amount of precipitation.
If you are curious how the long range forecast for February was made that is a great question. I use a long range weather pattern theory called the LRC…Lezak’s Recurring Cycle.
I have been very excited to introduce this theory to viewers here in Southeast Wisconsin. I first learned about the theory 4 years ago while working in Kansas City. Here is what the theory states:
- 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 winter-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.
To put this in very simple terms, the weather pattern that occurs in October and November repeats thru the Winter, Spring, and into the Summer. The cycle length will vary each year. Determining the cycle length each Fall really holds the key in using the LRC to forecast into the future. A very good idea of the cycle length is usually determined anywhere from late November thru December. Once the pattern goes thru its second cycle a period of days can be placed on the cycle length. As I have mentioned in previous blog entries, the cycle length this year is about 60-62 days.
Here is why I am confident in the forecast based on the theory above. Below is a 500mb archived map from December 22, 2009. I labeled the features that stand out 1-5. The upper level low labeled #5 dropped into the Southwest back in December and eventually curved northeast and brought our area a very wet period for about 2 days. Will this same weather pattern repeat?
Let’s jump ahead roughly 60-62 days to the forecast for February 22-23. Below is a 500mb FORECAST map from the 12 GFS. This map again is labeled 1-5 highlighting the larger features. If you compare the map above to the forecast map below…our main features are in virtually identical spots!
To me this adds to my confidence of a storm developing during the last week of February. The last 2 times through the cycle this storm brought a quick push of mild air followed by cooler temperatures. It will be interesting to see the setup this time around, but anything from rain to sleet to snow is possible.
On the heels of this storm…March will likely begin with more active weather and another storm in the nation’s mid-section. I’ll talk more about this potential storm in the coming days, but overall the timeframe from February 21 to March 3 should be very active and could bring Southeast Wisconsin many chances for precipitation. Also, the first week to 10 days of March overall should have below average tempeatures…especially in the northern Plains and upper Midwest. Remember those areas saw a brutally cold start to January.
If you have thoughts or questions about the weathern pattern please leave them in the comments section of this blog. Have a great day and thank you for stoping by the Weather Watch 12 blog and watching WISN 12 News!