Dec 18, 2010

Snowfall Predictions Using the LRC

I have decided to try my hand at creating a personal snowfall forecast this winter using the little knowledge I have of the LRC. After I began I asked myself why I was going through the trouble of researching and analyzing all this. I have several questions that need attention. For example, when will the next snow day occur at my wife's school? Or when can we take a short trip without having to find a substitute observer? Or will it snow next week when I drive to a customer site 60 miles away? Or when is the best time to play on the shores of Lake Superior and Lake Michigan? Questions like these need answers and it is all possible to obtain using the LRC. So I continued. I researched the length of the LRC (47ish days), precipitation totals, archived radar loops, and 500mb height contour maps. I created a spreadsheet of what I found listing the cycles and daily precipitation totals during each and highlighting when the chances of snowfall may take place in the area from now through January. The spreadsheet can be found here. To sum up the spreadsheet, it shows Dec 19-23 may have a low move in from the W bringing an inch. Dec 28-31 there could be a low that moves in from the SW where greater than two inches could fall. Jan 6-12 a series of disturbances could work through leaving three or more inches. Jan 15-18 another low moves in from the SW potentially leaving two or more inches snow. And then the big one, Jan 25-29, the return of the 'Great Lakes Cyclone' once again, the third iteration. It turns out these last dates coincide with the school and work week taking place on a Wednesday through Friday. A snow day to look forward to perhaps. Overall snow totals from now through January could be somewhere around 14 inches in my backyard. That amount would put OSNW3 over the two months of December and January average total snowfall for Oshkosh.

My confidence in the LRC is relatively high at this point in my recent following of the cycle. Jeremy Nelson and Mark Baden of WISN WeatherWatch 12 have kept the LRC talk in top priority. Jeremy's long range forecast can be found by following this link to the blog entry. "The great thing about the LRC is that anyone can follow along and try to make their own forecasts". We'll see if I should hang up the LRC crystal ball as the next cycle comes to a close. :)

(2010-11 OSNW3 LRC List)

(red fill is start/stop points in forecast, chances of snowfall are lt grn , grn , and drk grn)

Nov 9, 2010

Lezak's Recurring Cycle; A view from OSNW3

Lately I've been expressing my interest in the LRC and I've done a bit of digging for some personal verification of the theory. As it goes, I was informed by Jeremy Nelsen in a recent blog entry that the LRC length last year was around 60 days. Knowing the LRC is determined between Oct 1 and Nov 10, I started with the first pronounced storm system to work into the region. October 8, 2009 is where I chose to begin the cycle to see if the same storm recurred 60 days later. Indeed it did around Dec 7, 2009. Adding another 60 days from then the cycle recurs once more landing the storm system in the region around Feb 8, 2010. Again, the storm affects the region 60 days later around Apr 6, 2010. Analyzing the graph and radar loops linked below, each storm recurrence shares enough similarity to verify the 2009 60 day LRC in my opinion.

Oct 7-11, 2009
Dec 8-10, 2009
Feb 8-11, 2010
Apr 7-9, 2010


I needed another instance to verify. October 22, 2009 is where I chose to follow a second storm through the cycle. Each recurrence of this storm shared many of the similarities as did the above instance.

Oct 21-24, 2009
Dec 23-29, 2009
Feb 21-25, 2010
Apr 22-24, 2010


As of right now, I have one major interest in the upcoming LRC length. Just when will the "Great Lakes Cyclone" show it's face again? My anticipation for the 2010 LRC length is growing day to day, and as Jeremy Nelsen states in his most recent blog entry, the pattern is very close to being set! 36-38 days? That would bring a whopper of a winter storm to the region around Dec 2, 2010. We will wait and see!