LRC Suggesting Storm by the 25th

I haven’t written about the LRC (Lezak’s Re-occurring Cycle) in a while, so I will address it here a little bit.  The LRC, established by Gary Lezak at KSHB in Kansas City, MO, is a theory stating that a unique weather pattern sets up every year between October 1st and November 10th.  The cycle typically falls apart by late summer. The longterm longwave troughs and ridges that setup every fall are different.  A cycle length is usually established by the beginning of the winter, depending upon the unique pattern that sets up, which is identified at the 500 mb level.  This year, Lezak has identified a cycle somewhere between 58-66 days.  Therefore, this year’s cycle is approximately 62 days long, give or take a few days.  Based on this idea, we would expect our next storm system to arrive around the 25th of January, 62 days after the storm that moved through the area on November 24th.  Here is a look at what things looked like with the November 24th storm at 500 mb:

(Click to Enlarge)

We would expect a similar setup with this storm. Keep in mind, however, that it is possible that this storm sets up slightly further south, given the fact that we are in January with an upper-level jet that is typically stronger and further south. In November, this storm produced rain, as cold air was limited.  In January, we would expect either snow, or perhaps freezing rain (given the extensive snowpack and frozen ground).  I would be leaning more towards the snowy solution with polar air more readily available.  We will see, but it does appear that a storm will move into the area around the 25th, if you believe the LRC.  February also appears to be very snowy, bringing snowfall totals close to if not beyond record territory for Omaha.

On a different subject, thanks for all those who are viewing the blog. We have had 1739 views since the blog started last year, 1077 of them occurring in the past 3.5 months.  It really seems to be catching on this year, which is great news! Hopefully we can keep this going in the future!

Have a good weekend!

Ross

Winter Storm Verification

This blog entry is written to show the following: Old school techniques are NOT outdated.  Using Gene Weber’s rule of the heaviest snow falling along and to the left of the 500mb height fall center track, 4″+ was forecasted for the Omaha metro. The rest of the snowfall forecast made below was a result of using the Garcia Method, where the snowfall amounts relate to the mixing ratios that are found on theta surfaces.  Using these 2 techniques, with some but not total reliance on model forecasted qpf, the following forecast was produced:

It is important to note that while model GFS qpf indicated a wide area of 2-6″  across the entire midwest with no concentrated area of 4″+ a few days before the storm, the forecasted HFC track indicated that a concentrated area of 4″+ would be located very close to the above forecast.  Thus, it is stressed that model qpf should NOT be soley relied upon for snowfall forecasts.  Other techniques should be used.  The forecast is only as good as the time and effort put in by the forecaster.  Here are actual snow totals:

The forecasted HFC track almost exactly showed where the 4″ cutoff would be.  And now a look at Iowa’s snow totals:

While model qpf suggested that heavy snow would extend into northeastern Iowa, the Garcia Method suggested that the 4″ cutoff would occur as forecasted.  This proves the value of this method.

There were some 2″ amounts in western Iowa, which was surprising.  This was not forecasted, but these amounts were also not consistent with the 4-7″ surrounding them.  This made these amounts hard to forecast. Some 8″ amounts were also reported over northwestern Iowa, which should have also been accounted for in the forecast.

Overall, however, I think that the forecast worked out very well.  Models did not do that bad about a day before the storm, but they could have definitely been approved upon by using various techniques.

Ross

Snowfall Tapering Off — Phase II on the Way

With between 3 and 4 inches of snow on the ground at 1:00 PM, I’m not expecting much more than an additional inch of accumulation through the rest of today and into this evening. This places Ross’s forecast of 4 to 5 inches right on the money.

As the snow ends, the second phase of this winter storm will take over as winds increase significantly later today and tonight. At 1:00 PM, winds were southeast at 3 mph at Eppley, northwest at 22 mph at Columbus, and northwest at 35 mph, gusting to 40 mph, at O’Neill. This is what we’ll be dealing with later this afternoon, tonight, and on Thursday. Several inches of powdery snow are on the ground now, so the winds will create a lot of blowing and drifting snow, and potential white out conditions in open areas.

Wind chills are the other big concern through the end of the week. Lows should bottom out in the teens below zero on Thursday Night and at around 20 below zero on Friday Night. Highs on Thursday and Friday will probably not exceed zero degrees. The gusty winds will produce wind chills as cold as 35 degrees below zero, especially Thursday Night and Friday Morning. Winds will die down on Friday Night, but it still won’t take much to produce wind chills of 30 degrees below zero again. Some moderation in temperatures should finally occur toward Sunday.

Willy

4-5″ of Snow Likely For Omaha Tue Night Through Wednesday Evening

We are looking at 4-5″ in the metro out of this system.. Snow will begin after midnight Tuesday night lasting till about 6 p.m. Wednesday.  The heaviest snowfall will be to the left of the 500mb HFC track.. This will produce a 4-6″ band from Sioux City southeastward towards Ottumwa, Iowa.. 2-4″ will surround this band, with 3-4″ in Lincoln. Keep posted!

Ross