KANSAS CITY, Mo. — A reminder that the winter forecast is coming up on Thursday as our thoughts will be revealed during the course of the day from the morning through the night. I bring that up again because last night’s GFS run was a snow lover’s dream come true: Several snowstorms targeting the region starting later next week, which for about seven days cranked out almost 2 feet of snow!

It was just eye candy though(!), and already the model has sort of backed off in the coverage of what was quite the rarity through the Plains. I’d post the snow maps, but as I mentioned in a late-night tweet (@fox4wx), it would just be trolling snow lovers. To be fair though, the EURO also has something cooking later next week as well, so the thoughts from the blog yesterday are still valid, just a few days after the time frame referenced.

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Kansas City Forecast:

Today: Variable clouds, more south and breaks north, chilly with highs in the mid-40s on the north side and a bit cooler on the south side.

Tonight: Fair skies and chilly with lows in the 30s.

Tomorrow: Any brief sunshine gives way to the clouds to the south moving up towards the north. Highs in the mid-to-upper 40s.

Thursday: Rainy and cool with highs in the mid-to-upper 40s.

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Discussion:

As we head towards the winter forecast, I don’t think I’m going to be able to get out a huge blog for you regarding it. I’m off on Wednesday (but I’ll be getting a winter verification of previous forecasts from the team out to you that was put together by Jacob). Some of those prior winter forecast blogs were almost 3,000 words long as we went through every detail step by step.

What I will do is get a recap blog out for you on Friday morning of the winter forecast and then perhaps add a few more things next week as well. It won’t be 3,000 words long though, which is probably a good thing for your eyes and my typing skills.

One of the things that we are looking at though is the continuation of La Niña. What is unusual is that this is the third continuous year of the phenomena, so let’s see if that has a correlation to what happens around these parts.

Let’s start with the basics though. Something that we’ve talked about in the past related to winter forecast thoughts is La Niña. In its most simplest form, La Niña is a cooling of the equatorial Pacific waters from near the coast of South America westwards for thousands of miles. The extent of that cooling equates to the “strength” of La Niña. More cooling, “stronger” La Niña. The less cooling, the “weaker” La Niña is.

So let’s show you this cooling as we start this off. Take a look towards the Equator in the Pacific Ocean. See that area in blue/green: that is La Niña. Cooler-than-average waters in the Pacific Ocean west of northwestern South America all the way towards the northeast of Australia.

La Niña is the opposite of El Niño. El Niño is a warming of roughly those same areas, and if the magnitude is strong enough, both features can help to alter the jet stream patterns in the northern hemisphere.

Goodness knows there are other things that we know about and things that we don’t know about that may affect the weather over the upcoming winter season. That pool of warmer-than-average waters across the northern Pacific Ocean near Alaska will do “something.” The warmer waters off the east coast are also sort of interesting as well. Plus other climate factors can influence what happens, but that is for another day.

So typically what can happen in La Niña is this frequently shown type of map for “general” weather conditions.

The idea is that there is an area of blocking high pressure towards Alaska and that has the tendency (not every day or every week) to create stronger northwest flow through the Plains with a more active sub-tropical jet stream in the deep south U.S. that promotes more precipitation and potentially more severe weather as well. Again this is a VERY general and broad sketch of potential impacts.

The direct correlations though for us locally are more “meh” than anything really. Some La Niñas give us more snow than average (18.2 inches), others less snow than average (sometimes a lot less snow), so it’s tough to connect La Niña to winter snow forecasting here in Kansas City.

As I started this blog though, I mentioned that this is going to be the third straight year of La Niña. This is very rare. Back-to-back La Niñas aren’t that unusual. Back-to-back-to-back La Niñas though are, so I wanted to dive into that aspect of things.

Previous three-year La Niñas were in 1954 to 1957; 1973 to 1976; and 1998 to 2001. That’s all we have to look back on.

So I thought I’d focus on the snow totals for the third year of La Niña in those periods.

For example, the winter of 1956-1957. That winter we had 13.7 inches of snow, about 5 inches below average.

How about the winter of 1975-76? 21.8 inches of snow.

Finally the winter of 2000-2001: 22.8 inches of snow.

So two out of the three winters were snowier than average. Interesting, but a very small database to work with.

As far as the temperatures go though, some interesting numbers, and potentially pretty darn cold. I extended this into March because there is a tendency for March La Niñas to be pretty miserable.

From Dec. 1 through March 31, 1956-57: Overall, sort of middle-of-the-road average temperature wise (34.8 degrees).

In 1975-76, the average temperature was 31.7 degrees, which was the 16th coldest.

And finally 2000-2001: 29.5 degrees, our sixth coldest.

So let’s break that data down even more, and go month by month. Three third-year La Niña winters, December through March.

You can see that typically when there is a third year La Niña, there is at least a month or so that really trends above average. Look at February of ’57 and February of ’76, and a thaw even in January of 2001.

So after all this as an exercise, was it worth it. Not too sure. There are so few times, only three, that we’ve had third-year La Niñas that it’s tough to make any correlations. As I’ve said for two months now, I still feel that this will be an above-average winter for snow through March. I also feel like the chance of a White Christmas is elevated this year. As you know, I’ve been banging on that drum for almost two months as well. I do feel like there should be some milder weeks in there as well with real winter thaw times too.

Tomorrow’s blog will get a big assist from Jacob.

Finally, the system this Thursday will be a nice rain maker for us as we continue to chip away at the drought. We’ve done pretty good over the last month or so regarding this situation, so I’m hopeful that as we enter the driest time of the year (climatologically), we can keep adding in on the moisture situation.

The feature photo comes from Chuck Carbajal.

Joe