Winter Forecast 2020-21

I never know if you'll be excited when you read this or disappointed (maybe that's with every storm we discuss here), but we have released our winter forecast. This has been a record year for lack of tornados in Kansas, but in the Atlantic basin, a record number of hurricanes and tropical storms. A total of 30 named storms - almost made it halfway through the Greek alphabet.

So what does all of this mean for the winter? There are always several challenges when coming up with these predictions, but here are some things we are taking into consideration.

La Nina: 

Located in the Pacific, near the Equator, this is where the water temperatures are colder than average. This change in the water temperatures does have an influence on the patterns across the United States. Look at the latest image above - shows the colder water that has built up along the equator (as indicated in the blue and even purple colors) We know that La Nina summers are notoriously hot and dry for Kansas - so let's hope this weakens before summer 2021. Winters are more of a wildcard for the Plains. Some La Nina winters are quite cold, but others are near normal. Most recent La Nina winters (2017-18, 2010-11, 2011-12) had near to above normal snow and several cold outbreaks. That's strongly considered in this prediction. La Nina is forecast to stay through spring of 2021. 

What kind of weather pattern normally sets up in La Nina? Take a look:

It will remain strong enough to be a contributor to our weather patterns in the months ahead. Colder than normal weather is likely in the northern Plains, with expanding drought potential across the southern states. Wet weather is typical near the Great Lakes in a La Nina setup. 

Arctic Oscillation: 

During the month of October, it dipped into the negative, but then we saw it go positive in November (resulting in a milder month). It's not uncommon at all to see these wild swings, but when it dips negative, we should prepare for our big cold snaps. It's likely going to be near neutral into the first half of December, so it will be chilly, but not crazy cold. Where it might go negative is late January and February, so that would be when I'd expect the strongest Arctic outbreaks. 

Patterns: Given the La Nina influence, the jet stream winds will likely come down over the northern Rockies and right over the central Plains. That could mean a BIG temperature contrast from east to west. And if the jet shifts by a hundred miles or so, could be the difference between Arctic cold and somewhat milder weather.

However, I do expect a few decent storms to develop over the Rockies and then push into the Plains. We saw this in late October and most recently with the storm that dropped mainly rain (and a little bit of snow in central Kansas). Classic, major winter storms come in from the desert Southwest, but I think the storms this winter will form closer to Kansas. That will be something to watch as we continue on into winter. 

Summary: 

I think we should have near normal snowfall this winter around much of Kansas. I don't think the drought conditions are going to improve; that's very hard to do in the heart of winter. But maybe the drought won't get any worse if we get some decent snows periodically throughout winter. We've already had some icy weather (back before Halloween), and my concern is that may show up again this winter. If the jet stream stays in more of a northwesterly pattern, we might escape the threat. 

I'm also expecting some of our coldest weather to arrive in February this winter. There will be plenty of chilly days before that, but that might end up being our coldest month this winter. January may have some surprising warmth for the Plains.