Challenges of snow forecasting this week

 Hope you had a terrific Thanksgiving week. We are about to begin the month of December with a chance for some snow, HOWEVER, temperatures aren't going to be all that rough on us just yet. 

Snow forecast challenges ahead:

The hardest thing to do ahead of a winter system is pin down where the heaviest accumulations of snow will fall. Every storm presents its own unique challenges, and this one will be no different. The last 4 or 5 days, one model showed snow while another model had nothing at all. We are finally seeing some agreement that snow WILL setup in the Plains, but determining where the storm will wobble around is tough.

Here's what one model shows on accumulation for Wednesday/Thursday:

As you can see, it focuses more of the snow central and east. The amounts aren't huge, and at this time, I would doubt this storm would have anything record setting with it anyway. But what we want to take away from this is where the snow accumulations might be.

Another model has this:

Suggests that much of the snow will end up in southern Kansas and northern Oklahoma. Similarities between the two models are that the amounts of snow are up to about 5 inches but not much more. That is still a pretty good snow for the Plains and given the temperatures, would likely have some good moisture content to it. This is a storm where 10 inches of snow would equal about 1" of liquid precipitation. However, nobody is expected to come close to 10".

No Arctic air invasion! 

Don't like winter temperatures? This midweek system will have no Arctic connection. It does get cold enough to snow, but the air that will be in the Plains show no connection to the bitterly cold areas of Canada or the Northwest Territories. What does that mean? It should mean a quick rebound in afternoon highs at the end of the week. Just look at the map for Thursday afternoon. Areas north of Kansas will actually be a bit warmer, so we should warm and melt the snow quickly by Friday and the weekend.

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.

Weekend storm is coming & a preview to Thanksgiving travel

Just days away from another November storm that should bring rain to the Plains. We hear the requests daily for moisture and confidence is increasing this will be a statewide event. As we have said before, it will not be a drought ending rain, but helpful in whatever we get. At a glance, heaviest amounts should end up east of a line from Hays to Garden City, but even areas out near the Colorado line should get something. The rest of the week continues to be quite warm and will be leading up to the rain chance.

Timing: Not much rain expected at daybreak Saturday, but chances go up quickly into the afternoon. This is NOT a big storm for the Plains and the amount of cold air is severely lacking, so we aren't spending . 

Best chances: 5pm - 3a.m. Sunday

The rain will keep pushing east Saturday night. 

Forecast amounts:

Should be safe to set expectations around .50", but I am fairly certain amounts will go higher than that, especially over the eastern half of Kansas. This would be very helpful for next years wheat crop, along with diminishing the fire threat for a bit. 

Next week - Thanksgiving travel:

Considering the setup across the country for next week, I think the weather looks good (finally a WIN in 2020, right?) There should be some rain moving across the southeast US, and maybe some messy weather in the Pacific Northwest (rain and snow), but I don't think a big storm will setup next week. Much of the Plains will likely have sun and above normal temperatures once again. Most of us are probably limiting our travel, but getting around the immediate area won't be much of a challenge. 

Our winter forecast comes out Saturday night on the KWCH at 6:30pm. I will also have a write up here on the blog so you can read more about what our thoughts are for the season. Have a great day.

How warm can we get next week & for how long

We are busy working on our winter weather forecast and the 30 minute special that will air next Saturday (November 21st). Our winter forecast will also be detailed here on the blog too as soon as we finalize it.

The focus for next week is on a HUGE warming pattern that will setup across the Plains and deliver not just warmth, but potential record warmth. Lately, the warmth has overpowered just about everything else in our forecast (except for the wind of course). There may be several days where it doesn't feel like mid-November.

Here's what the setup looks like:

Record highs are not a slam dunk at this point, but we should have a chance by Wednesday/Thursday and maybe even Friday. A slight shift in the wind could keep us out of record territory, but for now, there's a strong chance we might make history.

Are things about to change?

Sometimes the first signs of bigger changes begin to show in the Arctic Oscillation. When it goes negative, there's a strong tendency to get some much colder air dropping south out of Canada. You can see where things are headed around Thanksgiving. At this time, I'm thinking we will be turning "cooler" during the holiday week, but not bitterly cold. We may end up with highs in the 50s on Thanksgiving Day. 

Early Thanksgiving thoughts:

Beyond that, we may be slipping into colder weather heading into early December. Let's see if future model runs continue to show this negative trend in the AO.

Have a great weekend.

Another system coming later this week

Rainfall amounts ending at 7a.m. Tuesday:

One system moves away from us today (Tuesday) and another one is on the horizon for the end of the week. This is a system coming straight from California and will likely bring some more rain to the Plains states by Friday. 

Unfortunately, it's a disorganized system, so unless something dramatically changes in the data, its probably NOT going to be a big rain maker (and it will be MUCH too warm for snow). When we say "disorganized", that means the energy associated with the system is spread over thousands of miles and tends to make it weaker overall. 

Our first week of November has been quite mild and overall, that's probably not going to change much in the next few weeks. We will have some chilly mornings, but afternoon highs should stay at or above normal leading right up to Thanksgiving week.

It is going to flip soon, but I'm thinking it may not come until right AFTER Thanksgiving. Just look at the outlook for Thanksgiving week - suggesting much of the Plains will have a temperature average of 4-7° (likely yielding highs in the 60s)

Atlantic hurricane season record:

The National Hurricane Center named another storm yesterday evening. Substropical storm "Theta" is about 1000 miles east of the Azores. You can see in the map below it's in the middle of nowhere, but it does set the record for most named storms in the Atlantic season. It beat 2005 (when there were 28 named storms that year - including Katrina), and we still have a few weeks to go in the overall season. I wouldn't be surprised if we have yet another system coming up through the Caribbean. It will get the name "Iota" if it does develop. Stay tuned. What a crazy year.

A stormy trend ahead

So many areas in Kansas are still in dire need of rain and we have reason to hope that Mother Nature may help us out soon. On the air, we have been showing a potential storm arriving early next week, which would fit in with our November outlook I posted last week.

The setup:

This storm should organize across the western US over the weekend, resulting in STRONG wind gusts for the Plains Saturday and Sunday. Just look at some of the gusts Saturday and again Sunday.

 

 

I am expecting this western storm to break into two different parts, with the first part racing north into the northern Plains by Sunday evening. This leaves Kansas without any good rain chance through much of the weekend. However, where we start to run into questions (and maybe getting our hopes up for some rain) is the second piece that kicks out across the area on Monday and Tuesday. 

 

That's the part of the storm that may help to increase rain chances (and perhaps snow for western Kansas) at the beginning of next week. 

 

Confidence is still low on how this storm will play out, so I hesitate to put up any potential rainfall amounts yet, but there's a chance areas that were missed in the last go around may get a shot at some rain early in the week. It hasn't been looking all that promising for northwest Kansas to get some soaking moisture, but it is still early and so much can change yet.

Even if we don't get much rain, we WILL be much cooler early next week throughout the Plains and the Rockies.

If the storm doesn't do what we need it to do, there could be other chances looming.

I'm looking at another system that could swing through the Plains at the end of next week. It's strength and potential is unknown, but it's part of a pattern that looks very busy leading up to Thanksgiving week. You can see the brighter colors off the west coast. That indicates very strong upper level winds (the jet stream) and with it pointing into the southwest US, we may see more storm systems approaching that MIGHT help to bring some rain. Let's see how this plays out, but we do expect things to be more interesting in the weeks ahead.