Shane’s Winter 2022-2023 Outlook

BOWLING GREEN, Ky. (WBKO) - Alright, you’ve been waiting with bated breath, and now the wait is over! It’s mid- November, so it’s time for me to offer my annual look at the winter season just ahead.

Before I dive into this season’s forecast, let’s take a quick look back at LAST season, along with a few of last winter’s highlights. It was a WILD season that featured a couple of sizable snowfalls along with a couple of BIG severe weather outbreaks...one of which was historic and catastrophic.

Key predictions and outcomes for LAST season:

*Predicted overall precip: Above normal

*Actual precip for the season as a whole: Above normal (note: December rainfall was actually BELOW normal, despite how warm/stormy the month was). January and February featured above normal rainfall, though

*Predicted snowfall for the season as a whole: 7-12″

*Actual snowfall for Winter 2021-’22: 15.5″

* SEASON HIGHLIGHTS:

-- Warmest December all-time (avg temp for BG: 50.8°) with a high of 76 Christmas Day (also a record)

-- A blockbuster snowstorm that dumped just over 6″ of snow on Bowling Green Jan. 6th

-- A low of 1° with snowpack on the morning of Jan. 7th (subzero for many locations)

-- Near record warmth with severe storms and tornadoes New Year’s Day (high: 75°)

-- January and February featuring well above average precip. Ironically, December’s precip was BELOW average, even though it was so warm)

-- A “parting shot” of very cold air and 4-6″ of snow for many on Mar. 11th/12th

-- A rare, deadly outbreak of tornadoes that ripped through western and central KY. Three tornadoes touched down in Warren County, two of which struck Bowling Green directly. Part of the deadliest weather event in state history

Note: Our grand snowfall total for last winter included 5.1″ that fell on the evening of Mar. 11th into the early morning of Mar. 12th. That 7-12″ forecast snowfall was for the period Dec. 1st-Feb. 28th (meteorological winter). Take away that late-season snow in March, and the snowfall forecast was within forecast range.

I give my forecast for last season a grade of “B+”. The kind of warmth we experienced in December thru New Year’s Day was HIGHLY unusual, to say the least. But the rest of winter behaved more like winter.

That was last year. Now, let’s focus on THIS season.

Just for fun, here are the snowiest and least snowiest winters for Bowling Green (reliable snowfall records date back to the 1890s):

Now for the “players on the field” for the 2022-’23 season. (**This is the part where the conversation gets more “weatherese” (technical). If you want to see my forecast, scroll down to “Winter 2022-2023 Outlook”**)

1.) “TRIPLE DIP” LA NIÑA: Sea-surface temperatures near the equator in the Pacific Ocean can have huge implications on how winter seasons play out in Kentucky. Basically, if equatorial water temperatures in the Central Pacific are warmer-than-normal, then “El Nino” conditions are present. However, if those same waters are running cooler-than-normal, then we have a “La Niña”. That’s the setup yet again heading into this winter.

It’s rather unusual to have three consecutive La Niña years, but it’s not unheard of. Last year was a “double dip” La Niña , or what I referred to as a “Seinfeld La Niña”, If you’ve ever seen that episode where George Costanza gets called out for taking a chip, running it through a bowl of dip, taking a bite, then dipping that same chip into that same bowl of dip another time while at a gathering, you know exactly what I’m referring to here. Think of this season as “TRIPLE-dipping the chip”. By now, the guy who plays “Timmy” (the one who caught George double dipping) would REALLY be getting worked up! :)

La Niña winters often come in pairs. Such was the case in the Winter of 2016-’17 and 2017-’18. Winter ‘16-’17 was a dud - we had one of our mildest, least snowiest winters ever that season. But Winter 2017-’18 was colder and snowier overall. However, I had to go back awhile – all the way back to the end of the last millennium and the start of this one - to find the last time we had three La Niña seasons in a row. Winter 1998-’99, Winter ‘99-2000, and Winter 2000-’01 represent the last three consecutive winters with La Niña conditions. In short, Winter 1998-’99 featured a cold stretch with some snow in late December/early January, with a flip to record warmth accompanied by severe storms in late January. Winter ‘99-2000 was a dud, but the following season featured a VERY cold December with a number of light snow events (2000) before a pattern flip in January ‘01.

Like last year, this La Niña event won’t rank among the strongest we’ve ever experienced. It will be moderate at best going into winter before it’s forecast to diminish by February as Central Pacific waters temps warm back up a bit.

What does La Niña mean for South-Central KY?

Historically, it means two things:

1.) A very active subtropical jet stream (aka “Pineapple Express) with numerous storm systems running from near Hawaii all the way into the southern states and lower Ohio Valley. Such a setup usually results in wetter-than-normal winters for us. Of course, that wouldn’t necessarily be a bad thing right now, given the ongoing drought. In fact, long range indicators show a gradual end to our drought as we move toward winter.

2.) It also means we’re often the “monkey in the middle” between cold shots that try to swoop in with the northern branch of the jet stream (the polar jet) dips southward while a ridge of high pressure tries to build over the southeast U.S. This often places South-Central KY in the battle zone or the line between rain and snow with some systems. Heck, we saw this kind of setup just this past Saturday morning!

2.) PDO/AMO (Pacific Decadal Oscillation/Atlantic Multi-Decadal Oscillation)

The PDO refers to water temperatures in the North Pacific south of Alaska and off the coasts of western Canada and the U.S. Pacific Northwest. Based on recent trends, it appears the PDO will be in a somewhat colder phase this season given the mild sea-surface readings off the southern coast of Alaska. That hints toward quite a bit of variability in our temperatures. The AMO refers to the overall water temperature in the Atlantic. The AMO typically runs in 30 year cycles. Throughout much of the late 1950s, 60s, and 70s, the AMO was in a “cold phase”. Since the 1980s, however, the AMO has been in a “warm phase”.

3.) NAO/AO (North Atlantic Oscillation/Arctic Oscillation)

These pressure systems are the “wild cards” when it comes to winter forecasting. Unlike the indices mentioned above that deal more directly with sea surface temps, these refer to the movement (a.k.a. oscillations) of semi-permanent pressure systems in the North Atlantic and Arctic, respectively. Typically, a “positive” phase of the AO and NAO means warmer-than-average temperatures for our part of the world. When these indices go negative, however, it can result in blocking over or near Greenland. That blocking can force the polar jet to dive southward into the eastern part of the U.S., which in turn, dumps much colder air into Kentucky. There is some skill in predicting these indices up to about 15 days out. Beyond two weeks, though, that skill GREATLY decreases, hence the NAO/AO are truly the “wild cards”.

4.) OTHER MINOR FACTORS

It’s possible that solar cycles may have at least some impact on our winters. Some speculate that more solar flares/activity leads to milder conditions. Snow cover across polar regions and Canada leading into December may also have some bearing on temperature and storm tracks. After a dip in the sun spot cycle a couple of years ago, the number of sun spots appears to be on the uptick once again.

ANALOG YEARS:

Listed below are the winter seasons that featured patterns “similar” to the one shaping up this go round. I will stress, though, NO two winters are exactly alike! There are few other seasons with patterns that closely match up this year’s, but I narrowed my search down to the past couple of decades:

WINTER 2022-2023 OUTLOOK

Now that I’ve discussed this season’s players, it’s time to dive into my outlook. First for the annual disclaimer: THIS IS NOT AN OFFICIAL FIRST ALERT FORECAST! It’s simply my own take on how I think the upcoming season could play out.

My focus here is on the months that comprise “meteorological winter” (December, January, and February). For perspective, here are monthly averages for temperatures and snowfall based on 30 year climatology for Bowling Green. I should point out that a new set of climatological norms was released for our area earlier this year. It’s based on data from the period 1991-2020:

And now for the monthly forecasts:

TOTAL SNOWFALL FORECAST:

I think MOST of the snow we receive probably comes from two or three systems, with another couple of minor snow events possible. A reminder that when the National Weather Service issues a Winter Storm “Watch”, it means there’s potential for 4″+ of snow AND/OR a quarter inch of ice within a given time frame.

Some other projections for the upcoming season:

And one more thing…

SEASON’S COLDEST TEMP: 4 degrees in January

As I emphasize each year, there is always bust potential in these long-range outlooks. Even though the past two seasons panned out well for me in the snowfall department, the biggest bust potential lies in the snow forecast. If we stay mild through much of the winter, then we could wind up with less snow than forecast. But all it takes is one system tracking just right – normally across the Gulf coast states WITH arctic air already in place – to deliver a good thumping. The January 6, 2022 snow, where our region saw anywhere from 4-9″, was a good example. It’s worth noting, however, that MOST of Bowling Green’s snowiest seasons featured an El Niño pattern rather than a La Niña. The years 2015 and 2016 - the “snowpocalyse” years - come to mind. It’s highly unlikely this season will compare to those from the late 1970s or mid 2010s, but we’ve had La Niña seasons in the past that delivered quite a bit of snowfall. Winter 2010-’11 was one of those kind of seasons (over 21″ total). That one came up in my analog seasons listed above.

La Niña is known for roller-coaster temperatures in this part of the world. We’ll have PLENTY of ups-and-downs this upcoming season. Expect some warm spells, but expect some cold thrown in there for good measure, too. Transitions between those ups-and-downs can sometimes mean strong/severe thunderstorms. La Niña seasons are infamous for those kind of events. The odds of a repeat of the magnitude of last December’s tornado outbreak are slim, but know that severe storms can strike anytime of year for us and to always have a plan.

As always, no matter what Mother Nature throws at us this winter, the WBKO First Alert Weather Team will keep you updated on our changeable conditions, on air, online, and via our WBKO Weather app for your smartphone.

Now, let’s all see what this season holds. Thanks for reading! - Shane

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