Winter Weather Outlook 2014-2015

Hi folks! We’re into the final weeks of “meteorological Fall”, which runs from September 1st through November 30th. But Mother Nature has already delivered reminders that Winter will soon be upon us. Many of us saw our first snowflakes of the season on Halloween night. Remember last November? Bowling Green picked up an inch of snow three nights before Thanksgiving. We are indeed entering the time of year where ANYTHING goes with our weather. With that in mind, it’s time for me to make my annual predictions on the upcoming season.

Winter forecasting is mighty challenging! Each year brings us a different set of atmospheric setups resulting in variable patterns. Fluctuations in the two jet streams (the subtropical and polar) that steer our storms and control our weather during the cold season have EVERYTHING to do with what we see and what we don’t. Trying to predict exactly how the jet streams will behave and interact is not simple, especially two to three months down the pike. Heck, last season was proof that it’s tough enough just nailing down possible snow/ice accumulations only a few short hours prior to a winter storm’s arrival! But there are clues that provide us forecasters with some ideas on what kind of patterns will try to establish themselves and which pattern may be the most dominant over the course of a winter season.

Before I get into the discussion of this season’s “atmospheric players”, let’s check for a moment to see how I did overall with last Winter’s forecast. Let me first say this about last year: It was the TOUGHEST WINTER I have ever faced in my 14 years of forecasting at WBKO! It seemed Bowling Green was almost always on the rain/snow fence or was on the edge of a main snow band with practically each system that came through.

***LAST YEAR: 2012-2013 Forecast snowfall for the season – 7-10”. Actual seasonal total: 10.4”, although nearly half that amount came with the big snow/sleet storm (more sleet than snow) that hit on March 2nd/3rd.

2012-2013 Forecast temperatures (here’s where I really wound up with egg on my face!):

–Dec. 2013: (1-3 degrees above normal) Actual monthly average: 38.8 (close to normal)

–Jan. 2014: (0-2 degrees above normal) Actual monthly average: 29.4 (6 below normal)

–Feb. 2014: (1-3 degrees below normal) Actual monthly average: 35.2 (4 below normal)

That was last year. Now, let’s talk about this season and the factors that were given considerable weight when I comprised this outlook. Bear with me, as the talk gets technical at times, but I shall do my best to explain as I go.


Chances are you’ve probably heard about “El Nino” and “La Nina” since these two often steal the headlines. Basically, El Nino refers to an abnormal warming of the sea surface water in the Central Pacific ocean off the South American coast. When those same waters show cooling, it’s “La Nina” that is present. If the water temperature at the sea surface is right at or close to normal, neither El Nino nor La Nina is present. That’s what we call an “ENSO Neutral” condition. Such was the case last season.

 photo Shane_El-Nino-effects-in-the-USA_zpsb4b3e0db.jpg

*Imagery courtesy of NOAA

Early in the Summer, NOAA issued an El Nino Watch for the good possibility of significant warming in the central Pacific waters. Up to this point, however, that warming has been modest at best. So it’s clear we are NOT looking at a strong El Nino this season. The forecast indices continue to hint at what will likely be a weak El Nino this upcoming season. This DOES have a great deal of bearing on my forecast. Normally, strong El Ninos result in very mild winters with not a lot of snow for us. However, weak El Ninos tend to be much colder and snowier overall for Kentucky.

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. Heading into this season, the waters in these regions have displayed some warming. That’s important to this forecast because often when that warming occurs, we’ll see large ridges of high pressure become established over the Gulf of Alaska, which can often force very cold air to ride up and over and then down into the lower 48. The chart below shows a history of PDO cycles (note the cold PDO though much of the 1960s and ‘70s, many of those years featured harsh winters for South-Central KY):

 photo Figure_PDO-01_zpsc950a918.jpg

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”. Some of you may remember the brutal winters we endured during that stretch (1959-’60 and the last three seasons of the ‘70s). The AMO was also in a cold phase back in the 1910s, a decade that featured one of the Ohio Valley’s most severe winters (1917-’18). Since the 1980s, however, the AMO has been in a “warm phase”. It remains in that mode now. Many speculate this could be a major reason why many (though NOT all) recent winters have been relatively mild for our region.

 photo image004_zpscdfc973f.jpg

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. Those movements can be erratic, and it’s difficult — even for the most experienced meteorologists — to forecast them beyond two to three weeks out.

 photo Shane_NAO2_zpsc21e1fe8.jpg

There are two phases of both the AO and NAO. When each is in a negative phase, the polar jet tends to dip down into the eastern U.S., sometimes sending cold, arctic air into our region. By the same token, a positive phase of each of those indices generally means the eastern U.S. (including our region) is mild to warm. The AO/NAO fluctuated wildly at times last winter, often resulting in repeated shots of bitterly cold air. Long-range climate outlooks hint that high-latitude blocking may set up at times again this season, which could lead to extended stretches of very cold air. Again, one can only speculate.

 photo Arctic_Oscillation-01_zps97edac2c.jpg


There’s still lots of uncertainty on the role solar flares and their cycles play on winter weather. Some speculate that more solar flares/activity leads to milder conditions. Another factor to consider is snow cover across polar regions and Canada leading into November.

I don’t fly blindly when it comes to comprising seasonal forecasts. There really is a lot to consider. The variability of the AO and the NAO does not make forecasting any easier. But it helps to look back at previous winters to find those that saw atmospheric conditions and ocean temperatures similar to what is expected this go round. Those seasons are referred to as “analog” seasons. Here are the ones I found that seem to most closely resemble the kind of pattern I think shapes up this winter:






Notice most of those seasons I have listed show up here in this composite of temperature departures from normal (courtesy: NOAA)

 photo Modelnino_zps085ddfbe.jpg

If you like snow, you’ll be happy to know that many of the winters mentioned above were pretty generous in bringing the white stuff. The season that may raise a few eyebrows might be 1976-’77. That El Nino season featured some brutally cold weather (esp. in January ‘77) with many days of sub-zero cold and over 20” of snow! More recently, 2002-’03 gave Bowling Green around a foot of snow with 16” falling in ‘09-’10. I will say ‘76-’77 is the extreme/worse-case scenario in terms of cold – one that is HIGHLY unlikely to be duplicated this season. But remember…none of this is a guarantee!



With all that said, it’s time for me to cut to the chase to get into what I know you came here to read: The Winter Outlook. My focus will be on the three months that make up “meteorological winter” December, January, and February. I’ll add, too, that this is NOT an official First Alert Storm Team forecast! It’s simply my own take on how things may play out.

DECEMBER: This could be a tale of two halves. I think the November chill could carry over into the first half of this month, with a milder spell to finish it. Probably not what you want to hear if you’re hoping for a White Christmas, although we can never say never to that. In a way, this month could be shades of last December…one that started mighty cold before warmer temperatures won out for awhile late. I do think we’ll have at least a couple of shots for accumulating snow during this month.

DECEMBER TEMPERATURES: 1-2 degrees below normal (Avg. temp for the month is 38.6)


DECEMBER SNOWFALL: 1-2” (Above normal)

JANUARY: This is normally the coldest of the winter months, and overall, this one should be quite chilly! We should see the polar jet take more plunges southward this month with at least a couple of extended periods of cold. I don’t look for the entire month to be bitterly cold, though. Past history of years with patterns similar to this one indicate we will see some mild periods (January thaws) from time to time. January 2003 and January 2010 both had their fair share of very cold temps but we did see the cold relax for roughly a 10 day stretch in those months. Snow amounts will greatly depend on how the polar jet interacts with the subtropical jet. In previous weak El Nino winters, South-Central KY usually came close to, or was right in the middle of a major winter storm. A storm in late January 2010 brought 5.5” of snow to Bowling Green…the most from one system since March 1996. However, in January 2003, a similar system took a jog further south and nailed Nashville with 8” of the white stuff while Bowling Green wound up with only three inches. Another winter storm took a track almost like that one in January 1988 (another El Nino season) with parts of Tennessee getting more snow than South-Central KY. History could repeat itself if we see the southern-branch jet stick closer to the Gulf coast this season, but I think our area gets in on at least a couple of decent snows in January 2015.

JANUARY TEMPERATURES: 1-2 degrees below normal (avg. temp for the month is 35.7)


JANUARY SNOWFALL: 5-7” (Above normal)

FEBRUARY: This is often the toughest month to make a prediction as there is more uncertainty about how the patterns will behave this far out. So again, we must look at past history with our analog seasons. In most of those seasons, we had at least one significant snow event during February with one or two other minor events. Something else we may have to watch for this season is an enhanced risk for an icing episode. February 2003 brought a major ice storm to northern portions of the WBKO viewing area as well as Northern/North-Central KY. I believe February starts cold before some late-month warming takes place as Spring draws closer.

FEBRUARY TEMPS: 0-2 degrees below normal (avg. temp for the month: 39.8)


FEBRUARY SNOWFALL: 5-7” (Above normal)


When it all shakes out, here is the way I envision the season unfolding:

TEMPERATURES: Slightly below normal

PRECIPITATION: Slightly above normal

TOTAL SNOWFALL: (12-16” – 3-7” above normal)


CHANCES OF SEEING AT LEAST ONE SIGNIFICANT SEVERE WEATHER EVENT BETWEEN DEC. 1ST AND FEB. 28TH: 30% (lower chance than in La Nina winters but one or two severe episodes are possible)

SEASON’S COLDEST TEMPS: Between 0-5 degrees (should happen in January)

There you have it. Basically, when it’s all said and done, I think this season is snowier overall although probably not as “stretched out” with the snow events as last season, when the first occurred in November and the last in mid-April. In each of the weak El Nino seasons that served as analogs for this one, we did not see significant snowfall after February. That is not to say we won’t see accumulating snow in March (recall our biggest winter storm of last season happened Mar. 2nd/3rd), but I think it’s less likely this time. Once the cold breaks in these weak El Nino seasons, it’s usually “hello Spring” afterward. We shall see if this one follows suit!

I’ll be the first to admit THERE IS BUST POTENTIAL with any forecast, especially one that goes several months out! For example, if the subtropical jet stays suppressed to the south and/or the polar jet stays locked up into Canada more often than expected, than we could wind up with less snow than forecast. But I am leaning quite a bit on past history with weak El Nino seasons that featured similar sea surface temperatures and indices.

I’d like to know what YOU think. Do you agree or disagree with my outlook? Let me know either via my professional Facebook page, my twitter feed (@Main_Event_Wx) or via e-mail at Just keep the comments clean, please.

As always, be ready for no matter what the weather throws our way this winter season. Have a plan of safety should you ever need to use it. Whether an ice storm or a tornado, you should always be prepared. As we like to say around here “Know the weather before it knows you!”

Let the games begin.


Summer 2014 Forecast

“Sometimes I wonder what I’m gonna do but there ain’t no cure for the summertime blues.” – Eddie Cochran

That’s right.  Summer is now upon us, which means it’s time for another seasonal outlook.  Now I promise this will NOT be as lengthy a read as my Winter Outlook.  We don’t have near the number of factors or complexities that must be examined when making a winter forecast for our area. That being said, no two summers are exactly alike.  Take the past two, for instance.  2012 and 2013 were as different as night and day. 

First, I should clarify the months I am focusing on here.  Memorial Day weekend marks the “unofficial” start of the season, while June 21st is the first official day of Summer, according to the calendar.  My forecast will focus on the period that makes up “Meteorological Summer”, which is June 1 through August 31st. 

For sake of perspective, here are the AVERAGE temps/rainfall amounts for the next three months:

June: Temp: 75, Rainfall: 4.2″

July: Temp: 78.7, Rainfall: 4.1″

August: Temp: 77.5, Rainfall: 3.3″

Now, let’s examine some factors at play:

1. El Nino:  Although it’s impact on our summers is typically not as great as it is on our winters, El Nino will play a role in how this one pans out.  “El Nino” refers to warmer than normal sea surface temperatures over the Central Pacific Ocean waters close to the equator. 


When this pattern shows itself during the summer, more times than not we will see a large ridge of high pressure build over the Western/Central U.S. with a bit of a trough over the East.  Pictured below is the way I see the predominant jet stream pattern shaping up over the course of the summer.  Keep in mind there will be fluctuations in the pattern from time to time.



2. Southwest/Southern Plains Drought:  Perhaps you’ve heard about the recent California wildfires in the news.  Many parts of the SW United States and Southern Plains are bone dry…much drier than normal.  Drought begets drought, and as we saw here in South-Central KY two years ago, massive heat waves tend to build right over drought-stricken areas.  The lack of evaporation (a cooling process) from dry ground/vegetation often allows daytime readings to soar and become incredibly hot.  The Southwest U.S. is already getting a taste of that, and while I do NOT expect a repeat of 2012 here, we may feel that heat on occasion when the flow turns more southwesterly this season.


3. Great Lakes Chilled:  Let’s not forget, we just emerged from one of the coldest winters much of the country experienced in the past couple of decades!  A bi-product of that was the freezing of the Great Lakes, something that is NOT an ordinary occurrence. Lake Superior still more than half-blanketed in ice when this month began!  The slow melting of that ice cover will keep the Lakes cool well into at least the early part of Summer.  You may wonder, “what does that mean for us since we’re hundreds of miles south of the Lakes?”  Well, the wind blowing off those cooler Lakes will translate to cooler surrounding land, and at times, that air may be transported southward when troughs develop in the jet over the eastern U.S.  This may lessen our chances for seeing extended heat waves this season.


So, with those factors stated, here’s my outlook.  As always, this is just my own take on how I see Summer 2014 playing out and NOT an official First Alert Forecast.

Temperatures:   I do NOT look for a repeat of the kind of excessive heat we saw in 2012, when an all-time record high for June was established at sizzling 110 degrees!  I think with an upper wind flow often coming from the WNW, we’ll likely see temps wind up just a hair below average when it all shakes out.  That’s not to say we won’t experience a few very hot and humid days, and for us, that is NOTHING atypical.  Humidity may run high on occasion, since I think we could experience a bit more rain than usual.  Of course, the humidity combined with the heat makes readings “feel” hotter, but wetter soils tend to keep actual temperatures in check. But I think days that trip the National Weather Service’s “heat advisory” criteria (heat indices of at least 105) will be few and far between.

AVERAGE NUMBER OF 90 DEGREE DAYS FOR BOWLING GREEN IN A YEAR: 42* (*based on 1981-2010 average)

Number of 90 degree days last Summer: 22

*FORECAST NUMBER OF 90 DEGREE DAYS THIS SUMMER: Between 30-40 (below average)


*FORECAST NUMBER OF 100 DEGREE DAYS THIS SUMMER: I’m going to say none, although there may be a couple of close calls.  I believe several days could feature heat index values between 105-110.

Rainfall: A WNW flow aloft often keeps the pattern pretty active for Kentucky during the summer season.  It often results in disturbances that move along the flow, sometimes bringing us large storm clusters known as “MCS’S” (mesoscale convective systems).  These often dump a good amount of rain, although they can sometimes result in damaging winds, something that may keep us forecasters on our toes.  Things tend to become more dry as summer wears on, and I believe this one probably follows suit climatologically speaking.  I don’t think this season is as soggy as last Summer, one in which July 4th was washed out for many, but I don’t foresee our area returning to drought in the near future.


Total Rainfall from June 1-August 31, 2013: 18.17″

*FORECAST RAINFALL FOR THIS SUMMER: Between 11-13″ (Near to just above normal)

One more footnote to the precip amounts:  Remnants of a tropical system can skew the forecast totals quite a bit.  That possibility cannot be ruled out.

So there you have it.  I look for a fairly active pattern this summer, one that will be stormy at times though not as soggy as 2013.  And while there will be a few scorchers, this season will not rub shoulders with those from the Dust Bowl era of the 1930s or the record-shattering Summer of 2012.

Have a great Summer!


Remembering January/February 1994: Winter’s TKO

If you’ve watched our weathercasts over the past several days, you’ve probably heard 1994 mentioned a time or two.  Monday featured some of the coldest daytime readings South-Central KY has experienced since then.  It’s been frigid, no doubt, but readings from the past two days don’t even hold a candle to the kind of temperatures and wind chills this state dealt with 20 years ago!  Not to mention, the kind of snow and ice that preceded that cold.  And that event was followed by another crippling ice storm just a few weeks later in February.  Some of you may have better recollections of the second one, and for good reason.  Back to that in a moment.

The night of January 16, 1994 was one of those times when all the right ingredients for a major winter storm came together for the lower Ohio Valley.  Arctic cold was already in place.  Bowling Green woke up to a reading of -1, which is the last time we had subzero with no snow on the ground.  The temperature climbed into the upper 20s late that afternoon and evening as clouds rapidly increased.  Winter Storm Warnings had been hoisted for the entire region. By nightfall, a messy mix of freezing rain and sleet had developed across Western KY, spreading eastward as the evening wore on. With the ground already very cold, roads quickly became icy and treacherous.  To the north along the Ohio River, the mix changed to a very heavy snow in Paducah, Owensboro, and Louisville. “Thunder” snow was reported in some spots, with snowfall rates near 3″ per hour at the height of the event! 

The change from a mix to snow worked southeastward through the night, reaching Bowling Green before daybreak on January 17th.  While the city didn’t get in on the really huge snow totals seen over the northern half of the state, about a half a foot of snow fell on top of a 1/2-1″ of ice in the city before the snow moved out early that afternoon.  The heavy snow/ice accumulations weighed down trees and power lines, causing electricity to go out for thousands.  As temperatures tumbled from an early morning high in the lower 30s down into the teens by evening, all travel came to a halt!  In fact, then Governor Bererton Jones declared a State of Emergency for the entire Commonwealth.  All interstates and parkways were shut down so they could be cleared.  But clearing the ice and snow was easier said then done.


Things went from just plain cold on the 17th to INCREDIBLY cold on the 18th and 19th!  The core of a frigid arctic air mass settled into the region on the 18th.  Daytime temperatures hovered near 0 in Bowling Green, with wind chills near -20.  As skies cleared and winds relaxed on the morning of the 19th, record low after record low went by the wayside.  Most reporting stations across South-Central KY dropped into the teens below 0, some even into the -20s! 


With readings so cold, salt was rendered useless on Kentucky roads for several days after the early week winter storm.  This kept a lot of roads impassible, especially rural routes.  Some places were only reachable by helicopter.  And that wasn’t the only problem the cold caused.  Natural gas explosions took out several homes near downtown Bowling Green during the height of this arctic outbreak.  The extreme cold made putting out the large fires that ensued very difficult for firefighters.

By Thursday the 20th, a slow warmup and gradual improvements were underway.  At least one lane of I-65 and the Natcher Parkway were opened, with both thoroughfares reopen by Friday as the State of Emergency was finally lifted.

Old Man Winter’s one-two punch had come and gone. The next few weeks saw generally milder weather for Kentucky.  Then came the “TKO”: February 1994.

Few could have believed a paralyzing ice storm was just hours away from developing on Tuesday, Feb. 8th. The high that day reached a near record warm 72 degrees!  A sharp cold front came through that night, bringing thunderstorms along with falling temperatures.  By 6:00 the next morning, the mercury had fallen to 32, with rain changing to freezing rain then to snow as readings continued to fall into the 20s.  Travel became hazardous on the afternoon and evening of the 9th. 

Snow and ice stopped falling for awhile on the night of the 9th into the morning of the 10th…perhaps leading some to believe the worst was over.  That was far from the case.  A renewed round of moisture moved in from out of Arkansas and West Tennessee that afternoon.  The air aloft had warmed while surface temperatures were still in the mid 20s.  This was a recipe for trouble.  Rain began falling in Bowling Green around mid-afternoon, freezing on contact.  That rain continued all the way into the afternoon of the 11th before it finally tapered off to drizzle and ended that night.  But the damage had been done.

Bowling Green’s total for precipitation at the airport for the 10th & 11th: 1.61″, ALL of that coming as freezing rain!!  Up to 2″ of ice was reported in nearby Barren and Allen Cos, with up to 3″ of ice to the east in London.  Just as we’d seen a few weeks prior, most South-Central KY counties were back under States of Emergency.  Power substations froze, and at one point nearly 200,000 people in the state had lost electricity. Utility lines and trees were draped across roadways with travel virtually impossible during and immediately after the event.  For some homes and businesses, power was out as much as two weeks after the event.  Below is a shot from Cave City taken 2/11/94:




That, my friends, was the TKO. January and February 1994 truly were a couple of ROUGH months for winter weather in South-Central KY…the kind we have not seen the likes of since!

Update on Sunday Snow and Bitter Cold That Follows

First of all, for anyone hoping for a BIG snow in South-Central KY, it looks like any shot for that is out the window.  Morning computer model runs have been trending warmer tomorrow. This is due to a more northwesterly track depicted by the low pressure system responsible for the rain and snow chances.  If you’re a lover of snow, a track right over Bowling Green – much less one to the west – is not what you want to see.  To get a really good snow here, you would want to see a track to the south over the Tennessee Valley. Such a track does not appear likely now.


With most guidance trending this way, it now appears our precipitation will fall mainly as rain before a changeover to *some* snow late tomorrow afternoon.  With the snow’s duration looking shorter now, it’s looking like 1-2″ totals will be more common than the 2-4″ we were thinking yesterday, and 2″ may be a stretch. Models often fluctuate with the ultimate track of storm systems, and that’s a BIG reason why we always stress things can and often DO change with regard to projected snowfall amounts from winter storms.  

This is NOT to say we will not have any issues with hazardous travel tomorrow evening.  I fully expect we will.  Much of those issues could come from “flash freezing” of water/slush on the roadways as temperatures quickly dive into the 20s and teens tomorrow night. Gusty winds could blow around any snow that accumulates.  Icing in roads won’t go away easily since temperatures are forecast to dive into the single numbers late Sunday night.  When it gets that cold, salt is of little use.  Glazed roads are likely to persist through Monday, as well.  And speaking of the cold…

Sunday night and Monday continue to look AWFULLY frigid for us!  We’ll likely wake up to readings around 0 Monday morning with daytime readings only in the single digits.  Combine that with gusty NW winds 20-30 mph and you get wind chills that will bottom out in the -15 to -25 range!  We could see Wind Chill Advisories issued at some point late tomorrow into Monday. Be prepared!


That deep trough has BITTER cold written all over it!

The National Weather Service will hold a conference call soon.  We’ll keep you updated as to their thoughts, and Stephanie Midgett will have the very latest on snow amounts and how cold temps and wind chills will get tonight on WBKO @ 10!



Still Dreaming of a White Christmas??

Well, if you are…as they say in New York City:  “Fahgettaboudit”!  (translation: forget about it).  Allow me to explain why.

On my last post here, I mentioned that models were honing in on a major storm system affecting the Ohio Valley the weekend leading up to Christmas.  That much is still on the table, though it will be a rain and thunderstorm producer for us Friday through Sunday.  There’s even potential for minor flooding and strong storms to go with it.

Once that system sweeps out of here Sunday night, a cooler but quiet weather pattern takes shape through Christmas Day.  It’s worth noting the models have really backed off what once looked like brutally cold air plunging into Kentucky next week.  The newest runs keep the coldest of arctic air confined to Canada, the Northern Plains, and the Upper Midwest.  It still appears chilly, but it now appears likely our temperatures will moderate on Christmas after a quick cold shot Monday into Tuesday (Christmas Eve).


Even with colder air present Monday and Tuesday, it takes moisture to create snow, and that won’t be present in our area, either.  High pressure is expected to move over our region during that time.  Here’s one model’s take on forecast snow depth through Christmas Eve.  While this could change a bit, notice how far northwest of the Blue Grass state one has to travel before finding at least 1″ of snow on the ground.


So as far as our chances for seeing a White Christmas in South-Central KY, it’s 4th and long, and the punting unit is coming out on the field.  Maybe next year.


Is the “Dream” Alive?

“…where the treetops glisten, and children listen…to hear sleigh bells in the snow…”

So here we are, just two weeks away from Christmas Day.  It’s that time some of you may start wondering, “is there ANY shot for a White Christmas in South-Central KY this year?”  History tells us that chance is very small, but we can never say never!

In order for a Christmas to be “white”, a couple of pieces of criteria must be met:  1.) At least 1″ of snow observed on the ground on Christmas morning, or 2.)  At least 1″ of new snow falling on Christmas Day.  Sounds simple, but if you’ve lived here long enough, you know meeting that criteria is easier said than done.

Here’s a list of “official” White Christmases for Bowling Green dating back to the 1800s (data courtesy of Louisville’s National Weather Service):

1880:  4″*

1899: 1.2″

1909: 4″

1912: 2″*

1914: 3″*

1935: 4.5″

1962: 2″*

1963: 6″* (most snow observed in BG on Christmas)

1966: 3″*

1969: 3.4″

1989: 1″*

1992: 3.5″

1993: 1″

2010: 1.1″ (4″ on ground)

*observed snow depth

When you count them up, you find that an “official” White Christmas has only happened 14 times in the last 134 years for Bowling Green.  Not very good odds for “snow birds”, that’s for sure.  BUT…I think it’s worth noting that when we do see White Christmases here, they tend to come in “bunches”.  Note there were three between 1909-1914, four in the 1960s, and three between 1989-1993.  Our most recent, and it was a quite memorable, happened just three years ago.  That’s when nearly 4″ of the white stuff fell on Bowling Green on Christmas Eve with an additional inch falling from snow showers on Christmas Day.

Speaking of the odds, here they are for the nation as a whole based on climatology (courtesy of NOAA): 


 For a sure bet of seeing 1″ of snow on the ground on Christmas Day, one usually has to go north – sometimes WAY up north – to see a mantle of white covering the ground.  Every year is different, though. 

So what about this year?  Well, it’s still far too soon to say with great confidence whether or not Bowling Green will experience a White Christmas.  But the long range models do offer some clues as to what may transpire between now and the 25th. 

Of course, this is NOT a forecast and the details are fuzzy this far in advance, but a couple of models are converging on a strong storm system affecting the Ohio/Tennessee Valley region toward the end of the next week (around the 20th/21st). 


This could be a heavy rain or even thunderstorm producer for us before a blast of VERY cold air arrives in its wake late next weekend and early the following week (22nd and after).  Below is one model’s projection for temperatures relative to averages for Christmas week.


It looks mighty chilly for much of the country!

If that cold air verifies, the question turns to moisture and the availability of it.  Does the system potentially affecting us on the 20th-22nd deliver a shot of at least some snow as it departs?  Or will there be another weathermaker in its wake closer to Christmas itself?  It is simply too soon to answer those questions right now.  But the moral of the story…our chance for a White Christmas is NOT at zero yet!


Shane’s 2013-2014 Winter Weather Outlook for South-Central KY

             Leaves are falling, the days are getting shorter, and the nights are getting colder.  Yes indeed, winter is just around the corner.  With that in mind, it is time for me to make my annual stab at a forecast for the upcoming season.  I know winter has been on the minds of many even since late summer.  That’s understandable, especially since our summer was a wet and relatively cool one.  I’ve had MANY a person ask me, “Does this cool summer mean we’re going to have a harsh winter?”  My answer to that: “Not necessarily”.  While it’s true the winter that followed our last really cool summer (2009) was quite cold and snowy, the winter that followed 2004 (another cool summer) was quite mild, especially after Christmas.  I think mid-autumn patterns (October/early November) have more bearing on how the upcoming winter plays out.  That’s a big reason why I never bite on these forecasts until November.

              I should remind everyone there is SO MUCH to consider when comprising these forecasts.  Having them verify when all is said and done is even more difficult.  In fact, that part is out of my hands completely!  One thing that makes the challenge enormous is that no two winters in South-Central KY are exactly the same.  Remember, it was just a few years back when Bowling  Green experienced back-to-back double digit snowfall seasons (2009-’10: 15” and 2010-’11: 21”).  On the other hand, the last two seasons have been duds for “snow hounds”.  The average annual snowfall for BG is 9” (based on 1981-2010 data). 

              I think it’s also important to keep average monthly temperatures in perspective.  January is typically our coldest month, with an average temp of 35.7° (that’s all the highs/lows combined).  It’s closely followed by December (38.6°) and February (39.8°).  Although the onset of Spring falls in March, not to mention the month is excluded from what is known as “meteorological winter”, it can be chilly (March 2013 was!), with 48.4° being the month’s average reading.

              Now, let’s discuss the factors or atmospheric “players” that I took in consideration for this forecast.  The language gets a little “weatherese”, so bear with me.

1   *El Nino-Southern Oscillation (ENSO):  In a nutshell, this refers to the warming or cooling of the Pacific Ocean waters just north of the equator.  If abnormal cooling is taking place, then we have “La Nina”.  If warming is happening, it’s “El Nino”.  So what about this year?  Well, it appears neither condition is likely to be present since water temperatures in the Central Pacific are forecast to remain close to normal.  That’s what we call an “ENSO Neutral” condition.  There’s some suggestion we could see a weak El Nino try to develop late this winter.  That could throw a monkey wrench in my outlook down the road.  For now, though, I am of the belief that ENSO will NOT be a big player this season.                            

* NAO/AO (North Atlantic Oscillation/Arctic Oscillation):   These two are the wild cards, especially the NAO.  The North Atlantic Oscillation refers to a blocking pattern that exists in the North Atlantic Ocean.  A “positive” NAO happens when an upper low situates itself between Greenland and Iceland while a strong upper high is parked near the Azores off the coast of Spain and Portugal.  When that low in the North Atlantic breaks down and higher pressure builds there, blocking of the polar jet stream can occur (aka a “negative” NAO). This can send the jet plunging deep into the eastern United States, bringing colder air our way.  This is especially true if the AO works in tandem with it.  Basically, a “positive” AO means pressures over the Arctic Circle are low, which tends to cause cold air to sit and “well up” near the North Pole.  A “negative” AO, on the other hand, means pressures are rising in the arctic, often forcing cold air southward. 




         In the last several winters, these AO and NAO have arguably been the biggest players in terms of the overall pattern.  But trying to predict how these two will interact and behave over the course of a three month period is darn-near impossible!  That’s because there is very little skill when it comes to computer model projections with these indices beyond two weeks out.  These are highly variable pressure patterns, unlike El Nino or La Nina, which are driven by sea surface temperatures that change more slowly with time.  My gut feeling is that we probably won’t see a blocking pattern establish itself over the North Atlantic for too long a period this winter, which leads me to believe this could be a “see-saw season” for us.

3.  *Pacific-North American Pattern (PNA):  The PNA deals with the relationship between the circulation pattern over the northern Pacific Ocean and the existing pattern over North America. A “positive” phase of the PNA results when high pressure sits close to Hawaii and over the western part of the lower 48, while low pressure resides just south of Alaska and over the southeastern part of the lower 48.  When combined with a negative NAO/AO, it can make for very chilly temperatures in the Blue Grass state, sometimes setting us up for big snows IF an active subtropical jet is present.


4.  *Snow Cover/Arctic Sea Ice:  Not much has been said about it, but there’s actually been an uptick in the amount of real estate near the North Pole covered by sea ice vs. this time last year.  In theory, cold begets cold, and the more ice there is over the arctic, the more cold air can develop and sustain itself.  It remains to be seen whether or not this increase in sea ice can extend for another couple of years or if the overall decline in it over the long haul continues.  I do think it has some bearing on how cold our temperatures get when arctic outbreaks occur, though.  


 5.   *Other Factors (Sunspots, AMO):  It’s worth noting the increasing sunspot activity over the past three years.  Exactly what impacts these sunspots have on Earth’s overall global temperature is very much up for debate.  It is interesting, though, that some of our coldest, snowiest winters coincide with downticks in solar activity (i.e. 1917-1918 and the late 1970s). 


            On a different yet somewhat related subject, the AMO (Atlantic Multidecadal Oscillation), MAY be one reason – along with sunspot cycles – so many recent winters have been fairly mild.  The AMO deals with sea surface temperature trends over the North Atlantic Ocean.  The chart below shows how these temperatures have fluctuated over the past 150 years or so.  Note the areas in blue (1900-1920s with another in the late 1960s-early 1980s).  These coincide with some of the most brutal winters Kentucky has ever seen.  Right now, however, we are in a “warm” cycle of the AMO.  But the AMO has trended a bit cooler since the mid 2000s. 

Will this trend continue?  I don’t think anyone has a definitive answer to that question.  Some believe the AMO could go into a “cold” cycle within the next decade or so.  Should that happen, it may increase the chances for us to experience more of the kind of harsh winters we had back in the 1960s and ‘70s. 


ANALOG YEARS:  Listed below are winters that had atmospheric patterns and ENSO conditions closest to those expected for this season.  These are what we call “analog years”.  Total snowfall amounts for those seasons are listed in parentheses.

1980-’81 (9”)

1989-’90 (7”)

2001-’02 (3”)

2003-’04 (5”)

Month-to-Month Outlook

              If you’ve reached this far without your head spinning too much, kudos to you!  Now that I have discussed the “players” I took into account when making this forecast, let’s dive into the forecast itself.  I will focus on the three months that make up “meteorological winter” (December, January, and February), though I would not be surprised if measurable snow takes place in March once again, as it did this past season.

              First, allow me to get the obligatory annual disclaimer out of the way:  This is NOT an official First Alert Storm Team forecast!!  It is simply my take on how I think the season plays out.

DECEMBER:  This is a month that could prove to be a microcosm for how the rest of winter shakes out.  There’s a lot of indication in the long range models that November could end very cold with the chill lingering into the first week to ten days of December.  We’ve been spoiled with mild days on our first rounds of Christmas parades these past couple of years.  It could be a different story this time, though.  It does not appear as if the cold will persist through the entire month, though.  There are indications that a large ridge of high pressure may anchor itself over the Southeast during the month.  If so, a flip to a milder pattern will take place, one that could hold even through Christmas.  Our last White Christmas was in 2010.  Since history tells us White Christmases seem to come closely together for Bowling Green, the chance at seeing one can’t be ruled completely out.  But with the way I see the month unfolding, the late Bing Crosby would probably cry rather than croon.  Maybe more of a Jimmy Buffett “Christmas in the Carribean” (you may have known I would go there).

Forecast average temperature:  (39°-41°, one to three degrees above normal)

Forecast precip:  Slightly below normal

Forecast snowfall: Trace to ½” (Below normal)

JANUARY:  In most years, this month is the coldest of the bunch.  This one could start fairly mild, however, especially if the Southeast high pressure ridge holds its own.  There is some indication that much colder air could return by the second half of the month.  This could make for a volatile setup at some point.  Kentucky will often be right in the battle zone between frigid air just north and warm, moist air to the south.  We had to deal with severe weather during the early morning of January 30th last season, and it would not surprise me if a similar scenario unfolds again this January (always be prepared!).  If you’re a fan of the white stuff, some patience may be in order.  I don’t think we’ll be shut out completely in the snowfall department in January, but our best chances at a decent snowfall may wait until later in the season.

Forecast temperature: (35°-37°, near to slightly above normal)

Forecast precip: Near normal

Forecast snowfall: 1-2” (below normal)

FEBRUARY:  I believe it’s here where winter may finally show its hand.  If the Southeast ridge breaks down and more blocking develops over the North Atlantic, then there could be more opportunity for colder air to dive southward into Kentucky.  Also, IF a very weak El Nino tries to get going toward season’s end, it could result in a slightly more active subtropical jet.  This increases the chances for a wetter pattern, and if colder air is present, some snow.  One word of caution:  ENSO Neutral winters are infamous for ice storms in South-Central KY.  Remember the short-lived but nasty one we had in late January?  I think it’s highly likely we could see another significant icing episode this season.

Forecast temperature:  (36°-38°, one to three degrees below normal)

Forecast precip:  Slightly Above normal

Forecast snowfall:  5-7” (above normal)


Chances for seeing at least one or two significant severe weather outbreaks and/or flooding events:  60% with best chance coming during the first half of winter

Chances for seeing at least one icing event of a quarter inch or more:  40%

Chances for seeing a 4” snowfall from one system: 40%

Chances for seeing a 6” snowfall from one system: 10%

Total snowfall for the season: 7-10” (near to slightly below normal)

Chances for seeing a White Christmas: (historically 10%, this year, I give it 5%)

Coldest temperature:  Between 5° and 10°, most likely in February

So there you have it.  I think in the end, Winter 2013-2014 does not go down as ranking among our coldest or snowiest of all-time, but I do like our chances of seeing at least a little more snow than in the past two seasons.  I think most of the wintry weather comes from two or three systems, with many bringing just plain old rain or a mixed bag of precip quickly changing to rain.  There’s a CHANCE for one really decent snowfall (the kind that brings us at least 4”).  Otherwise, look for a “see-saw season” with no real dominant pattern.  It would not shock me if we hit 70° and 7° within the same week; that’s the kind of season I think it will be.  I hope you’ve had your flu shots and have cold medications stocked up and ready!

Remember, as with any forecast, there is ALWAYS bust potential!  For example, if the Southeast high pressure ridge builds more strongly than anticipated, then winter could wind up warmer with even less snow.  By the same token, if blocking patterns develop and the subtropical jet is active when/if they do, then we could wind up with a little more snow than I think.  I’m just calling it as I see it right now.

Thanks for reading! Let the games begin!