"Arctic Blast" - Video Forecast Discussion - December 20, 2022

As the coldest December air in 33 years prepares to infiltrate the Mid-South just ahead of the busy holiday weekend, we review the atmospheric setup, the timing, the impacts, how to best prepare, and how long this cold spell will last! Below are a couple of the graphics used in the video to help summarize the event. 

 

Erik Proseus

MWN Meteorologist

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Arctic airmass intrusions and snow chances

While the cool, damp conditions and overcast skies of late are fairly normal for winter in Memphis, it appears Mother Nature may be poised to send "real" winter our way starting this weekend. While that means the collective antennae of Mid-South meteorologists are "up" for winter precipitation chances, the most likely result of this pattern change will be shots of Arctic air that intrude well into the mid-latitudes, including the Mid-South. Let's dive in!

Today and Friday - mild and mainly dry

Preceding the Arctic air, we'll get a taste of well above normal temperatures the next 48 hours or so, just to re-acclimate you to something semi-pleasant before lowering the Arctic hammer. Today's rain has shifted east for the most part with a weak Pacific cold front moving through late this afternoon. While that will briefly shift our wind around to the north, it won't get too cold behind that front. Look for lows to remain in the 40s overnight - no ice scraping in the morning! Friday will see continued mostly cloudy conditions, but most of the daylight hours will be dry with highs well back into the 50s as wind turns back around towards the south ahead of the next major weather player.

The NWS forecast chart for Friday shows low pressure to our west poised to move east with Arctic air on it's north side. A series of fronts are across the Mid-South. Most of the day will be dry but rain arrives by evening. (NWS)

Friday night through Saturday mid-day - warm and wet

Rain moves in Friday night with wind becoming gusty out of the south, which should hold temperatures up in the 50s during the overnight hours. A rumble of thunder is possible late Friday night into Saturday due to the strength of the incoming low pressure system and accompanying front. Rain continues into Saturday as we see temperatures rise to about 60 Saturday morning.

The NWS/Weather Prediction Center precipitation forecast for Friday at 6pm through Saturday at 6pm calls for more than an inch of rain for Memphis. (NWS/WPC)

Saturday afternoon/evening - the Arctic hammer

By Saturday afternoon though, it'll be as if Memphis was picked up and dropped 1000 miles north in Minnesota! That rude front will bring a doozy of an Arctic blast with temperatures dropping some 25 degrees by evening - into the 30s - and a north wind blows at 30+ mph! That's when things could get interesting for a minute as the Arctic hammer gets dropped...

While some precipitation will linger into the evening, the cold airmass could advance quickly enough to change the lingering precip over to the white variety. As of now (Thursday afternoon), I think we've got better than a 50% chance of seeing snowflakes after dark Saturday evening. However, I don't think it will amount to much. The dry Arctic air will wring out the atmosphere pretty quickly, and precipitation will be quick to exit. Accumulation chances appear to range from none to an inch with most of the metro likely to see 1/2" or less.

The NWS/WPC forecast as of Thursday morning for the "most likely" snowfall expected Saturday morning through Sunday morning. Note the 1" area sits just northwest of Memphis. (NWS/WPC)

The NWS/WPC forecast for a "reasonable worst case" (or best case?) for snowfall totals Saturday morning through Sunday morning. These values have only a 10% chance of being exceeded. So 1-2" is likely the most we could expect to receive and even that is not considered likely. (NWS/WPC)

Nearly all models are on board with the "less-than-an-inch" solution at this point. The holdout of late, our typically-esteemed European colleague, has lowered the potential as of this morning. The situation can still change of course, but that move brings it more in line with the American-bred models, raising confidence in the solution. More impact-ful snow totals and some ice is expected north of the Memphis region.

Sunday chill

By Sunday morning, all precipitation will be gone and clouds will be departing as well, but not the cold air! A brisk north wind will keep temperatures from rising much above freezing despite sunshine. That means wind chills in the teens in the morning and 20s in the afternoon. Brrr! One thing to be on the lookout for. especially Sunday morning, will be patchy ice. Temperatures drop quickly, after dark, immediately behind departing rainfall. It's conceivable that a "flash freeze" could result in spotty black ice. With lows in the mid-upper 20s and a stiff breeze blowing, I think our chances of that occurring are fairly low, but it's worth keeping an eye on.

Sunday night will be the coldest night of the forecast period as high pressure quickly builds in and shuts off the wind machine, allowing the mercury to dive, possibly into the teens outside the city.

Longer term - more of the same?

As quick as it turned cold, the Arctic high shifts east, "return flow" (southerly wind) re-engages, and we warm back up on Tuesday in time for an aftershock - more rain, warmer temperatures, and another Arctic front Tuesday night that could have us watching precip types again Tuesday night!

The week 2 (Jan 25-31) temperature probability outlook for the U.S. indicates well below average temperatures are likely for the eastern half of the nation. For Memphis, the Climate Prediction Center puts those odds at 77% for Memphis specifically. (NWS/CPC via PivotalWx)

The European model seasonal forecast indicates enhanced odds of below normal temperatures for the eastern half of the country during February. (WeatherModels.com)

It appears that this pattern of rising and diving temperatures may continue a while, as we head into a period of generally (on average) below normal temperatures that continues well into February according to most semi-reliable data. Like I stated in a previous blog, the long-range trends continue to show below normal temperatures for the eastern half of the country from next week through the end of the winter season. We'll see what the groundhog has to say about that in a couple weeks!

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook and Twitter for routine updates and the latest info!
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Liberty Bowl forecast, NYE snow chances, and more Arctic cold

The cold is here, and it's not going anywhere anytime soon! Unfortunately the best we can expect is some fluctuations in the magnitude of the cold, but not necessarily a full reprieve for a while.

Let's start with the near-term. After a couple of bitterly cold days, the next reprieve arrives tomorrow and Saturday when high temperatures climb to 40° (slightly higher Friday) after cold early morning hours. Wind actually turns southerly for a brief period Friday afternoon through early Saturday  before the next Arctic front seeps through the Mid-South Saturday afternoon.

For those attending the AutoZone Liberty Bowl Saturday, it will definitely be chilly, but it could be worse! Wind will pick up a bit during the game to around 10 mph, which will keep wind chills near freezing, though highs will reach near 40° during the game.

Though it will be cold, it won't even be in the top 10 coldest Liberty Bowl games on record. Below are the coldest Liberty Bowl games, courtesy of Bryan Moss-Namowicz of TigerSportsReport.com. The most recent bitterly cold game was January 2, 2010 (shown as the 2009 game) when Arkansas beat East Carolina, 20-17 in overtime, with a game-time temperature of 29°.

After Saturday, all eyes turn to New Year's Eve on Sunday, which is the day local meteorologists have been hemming-and-hawing over snow chances since the beginning of the week. At this time, confidence is increasing that we will see no more than flurries on Sunday with temperatures in the 20s all day.

The model history on this event is that the American GFS model was forecasting light accumulation of snow on New Year's Eve for about the last week, until Thursday night. The European model had insisted on dry weather for the same period of time. On Thursday, roles reversed. The morning European model decided light snow was likely Sunday. Meantime, the American model was backing off. The European snow lasted for two model runs (Thursday morning and evening) before it too returned to form. As of today, with the shorter-range NAM model joining the fray and the Canadian model kicked in for good measure, models are now unanimous that no accumulating snow is expected. Flurries can't be ruled out. And it will be bitterly cold.

The Thursday morning European model valid on Sunday shows precipitation to our west and south, moving to the southeast, missing the Mid-South. (WxBell)

The Thursday afternoon GFS model valid on Sunday also shows precipitation to our south, moving away and missing the Mid-South. (WxBell)

The Thursday afternoon NAM model valid on Sunday also shows precipitation to our south, moving away and missing the Mid-South. Overall, we currently predict only flurries for the metro. (WxBell)

2017 will end, and 2018 will begin, on a stupid cold note with highs in the 20s Sunday, Monday, and possibly Tuesday. Lows will be well down into the teens both Monday and Tuesday. It'll be a time to remember the pets, plants, and pipes! It looks like we may get back above freezing (briefly) on Wednesday before another round of cold air arrives to end the week. Looking long-term, a more significant warm-up looks to be on the horizon heading into the first weekend of January. Let's all hope! Check the latest MWN Forecast anytime via the web or our mobile app. Links are below.

Erik Proseus
MWN Meteorologist

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"10 Things You Should Know" with snow in the forecast

Several thoughts as another "2016-'17 Winter Season" #ArcticFront comes barreling our way.

1. Fortunately, severe weather didn't materialize in our area on Monday. Plenty of thunder (even thunderfog, which is almost as cool as thundersnow), but no high wind or hail. I'm good with that. I root for people, not storms, despite trying to produce a good forecast that sometimes includes them. Folks near the Gulf Coast weren't so lucky, including Gulf Shores.

2. At the end of the day, as the back edge of the afternoon rain shield moved across the metro, the setting sun produced some spectacular skyscapes. Some folks were treated to brilliant double rainbows, others to an awe-inspiring orange sky. Scroll through our Twitter feed for a bunch of cool photos you nice folks sent, like the one below!

The clearest double rainbow I've ever seen. Horn Lake MS 1/2/17 @memphisweather1 @NWSMemphis @joeysulipeck @WeatherNation #mswx pic.twitter.com/OsdaqByHE7

— KScho (@kschones84) January 2, 2017

3. Looking ahead, the Arctic front arrives early this evening. You'll notice the wind shift to the north and pick up pretty good if you're out. If you're out later, you'll notice it'll be a lot cooler than it's been in a few days. By morning, we'll be in the mid 30s with wind chills in the 20s. Bundle the kids up as they head to school! We could see a few stray showers with the frontal passage late this afternoon into early evening. They'll be relatively minor compared to rains of the recent past!

4. Very cold air hangs around for several days as the high pressure of Arctic origin makes its way across the northern U.S. We'll be on the south side of it, but it'll still be plenty cold. Expect lows in the 20s and highs in the 30s starting Thursday morning and continuing into early next week!

Low temperatures Sunday morning according to this morning's GFS computer model. Yes, the freezing line is as far south as central Florida with below freezing temperatures across the vast majority of the CONUS. (WxBell)

5. The million dollar question, and one that everyone wants to know the answer to, is will it snow and if so when and how much?? The latter part of that question seems to have taken on a life of its own given recent rumblings of "snowmaggedon-like" snow totals in the south from some folks who would rather share model hype rather than be responsible.

5a. BTW - we don't recommend getting your weather information from sports talk figures (I'm looking at you Clay Travis), just like you don't want my analysis of Grizzlies trade rumors. Neither of us knows what we're talking about. Stick to the experts who have skin in the game and have proven responsible in the past, and aren't out just for ratings or social media numbers!

6. The REAL answer is: I'm not exactly sure yet.  "But Erik, that's not the answer I wanted to hear!" I know, but it's the responsible answer at this point in time. I DO think there's a decent chance most of us could see some snowflakes. But I don't know exactly when and I don't know how much. YET. Maybe you've heard about how hard it is to forecast winter weather in the south (in particular)? Below are a couple of visuals to help you understand. Then I'll give you my first educated guess, since you asked...

7. First are the snowfall maps (all valid through 6pm Saturday) from the last 12 runs (4 per day) of the American-made Global Forecast System (GFS) model. Greys are light snow, blues are snowman builders, pinks are snowmaggedon. Notice how the snow starts to our north, drops the hammer right over us, then backs off again and sinks south.The last frame is from this morning's model run.

We also have this graphic which shows run-to-run consistency (or not) for the GFS model. Each row represents a run of the model. Exactly three of the last 15 models runs (or roughly four days worth) has produced more than 2" of snow.

8. But that's the American model... the Europeans are far superior, right??  I give you the European model (credit Weather Bell Analytics), same parameter, run twice a day. This is from model runs of the past 6 days:

Oh yeah...FAR superior! Haha! I will give it this though - the past couple of days it has been somewhat consistent. But it still varies from a dusting to about 2" here in the metro over that time as you can tell from the graphic below. Again, multiple (the last 11 to be exact) runs of the European model. Only one has forecast more than 2".

9. All that said, here's my best guess at the possibilities, with all the caveats applied and with medium-low confidence. Thursday night has a chance for some flurries or maybe a dusting (meaning less than 1/4"). I don't think it's the time period of greatest concern, as far as traffic problems, etc. During the day Friday, there's a better chance we could see some minor accumulation - I'm talking about maybe an inch on average. It'll be very cold and cloudy so it wouldn't go anywhere right away. An inch could be enough to possibly cause some slippery roads, especially those elevated ones we keep building, but it's not enough to even cover the grass. If I end up conservative, we could get 2 inches - but that's my upper bound right now. Flurries could linger Friday night into early Saturday, but that's also a low probability.

10. Should you get all worked up or start changing plans? No. Will schools be closed?? I have no idea. Just stay tuned. Listen to trusted sources who have proven their mettle in the past. We'll keep you sane and provide the "real deal," not the wish-cast. As the event gets closer, especially tomorrow into Thursday, we'll get more model data that is higher resolution within the forecast window of concern and things will hopefully start to become a little clearer. But remember, it's the south. It's snow. Those things don't mix, and that applies as much to forecasting it as it does to driving in it! Keep an eye on our social media feeds listed below for the latest. And if all else fails, "if it looks too good to be true, it probably is!" Don't share it.

Erik Proseus
MWN Meteorologist

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Strong storms precede Arctic cold & a commentary on storm warnings

As we predicted in our Friday evening blog, this was indeed a wild and wacky weekend in Mid-South weather. An Arctic cold front, bringing a surge of the coldest air felt yet this winter, sparked widespread thunderstorms along and just behind the front. Wind, both ahead of and behind the front, was a significant issue and the thunderstorms caused scattered wind damage of their own as well.

As the storms entered the metro from the north, cold air from the Arctic front started to out-run the storms and "cut off" their supply of warm air from the bottom, resulting in a lot of lightning and thunder (even as precipitation changed to sleet about 3 hours after temperatures started plummeting from the mid 70s) but little damage. However, in north MS, storms re-developed on the front and tapped into the warm air, as well as a little extra vorticity, or spin, provided by the front itself, and funnel clouds and possibly brief tornadoes resulted. (Tornadoes are unconfirmed at this time, as the National Weather Service has not completed storm surveys.)

Following the storms, temperatures were quick to fall. At MWN on the north side of Bartlett, the mercury fell from 75° at 7:20pm to 53° in twenty minutes, 44° in less than an hour, and into the 30s in less than two hours. The graphs below show the precipitous drop in temperature and subsequent rise in pressure behind the front.


Fortunately, precipitation tapered fairly quickly once the frozen stuff began to mix into the rain and only light amounts of sleet occurred. By Sunday morning, roads were mainly dry, or at least just a bit damp, with temperatures in the mid 20s and a biting north wind.

Moving on to the aftermath, the greatest damage I have seen via social media and news reports is a series of power poles snapped and an apparent fire at the Gateway Tire store on McIngvale Road in Hernando, across the street from Hernando High School on the east side of I-55, and some minor roof damage in an adjoining neighborhood.

Storm clean up underway in Hernando https://t.co/3DJaWJXTht pic.twitter.com/NCfMoYIPk3

— FOX13 Memphis (@FOX13Memphis) December 19, 2016

Re-creating the timeline of events, the first report of something suspicious in the area was actually an aircraft on final approach to Memphis International about 10 miles south of the airport at 8:45pm. The flight crew reported seeing a "possible tornado." There are some discrepancies with the report in that the pilot report (PIREP) location was provided as 10 miles south of MEM, but the actual text of the report stated "2 mile short final [approach to MEM]." Either way, something fishy was occurring in storms south of the airport. Within a couple of minutes of the report reaching the National Weather Service, a Severe Thunderstorm Warning was issued for the storm, at 8:54pm. Then a couple minutes later, public reports of power lines down (as described above) were received. Subsequent storms, beginning about a quarter past 9:00, prompted Tornado Warnings for eastern DeSoto County and points south and east (Marshall and Tate Counties in particular). However, a Tornado Warning was never issued for the storm that produced damage in Hernando.

Commentary

I have received several reports of "sirens not sounding" and an eyewitness in the news report above seemed to indicate that the storm hit without warning. I have a handful of comments. I'll try not to lose followers with these comments, but be forewarned, this part is commentary.

1. "Sirens didn't sound for this storm" is true. I have not (yet) talked to DeSoto County EMA, which is the agency responsible for the sirens, but there was no Tornado Warning, therefore they (properly) didn't sound. (A Tornado Warning WAS issued for eastern DeSoto County about 9:15pm for a different storm. I'm not sure if sirens sounded for that storm, or if not, why not. I'll try to find out.)
2. I'll be blunt. If sirens are your primary means of taking action in the face of a possible tornado, and you're inside, you're doing it wrong. Sirens are for outdoor use. With pounding rain, thunder, and strong wind, their range is limited and sound muffled. DO NOT RELY SOLELY ON SIRENS FOR YOUR WARNING SYSTEM. They serve a purpose. It isn't for indoor warning, even if one is not far from where you are. They are to let those outside know that they are in a dangerous situation and to go take shelter or, at the least, gather more information on the threat.
3. I had stated yesterday in social media posts that the tornado threat would be primarily limited to brief tornadoes that would likely occur in the line of storms. These types of non-supercell tornadoes are quick to touch down and lift and exceptionally hard to warn for given current technology. The NWS does a fantastic job, but if they were to warn for every thunderstorm that rotates, the false alarm rate would be close to 100% (because the vast majority of rotating storms don't produce tornadoes with damage) and more people (than already do) would not pay any attention to them. 
4. I'm assuming there was no Tornado Warning for the storm in question because the tornado (assuming one occurred, which isn't confirmed at this point) was brief and had lifted before the warning forecaster had even seen it on radar. Again, I haven't spoken to the NWS, but I have good friends who work there and I've observed warning operations in person before. The storm was at the least producing strong wind and a Severe Thunderstorm Warning was issued for those in the path of the storm moments later.
5. Blunt, again... I'm getting tired of hearing people say that the storm "hit without warning," or in this case, "I don't think anybody expected it at all." Now, MAYBE the person who said this in the article above meant that she (and "anybody" else, whoever that is) didn't expect it could actually happen to her. But all of the local (and even national) weather folks had been talking about the real potential for severe weather in our area at least since Friday (and it was mentioned by us a couple days before that). There was a Tornado Watch issued mid-afternoon, many hours before the storms arrived. For gosh sakes, it's December and the temperature is 75° with very humid air and a strong wind! If you somehow didn't know you were in a watch box, the conditions should've been enough to tell you that maybe you should be paying closer attention to a weather source! That particular storm doing damage in that section of Hernando might've not been predicted, but the fact that it COULD happen means it was not completely unexpected. 
6. It's 2016. You all have multiple options for staying abreast of rapidly changing weather conditions. I can tweet until my fingers fall off and the TV weatherman can talk until he runs out of breath, but if the public doesn't take some amount of personal responsibility for becoming a knowledgeable consumer, then our efforts are for naught. 
7. There's a massive push underway to put more "social science" in meteorology. Not only producing accurate forecasts and warnings, but creating and disseminating the products in a way that will result in the most eyes and ears taking notice, comprehending, and taking action against. I'm all for this. But I also know that there are some folks out there that you can tell a tornado is going to hit their house in 5 minutes with 100% certainty and they still won't respond. Lack of personal responsibility will always result in some people saying they "didn't know" that xyz was going to happen. It hit without warning! If you're reading this blog, I assume you're not one of those people. 
8. I'm all for better products and services that can reach the most folks and end in response and preparation, but I also believe that we (the scientists) can't sacrifice improving the science and accuracy of our products in the name of trying to figure out a way to personally hit some people over the head to try and get them to respond. The response is up to the individual, based on their individual risk and tolerance level, assuming they get the information. Personal responsibility says don't rely solely on sirens (or any single source, they'll all fail you at some point). Personal responsibility says you must take action if the information you have gathered results in a threat that exceeds your risk/tolerance level.

Be safe, be prepared, and be responsible.

Erik Proseus
MWN Meteorologist

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Weekend Update - Memphis weather style

Lots of activities going on this weekend in the Memphis area, involving tens of thousands locally and, literally, from across the United States.  It's St. Jude Marathon weekend and Christmas parade season!

Unfortunately, Mother Nature is not going to be too cooperative as we see a round of precipitation move up from the southwest and envelope the area during the day Saturday, lasting into the first half of Sunday. This rain will be caused by moist air rising up into the area ahead of a low pressure system that moves along the Gulf coast.

Here's what the North American Model (NAM) thinks radar will look like beginning at midnight tonight and ending Sunday morning at 6am:

NAM model forecast radar from midnight tonight through Sunday morning at 6am

Note that the greens are very light rain with the yellows being steadier, but not particularly heavy, rain. We're not talking about a deluge and no thunder will occur either. However it does look like we could start to see sprinkles early Saturday morning with basically increasing rain chances as we go through the day Saturday. With any luck, most of the marathoners will be done before rain gets very steady and it will be just a nuisance.

Here are a few key times pulled from the loop above. Note that these are not exactly what will be happening, but give us an idea of what to expect.

6am

Noon

6pm

And here's our #StJudeRun Memphis Marathon forecast:

As you can see, it's also going to be a chilly day with most of it spent in the 40s. Once rain gets going a little more steadily in the afternoon, it'll drop back down into the 40s after peaking near 50. Fortunately, wind is not much of an issue, though there could be a bit more (maybe 10 mph) in the evening. For late afternoon/early evening parades, the news is not good unfortunately. Steady light rain could possibly be moderate at times. Rain chances by late afternoon are above 50%. By Sunday when the rain moves out, rainfall totals will likely be in the 1/2"-1" range.

Next week

The pattern remains active the first half of next week. Another stronger, wetter system moves across the Mid-South Monday. Low pressure will move very close to Memphis Monday evening and a few thunderstorms are possible. Currently severe weather is not expected.

Finally, after dry hours Tuesday and the first half of Wednesday, another front moves through Wednesday night. This is the "Big Kahuna" Arctic front you've probably been hearing about. More showers and a few thunderstorms will be possible with this front before temperatures nose dive heading into the end of next week. We'll have more details on both of these systems in the coming days, but be prepared for the likelihood of temperatures remaining in the THIRTIES (really!) most of the day Thursday and maybe Friday too! We'll all see a hard freeze Thursday and Friday nights.

Finally a note of caution

Crap apps and nationwide weather outlets that use computer model forecasts may (already be) showing you snowflakes next Thursday. YES, it could be cold enough. However, we have no good indications that precipitation will be lingering by the time it gets cold enough to snow. We'll of course let you know if that changes. In the meantime...

Erik Proseus
MWN Meteorologist

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On Arctic cold and multiple winter weather chances

Cold weather has come to stay for a while and while it's not as cold as places to our north...

Sunday noon wind chill values. Graphic courtesy WeatherBell.

...it's still cold by southern standards! The cold air in place will mean there will be a few time periods I'll be watching for the potential for wintry weather. In addition, the coldest of the Arctic air will drop into the metro tomorrow.

A reinforcing cold front arrives tonight, which drops our mid 40s of today below the freezing mark for tomorrow. The front will mainly bring clouds and an increase in the north wind, but it will also try and "wring out" what little moisture is in the air. With temps falling below freezing, snow flurries will be possible this evening, mainly to our west. However, I'm not optimistic.  Here's what the mid-day high-res model thinks might be happening at midnight:

Very light snow/flurries is depicted over the metro by the HRRR model at midnight tonight. Graphic courtesy WeatherBell.

Most likely a non-event as far as precip is concerned. HOWEVER, it's a good thing the baby chicks aren't out at the bus stops in the morning! Here's what the high-resolution NAM model predicts for 8am Monday wind chills:

8am wind chills will be in the lower teens Monday morning if you have to go to work. Graphic courtesy WeatherBell.

Yep, lower teens! Actual air temperatures will drop to near 20° to start the MLK holiday with afternoon highs struggling to reach freezing. If you will be out tomorrow for work, or maybe to catch the Grizzlies annual MLK Day basketball game at the Forum, layer up! It'll be teeth-chattering weather!

Another cold morning is expected Tuesday as the kiddos head back to school with lows again near 20° but afternoon highs rebound a bit back into the lower 40s as clouds increase ahead of the next weather-maker. (It's also worth mentioning to make sure your pets are taken care of as far as a warm place to stay and water that won't freeze, especially from tonight through Tuesday morning.)

Speaking of the next system, the round of precipitation I'm most keeping my eye on arrives early Wednesday morning. It's won't be nearly as cold as previous mornings as wind shifts to the south, but we might still see temperatures bottom out in the mid 30s overnight Tuesday into early Wednesday morning. Depending on when exactly the precipitation arrives, a light wintry mix is possible during that time frame. I feel the best chances for anything freezing or frozen will be north of the metro as it will take a little longer for the cold to retreat north of that area. However, as Jim Carrey would say:

Well, I suppose! The NWS has highlighted the area they think will have the "best" chance (below), but you'll notice the confidence factor is still pretty low on that event. We'll keep our eyes on it!

Rain is expected through at least mid-day Wednesday as low pressure and a front moves through the region. A lull in the precip occurs Wednesday PM before another low pressure system tracks through the region Thursday bringing more rain chances. Both medium range models I look at routinely (the American GFS and European ECMWF) keep lingering very light precipitation in the area Thursday night and early Friday as more Arctic cold air spills south. This would be time period #3 to monitor for the potential for winter weather.

In sum, winter cold has invaded the U.S. with periods of sub-freezing air dropping into the Mid-South. With a storm track that also favors a weather system moving through every few days, we'll need to keep a close eye on the timing of these to gauge the respective winter weather chances with each. We'll keep you updated via this blog, our social media feeds (links below), and the MWN Forecast, which you can find on the web, mobile web, and our app (links also below).

And for those who wondered whether winter would ever arrive during our balmy December... it's here! :-)

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook, Twitter, and Google+
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