Friday Night Severe Weather

Good morning Arkansas! You've probably heard about or seen a few posts on social media regarding some stronger thunderstorms Friday evening. You may be asking, "why in the world are we dealing with severe weather in late November?". This is not all that uncommon, as much of the southern U.S. has a potent secondary severe season. A collision of two air masses, moderate instability, and some wind shear can spell trouble for Arkansas. 

The question is, do we have all of these ingredients for Friday? The short answer is sort of. We have wind shear, we have the collision of air masses, but we are lacking the instability. This sort of setup, (low CAPE, high shear) is also not uncommon for this time of year. Let's look at a few bullet points.

• It's going to warm up quite a bit on Friday, we wouldn't be surprised if some of southern Arkansas warms into the low 70's. 
• Some scattered rain is possible throughout the day. However, any organized thunderstorms shouldn't occur until after 4-5 PM.
• Several areas of thunderstorms could be on-going by 9-10 PM. The question is how many of these storms will be severe criteria storms. 
• By Saturday morning, most thunderstorm activity will be out of the state. 
• Our main risks for these storms are hail, damaging winds, and a moderate tornado threat.
• This is a concerning event, as we still have numerous high school football games to be played. Each school should have someone to pay close attention to the weather Friday evening.

The Storm Prediction Center has issued an enhanced risk area (orange shading) for a large portion of Arkansas. A lower tier slight risk (yellow shaded) has also been issued, with most of the state with the potential of seeing some stronger storms.

Friday Early Afternoon

By Friday afternoon, some of us will begin to experience some scattered showers and maybe a few rumbles of thunder. No severe weather is anticipated in the early afternoon.

Friday Evening

By Friday evening, we will begin to see an uptick in thunderstorm activity. There will be a severe risk with these storms, but we feel like the biggest threat is still to the west near Oklahoma. Notice how western Arkansas has been quiet for the most part, this could be a bad thing as instability is able to rise.

Late Friday/Early Saturday

By late Friday night/early Saturday morning, thunderstorms are still on-going. Some of the thunderstorms that do occur during this time frame could be the strongest, especially across western Arkansas. 

Saturday Morning

By Saturday morning, most thunderstorm activity is well to the east of Arkansas. Don't let the mild weather fool you, we will be back to freezing cold very soon. Also, some of us may see some more winter weather in the not too distant future! :)

-AW

Another Round of Snow!

Yes, you read this blog title correctly, more snow is possibly on the way! A trend over the last few years has kept warmer temperatures persistent through the months of October and November. This trend was ended this year, as we've experienced very cold temperatures thus far. A rather strong area of low pressure aloft will help aid in giving us snowfall chances Wednesday/Thursday. Instances involving a strong upper-level low can become somewhat difficult to forecast, as the track can completely alter a previously published forecast. However, confidence is high that areas across eastern and northeastern Arkansas could see an accumulating snowfall tomorrow evening.

Snow covered roads from 2012 in Sherwood (Pulaski County)

Some areas across central Arkansas and even portions of southern Arkansas may see a few flakes flying. In fact, moisture content could support snowflakes well across our state tomorrow, depending on temperatures. This being said, our focus is certainly across eastern and northeastern Arkansas where snow chances are MOST prevalent as of this time. We have several model images and further information below.

First and foremost, a winter weather advisory has been issued (11-13-18 8:25 PM) for numerous counties along our eastern border into northern and northeast Arkansas.

Due to our highest resolution model (HRRR) not being able to forecast behind tomorrow mid-day, we are using the simulated radar from the NAM (3KM) for this blog. There are several time-posted model images below.

Wednesday Morning

During the morning commute tomorrow, the NAM is suggesting some of us across southeastern Arkansas could see a few snow flakes already flying. Beware, this model could be overestimating this system. A safe bet would suggest this could be a very cold rain, or a winter mix. Nonetheless, don't be surprised if some of you see some snow early tomorrow morning. We believe this would be light and NOT cause any problems. However, we've been wrong before and some models do disagree (NAM) with this thinking.

Wednesday Evening

During the afternoon hours you can really see the low cranking forward in the simulated radar images. Data is suggesting the track will follow along our eastern border during it's track north/northeast.

Early Thursday Morning

Most model data is adamant that snow showers could linger into the early hours of Thursday morning, before finally exiting the state. Just how long the track of this low keeps this system stagnant in Arkansas is hard to forecast. This could also alter snow totals, as a slow moving track would support slightly higher totals!

Now for the favorite part, snow totals! Models are somewhat in agreement of where the most favorable areas for accumulation are. However, there is a few slight differences, see below.

EURO Snow Totals

The ECMWF (Euro model) is one of the more accurate models we use. It handled our recent event quite nicely, and we're confident in the data shown here. It does appear that 2-3 inches of snow could fall across portions of northeast Arkansas. With lower totals across eastern Arkansas (1 inch or less). Yes, it does appear possible that some snow could fall across central and maybe even NWA tomorrow. However, this snow fall SHOULD be light and not amount to much of anything.

GFS Snow Totals

The GFS model is also pretty similar, with most of the snow accumulation across northeast and eastern Arkansas. Notice this model is not as excited about snow chances over central and even NWA. This doesn't mean these areas cannot or will not see any snow.

NAM Snow Totals

Lastly, we're looking at the NAM model regarding snowfall amounts. Notice this model is not as similar to the other two. While snowfall is still expected across NE Arkansas (as seen in this model), more attention is shown across southeast Arkansas. We don't really agree with this models suggestion, but we still posted it regardless. We do believe portions of southeast Arkansas could see some light snowfall or a winter mix, but not 2-inches worth!

This could certainly cause issues on the roadways Wednesday evening and early Thursday morning. School closings are possible, we'll post those closing here on our blog page in our "school closing" section. Remember, we are dealing with a strong upper-level low. These sort of systems have been notorious for changing quickly and drastically altering the outcome of an event. If this were to occur, we'll have continuous updates on our Facebook/Twitter.

Thank you for reading!

-AW

November Snow - Who is in, who is out!

First and foremost, forecasting snow (or any winter weather) is one of the most challenging things in the field of meteorology. We may have an idea on how a scenario will play out, but winter weather has a vast mind of it's own, and will do as it pleases. With this being said, it is still a lot of fun to attempt a winter weather forecast. During this time of year models will gradually begin to bring snow/winter mix into the longer range solutions. These solutions usually get thrown around and then vanish.

Snowy weather back on January 20th, 2011 in NWA.

What we look for in models regarding winter weather is a trend and consistency. Over the last few days we've seen both of these things. There is some vary among the models, some sort of outlandish, but there is consistency. Let's take a look at a few bullet points before we look at some model output.

• The time period we're speaking of is on Monday evening (11-12-18). Prior to any winter weather, most of us will see some rainfall. It will be a cold rain as well, with temperatures ranging in the 30's and 40's. 
• The changeover for any sort of wintry precipitation would likely occur after 3-4 PM. This will mostly involve the northern half of our state. Don't lose hope yet though, we'll show you a few models below that say different.
• As of right now, this does not appear to be a "big" snow as one might call it. A dusting to maybe 1-2 inches in spots is possible, but we don't feel comfortable going beyond that. As we mentioned earlier, winter weather has a mind of it's own, so be prepared...
• By Tuesday afternoon we're completely dry, but very chilly with temperatures struggling to climb out of the 30's during the afternoon hours. 

Now for the favorite part of the blog, the model data: 

***DISCLAIMER***

This is just model output, each scenario could play out, these models are NOT our own forecast. We'll have our own forecast at the end of the blog.

GFS

First, we'll take a look at the GFS model. This model is notorious for being very aggressive with precipitation and temperatures. This can be a deadly combination for a forecast, as the models are really over-doing temperatures which lead to more snow/winter weather output. This model image looks really nice for snow lovers, which shows a nice swath of snow moving west to east. 

However, this is just one model and likely a bit much.

ECMWF

Next, we'll take a look at the ECMWF, or "Euro" for short. This model is by far the most conservative as far as wintry precipitation. Notice NWA in this model image is cold enough for anything frozen, while all else is just a cold rain. This model is by far the most boring output, but usually one of the more accurate. If you are a snow lover, this model is NOT your friend. However, if one was to bet on this system, this model would be a handy sidekick.

NAM

Lastly, let's take a look at the North American Model or "NAM" for short. This is the 18z run, let us tell you now, this model has gone absolutely bonkers. The amount outputs show values of right at 10 inches of snow Monday evening. Yes, you read that right, 10 inches of snow. Is this likely? No. 

The NAM is sort of like the GFS, as it has a problem with overexerting temperatures and wintry weather in it's outputs. If you are a snow lover, this model is your friend, above of all else. Notice the model image has the snow/wintry weather (shaded blue) moving west to east and covering a large area. This model keeps the snow well to the south into much of the state, as we stated earlier, fun to look at, but highly unlikely.

As for our forecast, as promised, we're taking the more conservative route. Any winter weather could certainly reach further south than the area we have highlighted. If models begin to suggest different, we'll update our forecast and post it on our Facebook/Twitter. Northern Arkansas is certainly favorable for any sort of winter weather. We did not highlight it on this graphic, but the higher elevations of the Ouachitas could see some of the action as well. 

Bottom line, this is NOT a huge blizzard/snow storm. Winter weather could develop on the backside of the expected rain as temperatures dip below freezing. This could result in a dusting, to maybe 1-2 inches of snow in isolated areas. We'll have updates soon, as we continue to monitor data! Thank you for reading.

-AW

Dangerous Thunderstorms on Monday

***This will be a longer blog than usual, we plead with you to take the time to read thoroughly. Dangerous storms are possible Monday***

Arkansas' secondary severe weather season is in full swing, we will get a taste of this on Monday evening. Unlike our last round of severe weather, this could be a little more potent. Luckily, most of the state may be able to avoid the bulk of the nasty stuff. With this being said, our page covers the entire state of Arkansas, we don't want anyone being left out. Regardless of specifics, the threat of severe weather is possible for a large chunk of the state, but as we mentioned earlier, some of the nastiest stuff MIGHT occur just to the east of Arkansas. As all of you are aware, weather can change quickly, so we must remain vigilant over the next 48 hours. Let's look at some bullet points and get into detail.

• Storm chances will begin to increase on Monday afternoon, mostly across central Arkansas. Most of western Arkansas looks to avoid any major storm chances, but we'll watch that closely. 
• As of this morning, we believe the best chances for any organized severe weather will occur after 3-4 PM and last until around 12-1 AM. For those of you wondering about areas involved, we believe areas from central Arkansas and east to the Mississippi border have the greatest chances. We will have graphics below to better explain this.
• All modes of severe weather will be possible with this round of storms. Damaging winds, hail, heavy rainfall, and tornadoes are possible. There is a threat for stronger, long lived tornadoes with this event as well. Don't panic over this, we will have full a explanation on this below.
• Severe weather looks very likely on Monday, but hopefully thunderstorms will struggle to develop here in Arkansas. This is a possible outcome as storms may not fully strengthen until they move east out of the state. This is our hope, so cross your fingers!
• Our neighbors to the east, especially in the Mississippi River Valley look to take the full brunt of this system. Eastern Arkansas has the highest chances regarding severe weather on Monday, this is fully explained below.

SPC issued risk areas for Monday

The Storm Prediction Center has issued their outlook this afternoon regarding Monday evening. Most of our eastern border has been encompassed in an "enhanced" risk area. A "slight" risk area has also been issued covering areas well into central Arkansas. Some of this area could be upgraded to a moderate risk area before Monday evening, if so we will update this on the Facebook page.

Monday afternoon thunderstorm activity

We've included several model images to help better portray the possible time frame of the thunderstorms. The above posted model is valid for Monday afternoon, notice thunderstorm activity begins to increase in coverage. While not all of these thunderstorms will be severe criteria, some certainly could be. 

Monday evening thunderstorm activity

By Monday evening, there isn't much change. Thunderstorm coverage is still well underway, we fully expect these storms to be rather strong during their track east. Notice the increase of organized thunderstorm structure across eastern Arkansas.

Late Monday thunderstorm activity

By late Monday, we STILL could be dealing with some stronger thunderstorms. However, if you'll notice the storms are well on their way east out of the state. We cannot say for sure, but hopefully the severe weather chances will begin to decrease as thunderstorms continue to train over the same areas. 

Tuesday morning 

By Tuesday morning, the state is cool and quiet. All thunderstorm activity will be well to the east of Arkansas leaving us with cooler weather to start our morning. Temperatures could dip into the high 30's across northwest Arkansas Tuesday morning behind this cold front.

So now we've covered areas involved and a possible time frame for these thunderstorms. Now what about the severity of these storms? We mentioned earlier that there is a slightly heightened chance for tornadoes on Monday. Like our last event, the CAPE (convective available potential energy) is not off the charts, which isn't unusual for November. However, the atmosphere is showing signs of potentially being highly sheared. This simply means that winds will be turning with height, which ultimately leads to conditions conducive for tornado development.

Highest tornado probabilities 

We don't usually do anything like this, but we felt it was needed to help better explain our statements. Above we've included a graphic with an area highlighted in red. This area, in our opinion, has the highest tornado probabilities in regards to Monday evening. This does NOT mean that a tornado will not occur outside of the area we've highlighted. Rather, this area appears to have the needed "ingredients" conducive for tornado development, as we mentioned earlier. 

To conclude this blog we've included a graphic from the National Weather Service explaining the different issued risk ares. As we mentioned earlier portions of Arkansas have been encompassed in an enhanced and slight risk area. Hopefully after reading this blog you have a better understanding of the upcoming weather Monday. If anyone has any questions, feel free to message us or comment on Facebook. 

Stay weather aware!

-AW