Active weather pattern ahead. Shower & t’storm chances next several days. Severe storm risk increasing for Sunday.

It’s a downright balmy morning across the Tennessee Valley early on this Wednesday. As of the 4:00am hour, temperatures across the region were still into the low to mid 70s (ignore Scottsboro’s reading over there; it’s been acting up the past few weeks!). This is thanks to mostly cloudy skies across the area and a more sustained southerly wind overnight beginning to increase low-level moisture across the area. Thunderstorms off to the west of the Mississippi River have died out upon their approach to the area, as expected, but we can’t rule out a stray sprinkle or shower during the morning hours.

There is a LOT we need to talk about concerning the next several days; so, we will start with a basic overview with the temperature trend and rain chances for the next 7 days. Temperatures look to stay warm for the rest of the week and the weekend, with daytime highs well up into the 80s and overnight lows between the mid 60s to near 70 degrees. We do spy some slightly cooler weather toward next week, however. Rain chances are on the way up as we head through the rest of the week and the weekend. Unfortunately, this will likely play havoc on outdoor plans you may have for the upcoming Memorial Day weekend. You will also notice that we’re highlighting some threats here of strong to possibly severe thunderstorms across the area over the next several days. From today through Saturday, the overall severe storm risk in our area is low (and a few of those days it’s very low at best), but we can’t rule out a few storms during that stretch with gusty winds or hail. However, we are already focusing our attention on the potential for a more organized and elevated risk of severe storms in the area on Sunday. We’ll talk more about all that as we go along!

Starting with today, the NWS Storm Prediction Center has a Level 2 of 5 risk of severe storms in place across western Tennessee and north Mississippi, and this comes as far east in our viewing area as Hohenwald TN to Waynesboro TN to near Burnsville MS. For a few 10s of miles east of there, they also have a Level 1 of 5 risk of severe storms that comes as far east as Lewisburg TN, Pulaski TN, the Shoals metro, down to almost Russellville AL. This is part of a larger severe weather threat that stretches from upstate New York and Pennsylvania all the way down deep into central Texas. Part of that risk also involves an elevated Level 3 of 5 risk of severe storms from central Arkansas back into central Texas. For our local area here, we will go ahead and say now that this is very much a “just in case” type situation for us. As we will show you in a moment, the threat for later today (it’s actually for this evening/overnight tonight) is more likely to play out with storms dying out before they arrive in our local area. However, models don’t always 100% correctly handle how quickly or how slowly severe storms fade out like that; so, the *safe* thing to do is stretch low-end severe chances into our area. We get it! We just think this initial wave of storms may evolve so that there might end up being very little impact to our local area. Here below is the “Futurecast” breakdown with the HRRR model, as it seems to be the only high-resolution model that’s had a good handle on the storm evolution off to the west so far early this morning… (You can click on each image to see it in a much larger size and resolution)

The HRRR model here may actually be overdoing the coverage of these morning showers it shows across the area based on how radar looks off to our west right now, but we can’t completely rule out a couple of showers or an isolated rumble of thunder this morning into the afternoon. It’s just a low chance of that though. Otherwise, expect partly sunny skies today with highs once again into the mid to upper 80s. We’ve brought daytime highs down a degree or two based on the added cloud cover today compared to yesterday. As we head into the evening and overnight, this is the reason why the SPC has the low-end severe risks for the area. Scattered strong to severe storms will attempt to move toward the area from our west as we head into tonight. However, they will be moving away from their better dynamic support and the higher instability as they move toward us, and it’s very likely they will weaken or possibly die out all together before reaching us. However, as mentioned earlier, sometimes models don’t 100% correctly handle exactly when this dying out process happens; so, we’ll be on the watch for one or two storms with gusty winds or hail tonight… especially in our western counties. The overall risk is low, however.

Thursday is another day that features a low-end threat of strong to severe storms across the viewing area, but it may actually have a better chance of “performing” in our specific local area compared to the situation today/tonight. The NWS SPC has a Level 1 of 5 risk of severe storms across just about the entire area, with areas south of Moulton AL and Decatur AL being the portions of our viewing area currently left out of the risk. This may be expanded a bit more to include those areas on the early afternoon update, and regardless, you’re close enough to it to pay attention anyway! Here is the general timing/evolution breakdown for Thursday once again using the HRRR model for a “Futurecast”:

A few showers or maybe even an isolated thunderstorm or two will be possible as early as the morning or midday hours. Otherwise, partly sunny to mostly cloudy skies can be expected with temperatures starting in the upper 60s and lower 70s once again Thursday morning before climbing into the low to mid 80s by the afternoon. As we get into the early to mid afternoon and the atmosphere destabilizes, a disturbance riding the stalled frontal boundary to our northwest may trigger a few scattered strong to severe storms across the area. Don’t pay attention to the exact specific placement that the model has for them, but rather the overall idea that they will be there. These are cellular looking storms, and there’s enough mid/deep-layer wind shear for them to possibly have supercell characteristics. That means they may have rotating updrafts. HOWEVER, the *low-level* wind shear that is needed for tornado development will be VERY WEAK. This means that, while we can’t 100% rule out a tornado, the threat will be VERY MINIMAL and the main concern with these storms would be gusty winds of 40-65 mph and hail that may get up to quarter or half dollar size. Lightning and heavy rain will also be a concern. Having said that, the overall severe threat itself is low, and it’s very possible that it may remain low/isolated enough that a severe thunderstorm watch wouldn’t be necessary. There just may be a couple/few warnings to deal with. These storms will move west to east across the area, and the HRRR has them continuing through about 6pm or so before shifting out; however, they may last a little deeper into the evening. This means there MIGHT be some potential impact on some of the graduation ceremonies that are scheduled for Thursday early evening. It’s not a big severe weather threat, and the tornado threat is VERY VERY LOW, but have someone monitoring the weather just in case! Additional storms will be possible later into the overnight Thursday night into the predawn hours of Friday (maybe a bit more widespread than what this model shows after 3-4am Friday early morning), but they would have a lower chance of being severe because of the loss of daytime heating and a lack of stronger wind shear to compensate for that.

The unsettled weather pattern continues through Friday and Saturday, but they severe storm threat looks like it may actually back off for a couple of days during this time period. The NWS SPC shifts their outlook areas off to the west of us for both Friday and Saturday. Still, off and on periods of showers and thunderstorms will be likely both days (during the day and night, although not non-stop all day either day), and a couple of storms could be strong with gusty winds or small hail either day.

The system that’s getting our attention more approaches the area Sunday and Sunday night, however. A strong upper-level system will eject out of the Southern Plains toward the Mississippi Valley, and this will send an intensifying surface low pressure across Missouri and Illinois with a cold front approaching the Southeast. All the necessary ingredients seem to be coming together Sunday into Sunday night for a more organized severe storm threat across a large part of the Lower/Mid Mississippi Valley, the MidSouth area, and the Ohio and Tennessee Valleys. The Storm Prediction Center maintains the equivalent of a Level 2 of 5 risk of severe storms across our entire area, but they have flagged areas JUST to our northwest already in an elevated risk that is the equivalent of a Level 3 of 5 risk. Based on consistent model data, it is very possible that the more elevated threat level could expand into some part, if not a large part, of our local area in future outlooks as we get closer.

With this still being several days away, there’s still a lot we don’t know because it will be the smaller scale details we can’t see a couple of days out that will determine the ultimate outcome of this threat. However, the larger scale setup is one that has produced substantial type severe weather threats in the past, even this late into the spring severe weather season. Keep in mind that our tornado “season” here in the Tennessee Valley actually runs through the end of May, and we have had significant tornadoes in our area not associated with tropical systems as late as the latter part of June on occasion! While it’s too far out to determine the magnitude (how serious) of a threat this will be… especially for our north Alabama/northeast Mississippi counties, this does look like a situation where all threat “types” will be possible. That means that, in addition to damaging straight-line winds and large hail, there will probably be some degree of a tornado threat. We just don’t have the smaller scale details necessary yet to determine the magnitude of that possible tornado risk. Remember back on May 8th, we didn’t have a consistent enough signal for the supercell tornado potential for that evening until we got to the late morning and midday hours the day of the event! When you get late into the season like this, the wind shear necessary for tornadoes can still be adequate, but it’s often not as clear cut and obvious in advance as it is from the fall through the earlier spring months. Sometimes the tornado threat is tied more closely to leftover boundaries from storms the night before or morning of the event, and that’s something we can’t get a handle on until we get much closer.

With there being several rounds of showers and thunderstorms over the next few days, we may have to watch our for flooding and flash flooding eventually at some point. Right now, there isn’t enough consistency in the data to highlight in particular a specific period of time when that may be more likely, but I would imagine we may get into a situation where at least some localized flash flooding potential is possible by late in the weekend, if not earlier. We’ll be working to fine tune that potential over the next few days too!

With all of that said, what’s important is that you plan ahead and stay in touch with us for forecast updates. We will be working to sort out all those details over the next few days as we get closer. We know with this being a holiday weekend ahead, many of you may be urged to “unplug” for the weekend as you carry out your plans. We URGE you to still check forecast updates and don’t disconnect from weather information over the weekend, especially on Sunday! It may be critical that you be able to quickly hear watches and warnings. There is no need to panic, be scared, or be anxious over this. We are VERY cognizant of the fact that people in our area have elevated storm anxiety after the recent tornado outbreak that happened here earlier this month, as well as our area’s overall history with severe weather anyway. Just have your severe weather plans in place, make sure you don’t disconnect from weather information over the weekend and keep checking back for updates, and be ready to act if warnings are issued… and we’ll all get through it together just fine! Above, with our FREE Tennessee Valley Weather App brought to you by your neighborhood QuikMart stores, and our FREE smart TV apps and YouTube channel, are great ways you can stay in touch with us for updated weather information, including having multiple ways of being able to watch our live streaming weather coverage should that become necessary!

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