Potentially significant severe weather threat for this afternoon. A few strong tornadoes possible.
While we appreciate your viewership every day through the year, there are only a few days here and there where we really urge you to pay careful attention to the information that we provide and stay plugged into weather updates throughout the day. Today happens to be one of those days. We have been talking about the potential for strong to severe thunderstorms, including a tornado threat, in the forecast for a full week now. Over the past couple of days, things have begun to look a bit more substantial.
The latest outlook update from the Storm Prediction Center maintains an elevated Level 3 of 5 risk of severe storms for today across the entire viewing area of southern middle Tennessee, north Alabama, and northeast Mississippi. Based on data we have seen overnight, and radar real-time trends supporting that model data having a good handle on things, it wouldn't shock us if a good portion of our area is possibly upgraded to a Level 4 risk at some point during morning updates.
All threat "types" are possible today, but this isn't a marginal or lower-end type of risk. It's not some widespread earth-shattering tornado outbreak either, but this is a potentially significant and serious severe weather situation. The tornado threat today is significant. Model data has consistently painted the picture of multiple supercell storms across the area later today in an environment very favorable for tornado production. Because of the wind shear in the lowest parts of the atmosphere trending stronger as we've gotten closer, combine with how muggy and unstable the air mass will be, there could be a few strong potentially long-track type tornadoes later today. These are the tornadoes that do EF2+ damage and stay on the ground for a significant amount of time. It's not a guarantee that we will see them, but there is an elevated threat of that happening, and we may see one, two, or three of that type of tornado within our viewing area or very close by. In addition to the tornado threat, storms will be capable of producing damaging straight-line winds that may be as high as 50-70 mph in a few places. While it's not as elevated of a threat, a few storms may also produce quarter to half dollar size hail. And, not any less important, with all the heavy rain we've had overnight and additional storms later today, there may be some localized areas of flooding and flash flooding.
The overall timeline for the main severe weather threat across the area later today runs roughly from about Noon to 8:00 PM. It won't storm that entire time in any location, but during the timeframes shown on the timeline map graphic above, there may be individual/scattered supercell storms that will be capable of producing the threats we talked about above.
Here's the "Futurecast" breakdown with the HRRR model. While it hasn't been absolutely perfect, it has had an overall good handle on the situation. Through the mid morning hours, it still appears that most all of the thunderstorm activity stays off to our northwest over northern and middle Tennessee. We can't rule out a few isolated showers or even a thunderstorm this morning, but it's looking more like we will be mostly quiet across the area until the main event starts to take shape later today.
As we head into the late morning and midday, temperatures start warming into the upper 60s and lower 70s as we get a stronger southerly wind and we see a few breaks of sunshine in the cloud cover. This, combined with dewpoints climbing well into the mid or possibly upper 60s, will make the atmosphere primed for thunderstorm development. In addition, winds will change direction sharply from southerly at the surface to more westerly in the mid-levels of the atmosphere, and they will increase in speed rapidly with height from the ground up. This vertical wind shear will be very favorable for storms to rotate later today.
By midday or the early afternoon, rapid development of scattered supercell thunderstorms will begin to happen over north Mississippi into western Tennessee. These look to move quickly into our area during the early to mid afternoon and begin to mature in intensity and organization as they do. Ahead of those, the model is also hinting at the potential for a few additional supercells to possibly form out ahead of the ones back to the west along the front. Regardless of whether that's able to happen or not, supercells in either regime will be capable of a few strong long-track tornadoes.
These intense thunderstorms will continue across southern middle Tennessee and north Alabama into the late afternoon to early evening hours. As we work toward 7:00-8:00, it looks like the stronger thunderstorms shift eastward out of our area as the cold front moves in, but there may still be occasional heavy downpours of rain and rumbles of thunder into the late evening, even after the severe storm threat ends.
It is critical that you pay close attention to weather information today and be in a position to hear watches and warnings. We have a variety of ways, shown above, that you can stay in touch with us for reliable, updated severe weather information. Also, if you have friends or family that live in the area and you think they may not be aware of the storm threat today, send them a text or message or give them a call and tell them that there's a severe storm and tornado threat and they need to pay attention to weather today. We have learned from social science research after major tornado events that one big way people hear that bad weather is coming is by being notified by friends, family, and other people that they trust in their personal lives. You can be a hero by sharing urgent weather information today. You just might save the life of the person you notify!
In addition to being aware of information, you have to have a safety plan in place ahead of time so that you know where you will go to shelter if a tornado warning or severe thunderstorm warning is issued for your area. Above are some helpful guidelines you can use to lead you into picking the shelter location you will take advantage of if you are threatened by severe weather. In addition, we urge that you protect your head and neck with something sturdy when you are in your safe place. We have learned over the years that the majority of tornado fatalities happen from blunt force trauma to the head and neck areas. Protecting your head and neck with something sturdy can reduce your risk of death or injury in the rare but unfortunate event you are directly struck by a tornado. A simple $10 bicycle helmet can safe your life! It is also a good idea to wear closed-toe hard sole shoes in the event you have to walk across tornado debris to get help, to protect your feet from being injured by things like broken glass, boards, sharp pieces of metal, nails, etc. We also recommend that you have a little squeezable air horn or a whistle with you in your shelter location so that you can call for help and first responders can locate you faster in the rare event your home is hit by a tornado and you may be trapped under debris.
Today is a critical weather day, and you must pay attention, but there is no reason to be scared. If you are prepared ahead of time and you pay attention and act quickly if a warning is issued, you will be fine in almost every circumstance. The entire Tennessee Valley Weather Team will be here later today to provide live team coverage for any warnings that may be issued as the severe weather threat unfolds!