2024 Tornado Season

[WeatherArc]

Hi everyone, new topic for the 2024 US tornado season.

Yesterday the first us tornado of the year struck Fort Lauderdale in southern Florida likely causing EF0-EF1 damage.

2024 will be an interesting year, looking ahead we seem to stay in EL Nino till around March/April before transitioning into a neutral state by May, could even be in a La Nina by the end of June, this will have a large impact on severe weather positioning within the US. Many believe the US will have a close to average tornado year with the most tornadoes being either in the southern plains or the deep south depending on jet positioning.

 

Something i dont like at the moment is the state of drought over the US southwest, especially New Mexico. This drought will lead to a stronger EML, could be a problem for any outbreaks across the plains, however outbreaks within the deep south do seem to benefit from stronger EMLs. 

Andrew Shearer on twitter has a good thread on predictions for the season, predicting above average for south east but below for the plains.

On the other hand, Reed Timmer believes the southern plains will be more active.

Regardless, will be interesting to see how the season plays out, if that drought can be slightly relieved ill be much more confident in an above average plains season.

 

 

Anyways, it does seem like the first potential significant outbreak of the season is setting up across the coast of Louisiana, Mississippi, Alabama and the Florida panhandle. The NWS SPC has issued an enhanced risk with a 10% hatched tornado risk area and a 30% hatched wind risk.

The spc discussion mentions a further upgrade to probabilities should confidence increase, however questions about storm mode, temperatures, dewpoints, low level lapse rates and morning convection still remain.

A QLCS with significant wind gusts is very likely with the potential for rare strong QLCS tornadoes. If discrete supercells are able to sustain themselves then a violent tornado cannot be ruled out.

The Helicity across the environment is insane even for second season outbreaks, widely 600+ across warm sector.

Low level jet absolutely cranking, 90 knots Bulk shear also very high. Anyone chasing storms will likely have only one choice, storm motion will be very quick, pretty impossible to catch up to. 

The only good thing is the warm sector will be relatively small. Very lucky this isnt March or April, this would of gone high risk. 

Profile taken from near Houma, Louisiana. Demonstrates the low floor, high ceiling of this event. On the one hand a saturated profile with unfavourable LLLRs  will decrease tornado chances, on the other an insanely good hodograph combined with 700+!!! effective SRH. Knowing that the NAM 3km underdoes surface temps and other models do seem to struggle with winter environments I am concerned about a potential significant outbreak. The deciding factor will likely be morning convection and how it affects the environment. 

Environment continues throughout the night, these are 6am EST soundings from near the Florida Panhandle border. 874 effective helicity is just beyond insane, last time i saw that much was the April 27th 2011 super outbreak, thankfully its winter and the warm sector is very small. Still with soundings like these QLCS tornadoes are very likely, any embedded supercell needs to be watched.

Something that keeps standing out to me is the high 3cape levels, we know that strong 3cape helps efficiently tilt any spin (look at the profiles for the tornado in Manchester a few weeks back) having 3cape in excess of 100 in this sort of environment with this much shear is going to be a big time problem. 

[WeatherArc]

HRRR has best shear separated from the warm sector, still a tornadic environment but less severe. 

[WeatherArc]

This is the area forecast from the NWS office in Mobile, Alabama regarding Monday nights severe risk. 

 

Where to begin. Probably with the fact that with the current trends, we have leaned towards higher confidence in an extremely high impact event for our area. Very strong winds, potentially moderate coastal flooding, high marine impacts and the potential for a significant severe thunderstorm event including damaging winds and potentially a couple significant (EF-2+) tornadoes. Honestly when you put all the potential impacts together this could be one of the more impactful non- tropical systems we ever had. Take this system seriously! Synoptic Overview...A rather potent upper low will eject into the Ohio River valley Monday into Tuesday night. The impressive nature of this system continues to be represented within ensemble guidance with 500 Mb heights at a climatological min within the ECMWF, meaning this is an anomalously deep low. With anomalously deep lows usually come very strong jet dynamics and right now looking at a 110 to 120 knot jet streak developing around the base of the upper low late Monday night into early Tuesday morning. Little further down a powerful 70 to 80 knot 850 mb jet will develop over our area during the same time and unfortunately trends within the higher resolution guidance have even hinted at increasing to 85+ knots. This is relatively rare territory even in some of our more impactful events. At the surface, these intense dynamics will allow for a powerful surface low to deepen into the upper 980s as it lifts across northeastern Arkansas. Expect rain to likely begin Monday afternoon as the synoptic warm front lifts northward and persisting throughout the overnight hours. Rain may become intermittent for a brief period before the final line of storms pushes through early Tuesday morning likely clearing out as we approach the noon Tuesday timeframe. Given how dynamic this system is we expect a plethora of hazards to come.

Severe...Unfortunately, things trended the wrong way for us amongst the high resolution guidance and the makings of a significant severe thunderstorm threat appears on our doorstep. As mentioned in yesterdays afd, extreme environments tend to end in extreme results and the expected environment is quickly trending towards extreme. Going into yesterday the limiting factor was the instability. As worried, the proximity to rich Gulf Moisture coupled with the intense low level wind field should have no issued working instability inland across our area as the marine boundary lifts northward. All the high resolution guidance has around 1000 J/KG of MLCape making its way to the highway 84 corridor with some guidance hinting at near 2000 J/KG near the I-10 corridor and has trended upward with time. Not great Bob, when that was suppose to be the limiting factor. On top of the instability the shear will be ludicrous with that 80 knot LLJ. 0-1 KM SRH values in the warm sector are hovering around the 500 to 600 m2/s2 with insane low level curvature and high streamwise component. It would be immature to not at least mention that sometimes these shear environments can be too much especially with lower amounts of instability much like last years; however, intense jet dynamics in the right entrance region of the upper jet will likely overcome all of those issues. Expect two rounds of severe weather to be possible with both capable of significant severe. The first round is a little more conditional as instability and synoptic ascent will be more limited compared to round two. However, this round will be along the lifting marine boundary around midnight. This will likely involve embedded supercells lifting with the boundary leading to the potential for damaging winds and tornadoes. Given the shear environment and the boundary, a strong tornado cannot be ruled out. Then the real show arrives shortly after and persists through the overnight in the form of a rather strong QLCS. This heavily forced squall line will only intensify as the upper jet overspreads and the LLJ increases. The combination of strong kinematics and low level instability with 0-3km cape values likely approaching 100k/kg or more will support strong vertical stretching in a incredibly rich vorticity environment. QLCS tornadoes will likely be common with this line including the potential for a few strong QLCS tornadoes (EF-2+). Along with the tornadoes, strong damaging winds will also be likely with wind gusts in excess of 70 mph given 850 and 925 mb winds will already be high. This has the potential to be a rather intense severe event occurring overnight. Be sure to continue to stay updated and have multiple ways to receive warnings that are battery operated and charged as power may go out well before severe thunderstorms arrive.

[WeatherArc]

 

[weatherobsuk]

A tornado moved through central Fort Lauderdale, FL on Saturday causing damage to properties & utility lines but no reported injuries.

 

[WeatherArc]

Yikes, that's a massive cape uptrend. 

Lets hope this environment doesn't translate eastward. 

Not sure i believe my eyes here, 225 3cape is extremely high, even for high cape scenarios. Any supercell that can tap both into this and the 700+ effective helicity will become a major problem.  

[WeatherArc]

 

[WeatherArc]

Vince on a powerful cell just north of New Orleans, CG activity has rapidly increased over last 15 mins, hooking on radar. Also has started to become a right mover.

 

Edited January 8 by WeatherArc

[WeatherArc]

Observed Hodograph from New Orleans is just downright crazy, one for the record books.

Luckily its in stable air, can only imagine what would of happened had that warm front been further north.

We are still at the start of this event, peak tornado activity will likely be past midnight (5-7am for us)

The NWS office in Mobile Alabama has issued another statement

Edited January 9 by WeatherArc

[WeatherArc]

We now have a day 3 enhanced risk for much of the same area as the outbreak on Monday.

Per SPC-Severe thunderstorms, with potential to produce high winds and a few strong tornadoes, are possible across parts of the Southeast Friday through Friday evening. ...Discussion... Models continue to indicate that strong cyclogenesis will proceed Friday across the Mississippi Valley through Atlantic Seaboard, as a vigorous supporting short wave trough pivots northeast of the southern Great Plains. It still appears that the center of the growing cyclone will undergo a period of very rapid deepening across the lower Ohio Valley during the day, perhaps with minimum surface pressures falling in excess of 15 mb in 12 hours, before continuing to deepen while migrating northeastward into the lower Great Lakes region by late Friday night. Associated strengthening of deep-layer wind fields is forecast to include a developing swath of 90-120+ kt southwesterly flow at 500 mb across the lower Mississippi Valley through portions of the Northeast and Mid Atlantic by the end of the period. In the 850-700 mb layer, 50-90 kt south to southwesterly flow is generally forecast to overspread the inland advancing warm sector. There remains some uncertainty just how expansive of an unstable warm sector may develop, with perhaps low-level warming and moistening becoming sufficient for weak boundary-layer destabilization northeast of the lower Mississippi Valley through parts of the Tennessee and lower Ohio Valleys during the day. More substantive low-level moistening seems probable off the north central/northeastern Gulf of Mexico, into the eastern Gulf through southern Atlantic Coast states. It appears that this may remain south of the mid-level cold pool, with relatively warm layers aloft, even in advance of mid-level subsidence warming nosing east-northeastward across coastal areas, possibly inhibiting destabilization. However, strong to severe thunderstorm development initiating Thursday night across the southeastern Great Plains into lower Mississippi Valley may spread east/northeast of the Mississippi River Friday morning, before perhaps weakening. Thereafter, it appears that a corridor of stronger surface pressure falls will develop near the Southeastern Piedmont, from Alabama through the Carolinas, Friday afternoon into Friday evening. Near the southern periphery of the mid-level height falls, this might become the primary focus for organized storm development. Otherwise, models suggest that a pre-frontal dryline structure may develop across east central/southeastern Alabama during the mid to late afternoon, before surging across central Georgia into the Carolinas by late Friday evening. Although storm mode remains uncertain, there is concern that this environment may support and maintain discrete supercell development with a risk for strong tornadoes. Otherwise, the evolution of at least a small organized cluster might also be possible, accompanied by potential for very strong and damaging convective gusts.

That trough shape has certainly caught my eye, reminiscent of Rolling Fork last year. 

However, one thing that does stand out is the very progressive nature of the trough/bad timing, will see if it slows down or not in todays runs. 

[WeatherArc]

 

[WeatherArc]

Good points here, recent frontal passages have really pushed out moisture, big questions to do with how far north it can be brought. 

 

[Ben Sainsbury]

After chasing my first time last year, I am back yet again this year for my 2nd chase. Going out for just under two weeks right at the end of May. Fingers crossed we can transition to ENSO-neutral and possibly La Nina as quickly as we can. Latest update suggests ENSO-neutral favored during April-June 2024 (73% chance) which shows a quicker transition to neutral than the previous update.

[WeatherArc]

On 13/01/2024 at 06:38, Ben Sainsbury said:

After chasing my first time last year, I am back yet again this year for my 2nd chase. Going out for just under two weeks right at the end of May. Fingers crossed we can transition to ENSO-neutral and possibly La Nina as quickly as we can. Latest update suggests ENSO-neutral favored during April-June 2024 (73% chance) which shows a quicker transition to neutral than the previous update.

Good luck out there! End of Mays defo the play, seen lots of posts that El Nino seems to be going faster than predicted. Hopefully the drought over the desert southwest also fades over next few months.

[WeatherArc]

Some very notable analogues within those six years, 2010 and especially 2016 standout

Looking like this could be a good year for plains tornadoes.

Edited January 25 by WeatherArc

[MikeUpjohn]

Out from 23rd May through 8th June. Hoping for a good year too! 3 days of road tripping from San Antonio to Denver to meet WeatherHolidays Tour 3 for the storm chasing. And I can't help but notice that road trip takes us across tornado alley to get to Denver too

[WeatherArc]

Tornadoes aside I cant wait to see these things again, plains storms are something different 

[WeatherArc]

Another very interesting chart here of precip anomaly for spring from strong El Nino to strong La Nina.

Kansas really stands out to me here, after many years of below average tornadoes this could finally be its above average year. Two bullseyes here, one in south west Dixie alley and the other across the plains, in line with Reeds prediction of Oklahoma, Kansas and Nebraska having an above average year while places like Ohio and Iowa will struggle. 

Can really see a good comparison with 2016 now, looking at Hanks vid the tornadoes on it seem to be primarily in Kansas, interesting few months ahead!

[WeatherArc]

The 2% tornado risk in Texas today is defo delivering! 

Nothing like a February Cold Core to start the plains season off. 

Edited February 3 by WeatherArc

[WeatherArc]

Looking at another potential cold core event tomorrow,  this time in Iowa and Illinois. Recent CAM runs have upgraded the moisture, really starting to get my attention now.

 

 

 

The 3cape values have got my attention here, if a storm can fire it will have likely 130+ 3cape to tap into, values like that combined with the shear will produce spinny things. Lapse rates are also incredibly good, in past events in the deep south lapse rates (esp LLLR) have been very poor and led to a very messy mode, not this time. 

Cloud cover shows a lovely dry punch, dont think morning convection is going to be an issue here plus the abundant clear skies will allow instability to further build.  

The extremely cold temps aloft are also helping LR and instability.

The only questions right now seem to be with whether storms actually fire, CAMS seem to be divided on this right now.

RRFS shows 2-3 discrete cells firing along the Iowa Illinois border at around 22z

HRRR struggles to fire any cells in Iowa/Illinois but does eventually fire a few discrete cells in Wisconsin at 23z

This event is going to be finely balanced, surface temps too warm and overmixing occurs, lowering moisture levels and making any storm that fires elevated. Surface temps too low and its likely nothing will fire at all, interesting 24 hours of model/nowcasting ahead. 

Edited February 7 by WeatherArc

[WeatherArc]

Yeah, tonight's gonna be interesting.

[WeatherArc]

PDS Warning, a large damaging tornado is on the ground, NWS reporting complete destruction of homes possible, everyone in this warning needs to be underground now. 

[WeatherArc]

Major home damage on vinces stream

 

[WeatherArc]

Town of Albion about to take direct hit, strong tornado still ongoing with visible power flashes on vinces stream

 

[WeatherArc]