nrgjeff

Wednesday night southwest flow apparently washed out any boundary. The veered off onslaught saved us from spinners. Then the 5% East Tenn. Wow it was obvious back around midday Wednesday that's not necessary. Might explain SPC. With all due respect, they've been way too model dependent the last couple seasons. Especially the amped up HRRR.

The good the bad and the ugly. Bad first: Tonight looks like an overnight event. The Good: I don't see enough turning (low or upper level) for a big tornado risk. Wind and hail yes, especially from sups. Instability could cause some gorilla hail Midsouth. Yeah we'll have some sups, but turning wind is not that bad. Helicity forecasts are up due to speed shear, but directional is meh. The Ugly: Forecasting an Outbreak Day 5 Sunday. Who knows? Maybe a Gulf Coast MCS will rescue all of us. I mean, it is Easter! Since we can't chase right now, might as well side with the Public and wish against severe.

It's probably usable NWP, even with some degradation. We been modelling 500 mb for over 50 years. The pattern is obviously quiet upstairs. Chaser be like, fine. Get the garbage pattern over with while we can't go out anyway. No matter what, I'm out of the field through April 30, or later if state level guidance goes longer.

SPC goes with a tornado watch that gets to KATL and all of the southern 'burbs. While the LLJ is a little veered, it is bringing in a moist fetch. Also surface winds are really backed on that retreating boundary. Regarding that LLJ, I've noticed southern Georgia can produce while a little veered off. I think most of the Atlanta metro is OK, some morning rain and the atmo should not recover / destabilize enough to get nasty later. South Georgia could have a day though.

Jonesboro tornado trolled all the Illinois and Iowa chasers. Thankfully nobody was killed, but news says some serious injuries. OK we get a break this week. Probably a good thing. Models saw the East trough last week, and it's in progress now. Next week could get active again. Convection is coming out of the Indian Ocean toward Indonesia (maritime sub-continent). Lead by the ECMWF all models are coming around to a West trough. Euro verbatim favors Plains/Midwest. Getting into April it could go north, south and/or both. I don't have any plan to chase anything beyond 2 hours. Dixie just isn't worth the drive, lol.

Gulf will also help severe season along. LOL the CFC flip flops on ENSO. Ahh, that spring predictability barrier.

Big changes since Sunday. Instead of Ohio River Valley jungle, we now have an outflow boundary in North Alabama and just south of KCHA. Still plenty of failure modes. A. Rain-out B. Veered off C. Capped (too little too late) D. Combo of 2-3 above E. Rather watch sports reruns Early season is prone to failures, which is of course good for the general public. That said I figure ENH is incoming. Obviously if something is close to KCHA I'll take a look. No chase greater than 2 hours though; so, I won't be visiting the chasable northwest Bama area today.

We got throttled March 2012. I've nothing much on this week. Veered off trash. Only turning is in the Ohio River Valley jungle. Back to NCAA Basketball reruns!

I expect Tuesday will get an Outlook on Saturday morning or soon after. Euro remained consistent if not stronger. LLJ is a touch veered, but not like the last two systems. It's fortunately not backed like Super Tuesday either. Upper level winds are a given. Low level theta E (temps/humidity) will be a question. Even with all those caveats, if the Euro holds, one has to think Tuesday gets a 15%.

The Midwest can have it. Dixie had enough heartache for the season.

Link between COVID-19 and weather. Storm chasers enjoy cheap air fare to the Plains. No 14 hour drive! Oh wait, the actual storm chasing days. I forgot about that.

I got distracted watching stocks, lol! But yes, we have a severe weather problem in Tennessee tonight. So the models all have Missouri Boot Heel convection going into Kentucky. All clear? Hell no! Let's do some meteorology. First of all it's not moving northeast. It's moving due east. That'll anchor the boundary farther south than progged. Gee, that never happens. I am hoping the short-wave ejection will push the boundary to the TN/KY border. If not it's in danger of hanging up near I-40. Frankly breaks my heart to type this. Sometimes we science. Sometimes we pray. Anyway, the 850/925 mb charts look more veered than Super Tuesday. Do not expect a repeat. Still, just strong storms disrupt recovery. Psychological damage of just general thunderstorms can't be ignored. Shear will be worse up in Kentucky (or wherever the boundary settles out). Not Super Tuesday, but not a good night either.

Please do. Your local utility will like you. Thoughts are my own, lol! If we can keep air fare low through next winter, I see some Rocky Mountain skiing in the forecast!

Guess we can already go with another blowtorch winter 2020-21. Maybe the SER will be such a beast it keeps severe Midwest and Plains. Flash drought coming to a place near you.

Yes @Calderon is absolutely correct! @PowellVolz that's not a TDS. That is lofted debris carried into the forward flank. Also a sign of a violent tornado. Sure enough OHX finds EF-4 damage. Though the lofted debris signature didn't last as long, it has similarities to the Kansas City tornado last May. Middle Tennessee tornado itself might have lasted longer than the KC one. Have to look back at all that. At any rate, this Tennessee tornado was historical.

European weekly charts are ugly for severe wx the next few weeks. Great Lakes Ridge with Gulf Coast underbelly is replaced with more traditional East Coast ridge. +AO and -PNA spell more Dixie Alley trouble. I'm not rooting for this. Rather postpone to May Plains.

Low CAPE high shear events happen. Wait! This was not exactly that... I'm watching KPAH get the hail treatment about 5pm Monday. Back of my mind I know it's westerly flow aloft over a boundary - but a little early in the season for that set-up. Text my buddy a boundary rider is going off on PAH, but don't think too much about it. Cell weakens, and I start gearing up for Big Monday college basketball on ESPN. Wake up Super Tuesday to Middle Tennessee super tragedy on the news. WTF? Going back to Monday afternoon shear was never in question. I've written here many times, look for westerly flow aloft instead of that SSW flow junk. Nearly 90 degrees of turning was noted. 850 was a little veered, but upstream was deep moisture - count it as backed in Dixie. 925 mb was straight south and both increased going overnight - all forecast ahead of time! Surface of course had the notorious boundary related SRH. CAPE and instability was more complicated. Steep mid-level lapse rates were in place, but low-level CAPE was close to zero. Forecast soundings had the latter improving; but, I'm such a skeptic of those. Normally early season other rain is falling, and it remains stable. Well no rain was falling south of the boundary. Surface chart in retrospect shows an unstable airmass advecting in unfettered. Sure enough it arrived at the boundary in Middle Tennessee. LLJ strengthened. Alas the 2% TOR area was under the gun. CAMs actually had robust storms, but not necessarily a boundary rider beast. Old fashioned meteorology could have provided a more obvious heads up before the evening news. However, credit some local TV Mets for sounding the alarm on the evening news. Still, it's tough to overcome a 1am long-track cyclical damaging tornado. Dixie Alley is just so awful. It's either busted chases, or much much worse. The human suffering down here is cruel. At least the Vols cheered up Tennessee. https://davieswx.blogspot.com/2020/03/march-3-2020-double-digit-death-toll.html excellent article from Davies.

Flash Drought, but still humid AF and AN temps. Yuck!

ERTAF has begun! Cue up, It's the Most Wonderful Time of Year! Agree with them though, it looks benign for a while. Just as well until after the Final Four. Japan satellite shows the two Kelvin waves (MJO pulses) well. Also got a trough trying to dig into central China. Probably get a ton of MJO interference though. Though both sets of weekly forecasts appear on fire with the West trough, devil is in the details. Soft underbelly Deep South hints split flow chaos.

Super Tuesday severe setup is now hampered by sharp divergence between the progressive GFS and slower Euro. Truth may end up in between, but mostly toward the Euro. As for north/south tracking, EC Op surface low is buried in the Deep South. However the vast majority of its EPS (Ensemble) members have surface lows farther north including the Midwest. That's more severe and more heavy rain here. No wind fields analysis since the whole thing is a cluster now. One can imagine the north members have better wind fields. South members are cool rain. Heck now we can't even pick out the day or the place. Tuesday Wednesday or Thursday anywhere from the Delta to the Carolinas; but, probably only one day where everything comes together for severe in just a couple states. Flooding rain is a different story in a different thread.

Last time the Euro won this battle. It's less flooding and less severe. This case I'll punt my love of severe and pray for lower QPF.

ECMWF backed off severe a touch, but seems to have shifted the highest QPF into the heart of TVA. Only good news is that high QPF isn't as high as shown 12 hours ago elsewhere. On the severe side, several EPS ensemble members are more like the previous runs. Low press into the Midwest and severe here. EC Op is frontal overrunning.

Euro weeklies just piled on for a bunch of rain next week. Just awful.

Euro retains at least 30 degrees of turning from 850 to 500 mb, and some runs it's close to 45 degrees. Speed shear is pretty much a given. If that directional shear verifies (tendency to get more uni-directional toward the day) and holds it could be a significant severe weather episode. Probably mostly Deep South though, not really our region. At least south of I-40. I was supposed to give up storm chasing for Lent, to keep me out of early season junk. Hmm, what else?

Tuesday 12Z Euro buys in for Day 8 Mid South. Winds turn enough with height, a new development, and dews are there. However it could fall apart the next 7 days. Either way I expect an active March. Trough in the west and Rockies.