nrgjeff

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.

Oh the storm from The Day After Tomorrow sinking south - like the stock market! In sports, the WWE chair rematch is this weekend! KU at K-State is on CBS Saturday!

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?

He's wrong. Looking for attention. I don't see anyone by that name with credentials on Linked In. Currently the Milankovitch Cycles approximately cancel out each other. That's why Climate Science can more reliably zero in on the solar cycle and Carbon. The divergence is startling. Sun is sleeping; temps and CO2 continue up; and previously, they had always all 3 been in lock step.

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.

Above agrees with consensus on the Solar Forecast too. But if the Contrarian verifies, we already had our minimum. Head over to the Climate Change threads.

AMS paper from U. Maryland has a contrarian view we may be heading into a major / active solar cycle. Hypothesis is solar storms dragged out cycle 23. This cycle 24 has been a little short in time duration and solar storms. Getting ready for 25 to roar out of the gates strong. Endless warm winters! Again it's just a contrarian hypothesis. But it would mesh with 2012 going into a warm 2012-13 winter. If anything can go wrong...

Cold core surprise is possible in the Mid South still. Lows are stacked, which is helpful for that type of deal. However cold core is not my wheelhouse. Wake me up in April. Hopefully after Kansas wins the NCAA Tourney in ATL.

Yes those charts are not bad for winter. I was whining about spring severe. That'd work next winter for me.

Hope that's wrong. Totally backwards vs severe favorable TNI.

Hopefully we can avoid Death Nina SER. Japan model isn’t too bad. Most of the cool is south of the Equator. Is the PDO trying to take a breather? Better be after spring cause warm off West Coast makes severe season bo-ring! Now, that look could be nice next winter if the central north-PAC keeps cooling.

Well that would suck the life out of severe. I place my order for cooler weather central tropical Pac. Keep warm east. TNI boom!

I'm ready to see that MDT Red on the SPC charts instead of the WPC charts. Can it just be April yet? 12Z QPF progs are not quite as bad East, but still there Mid-Tenn. Trouble there is double whammy of daytime rain and then the squall line.

We got almost an inch more overnight. Apparently it all ran off. @dwagner88 was I seeing things or the creek was almost up to the bridge by Food City Jenkins and EB Rd?

MRX rightly is/has been more concerned about flooding. SPC has caved, lol. OK seriously, they did not cave. Shorter Term data not available or reliable at Day 4 shows the problems with the set-up now as we move in to Day 2. It's too damn warm at the mid-levels. Oh this wind field would be amazing with April or even March surface temps. Winds with height turn almost 45 deg. Usually Dixie has about 30 deg. Rooted supercells would spin up in a hurry, but... CAPE is hard to come by. They talk about low-CAPE high shear events. This is almost NO CAPE. Looks like skinny cape above 700 mb and questionable if any below. Lack of low-level CAPE juxtaposed (vertically) with low-level turning is a deal breaker. So, I have zero interest in chasing. I'm not really even worried about severe at home. I will be peacefully relaxing and watching Kansas at West Virginia. Uh, actually I'll probably be barking at my TV, lol! Actually the ESPN crooks put it on + which I boycott. OK, hope for severe!

Rare High Risk and large Moderate Risk of flooding is quite significant for the South. Due to the high impact of this event, please share with your fiends on social media. Make sure the graphic comes up on the post. Date it and make it public too. (just change back to friends your next post.) I went through Thursday, though the High is through Tuesday. This is going to be bad from rivers down to streams and low areas.

Lookout Valley west of Chattanooga, flooding on I-24 per Covenant Transport Met. I-24 was closed as of 3pm Eastern Wednesday.

Enhanced risk for central Mississippi into northwest Alabama! Well Dixie has a funny idea of how to do an overnight rave. Jokes aside, I'd ditch the hatched but 10% might be OK. I'd introduce 30% wind though. But the HRRR! But the SFO run? OK back to weather. Both versions of the NAM temper things compared to the HRRR. NAM looks believable given all the cloud cover. However the marine warm sector has made it well north in Mississippi. North Alabama is still conditional on precip. I actually like the wind fields not pegged out, just seasonably strong. However the low level CAPE lacks. Don't take much at night in Dixie, but it needs to be more than 50. LI looks good because it is above the warm layer aloft. Figure storms can root for a couple Mississippi tornadoes this afternoon. Alabama might get to sleep well with just wind if it does not destabilize in the low levels. Believe the sounding is a bigger problem than upper level wind directions relative to the boundaries. It's a quasi-lifting boundary not a CF in the risk area. Either way, I think it's mainly wind. 2pm Central Update: South Mississippi supercell rooting on the marine later warm front. Other cells coming out of Louisiana may root in Mississippi.

An even bigger version around the Smokies. If south or southeast low level winds accelerate around mountains it would enhance low level inflow. Then farther off the ground south to southwest winds could be guided to turn with height due to the direction of the Valley. I'm just speculating on a hypothesis. Similar debate is ongoing for central Oklahoma (Moore/Norman) and the southeast facing Canadian River Valley. That's low levels only of course. The Plains can take care of its own mid-levels. In both cases it is hard to prove causation, but correlation is notable. They have tried to model the OK case.

So up there you get snow and tornadoes! Jealous, haha I wonder if low level winds whip around the ridge southeast of town. Accelerate a bit per Bernoulli effect? And a little farther off the ground I wonder if ridges nudge winds a little veered relative to below. On the other hand it could be random luck.

Questions remain in Alabama due to morning rain on Saturday. Euro has consistently hammered Mississippi and the GFS has now slowed down to do the same. NAM going nearly unidirectional upstairs is a real party pooper for fans of intense severe weather though. Saturday is still the back half of the NAM (as of Thursday writing) where NAM accuracy falls off. However the accuracy issue is usually on mesoscale details. Upper wind fields is a larger scale issue. I'm afraid the GFS/Euro will trend toward the semi-unidirectional NAM. Sure it has helicity off the charts, but that is mostly speed shear. Turning is meh on the NAM. It would be a strong but sloppy line. Now the GFS and Euro (globals) both still have a classic winter Dixie outbreak. Globals start turning 700 mb wind, with 500 mb southwest or better. NAM has 700 mb barely west of south and 500 mb still SSW. They all have a mess at 200 mb, but the globals have enough turning up to 500 mb for a lot of severe wx and some tornadoes. Plus they all have robust LLJs. Instability is marginal, but that is normal in winter severe weather. Tonight or Friday morning, one could check fcst soundings for where that instability lies Saturday; low level or mid-level. If low level (just a few thousand ft AGL) it only takes a few hundred CAPE for severe. If mid-level only it's tough to light the candle. Such mesoscale detail isn't clear until about a day to 36 hours ahead. If everything comes together, one would expect that secondary warm front, originating from the Gulf Coast front, to lift north of I-20 or even US-82. Worst action would be from there south. Otherwise it's a sloppy rain-out except down on the Gulf Coast. Most of this was copied from my Tennessee Valley post. However it looks like the worst of it will be this Southeast Region, because of central/southern Mississippi and Alabama. Even there it could underachieve if the NAM is right.

Yes at one point Alabama looked capped on the Euro following stabilizing Friday night rain. Euro has consistently hammered Mississippi Saturday. I'm less concerned about caps now. NAM going nearly unidirectional upstairs is a real party pooper for fans of intense severe weather though. Saturday is still the back half of the NAM (as of Thursday writing) where NAM accuracy falls off. However the accuracy issue is usually on mesoscale details. Upper wind fields is a larger scale issue. I'm afraid the GFS/Euro will trend toward the semi-unidirectional NAM. Sure it has helicity off the charts, but that is mostly speed shear. Turning is meh on the NAM. It would be a strong but sloppy line. Now the GFS and Euro both still have a classic winter Dixie outbreak. Still sloppy, but it's relative down here. GFS/Euro start turning 700 mb wind, with 500 mb southwest or better. NAM has 700 mb barely west of south and 500 mb still SSW. They all have a mess at 200 mb, but the GFS/Euro have enough turning up to 500 mb for a lot of severe wx and some tornadoes. Plus they all have robust LLJs. Instability is marginal, but that is normal in winter severe weather. Tonight or Friday morning, one could check fcst soundings for where that instability lies Saturday; low level or mid-level. If low level (just a few thousand ft AGL) it only takes a few hundred CAPE for severe. If mid-level only it's tough to light the candle. Such mesoscale detail isn't clear until about a day to 36 hours ahead. If everything comes together, one would expect that secondary warm front originating from the Gulf Coast front. Worst action would be from there south. Otherwise it's a sloppy rain-out and I'm watching college basketball all day Saturday.