2/24/07 FCST: OH/KY/TN/IA/KS/MO/TX/LA/OK/IL/AR

Models are painting an ominous picture for this coming weekend. The EC/GFS/and a few others have been showing this system for a few days now. The consistency has been amazing. The latest EC deepens a low from the 980s into the 970s as it moves from OK and Kansas into Iowa next Saturday. Models are showing dew points well into the sixties along the Gulf Coast into the Tennessee Valley. Dewpoints at or near sixty all the way into Illinois and Indiana.

The latest GFS is showing 80 knot 850 mb wind fields across KY, IL, IN, and Ohio next Saturday and Saturday Night. 500mb wind max of 140+ knot winds as well.

It appears that we "could" have ourselves an unusual February outbreak across portions of the Missouri and Ohio Valleys southward into the Tennessee Valley. If the models are correct then this could be one for the books.

Long way off still but right now it appears that areas from Arkansas into Missouri and Illinois and then eastward into Kentucky, Tennessee, and Ohio could have severe thunderstorms with tornadoes. Storm motion would prob be around 50 knots or greater. Fast moving supercells/squall line/high grad winds as well.

This will be one to watch.

EC
http://www.usawx.com/1eca.gif
 
Last edited by a moderator:
I guess I'm not seeing what would make me consider this, potentially "one for the books." You're talking a week out, so yes, things can change. Perhaps something by the end of this week towards the gulf states, but yeah, it's a long way out still. I expect that after the past two years of extreme weather in that area, the lower Ohio and Tennessee valleys will be more weather-aware. At least I hope so!
 
I'm only posting this here because I've seen several threads in the past week that needed minor correction:

Stormtrack Rules said:
(6) When you start a thread, use the following subject format:
date type: geographic area
For example:
3/7/06 REPORTS: TX/OK Panhandle
Dates must be in MM/DD/YY format (the U.S. standard).
Geographic areas must define one or more entire states... (GOOD: OK, AR/TN, Nebraska) (BAD: Gulf Coast, SE U.S.)

(9) Chase topics spanning multiple or ambiguous dates are prohibited, such as "FCST: This Weekend". Map Room is chronologically organized and is dependent on exact dates. Pick the most representative calendar date and post your message there. Commit to a date, and if it changes you can always move to another thread or start a new one.
--> SPECIAL RULES: Mandatory reading!

Key points: Each thread may only pertain to a single day, and specific states must be listed. As has been the case in the past, "long-term forecasts" are allowed in Weather and Chasing (typically, these are events that are >7 days in the future, making them quite speculative and making it difficult to pin down exact date(s) and locations).

We relaxed the rules in order to deal with the winter weather systems of the past few months. As we head into spring, however, please do what you can to ensure posts and threads are compliant with the rules. Again, I'm not intentionally pointing out Beau, as I've seen this a few times in the past week. Just a friendly reminder before the "real" chase season heats up through the next couple of months :)
 
I guess I'm not seeing what would make me consider this, potentially "one for the books." You're talking a week out, so yes, things can change. Perhaps something by the end of this week towards the gulf states, but yeah, it's a long way out still. I expect that after the past two years of extreme weather in that area, the lower Ohio and Tennessee valleys will be more weather-aware. At least I hope so!

Maybe it's the forecasted deep moisture available for it, or the insane negative tilt with strong wind fields at all levels, or the insane sfc low(not sure what one is looking for if they can't see what it might be with this one). I think anyone that can read a calendar can tell how far away it is. Maybe this should be a rule to the forecast section, no need to state it is such and such days out as a forecast. If anything isn't informing, but always bothered to be mentioned, that would be it.

For many runs this system has been out there in some form or another around those two days. It's probably safe to say at this point that it will at least be there. If it is too far out for you to talk about it, it's pretty simple.

I agree with Beau, this is one to watch. Can't ask for a lot more in February. ECMWF this morning(last night's 0z run) showing a sub-980 low in IA following a couple days of return flow off the gulf. Coupled upper jet structure over the southern states.

(by the way I think the date needs to be the 24th....though the 23rd will likely be game to)
 
Last edited by a moderator:
I tried last night to change the title to the 24th only. I am not sure how to change a title though. It should read 24th though. :) Also the area covered that I had is not listed correctly - again a mod needs to change it to MO/AR/IL/IN/KY/TN.

Not sure why it was all changed like it is now. The date and area is totally wrong.

Thanks
 
Last edited by a moderator:
This should translate into a healthy squall line for the I-10 corridor from Houston, all the way to my location in Jacksonville,FL. I honestly hope to see it, because it isnt supposed to be this cold in Feb. in JAX, 18 degrees yesterday morning at Cecil Field, 23(a record) at JAX Int'l and 29 here at NAS Jacksonville/Towers Field. This could be a sign that this spring could be a rough severe wx season.
 
Morning data continues to show a powerful low moving through Missouri and into Illinois next Saturday Night and Sunday. GFS is a tad further south with the low. It does put IL and IN in the warm sector during the day on Sunday. Cross section from Shreveport to Northern Indiana shows very strong wind fields and turning of the winds across IL/IN.

http://www.usawx.com/crosssectionfeb18thimage.gif

The low deepens to the 980s on the GFS as it moves through the Missouri Valley. The Storm Prediction Center has painted an area across the Mississippi and Tennessee Valleys with the potential of a "significant" outbreak. Still a day six or seven event...so a lot of things can change. Model consistency has been amazing.

Taken at face value this would be a chase day across Illinois and Indiana. Storms would be racing along though...likely at speeds of 50 mph or greater.
 
2/24/07 FCST: IA/IL/MO/KY/TN/AR/TX/KS/LA/MS Severe Weather

It’s been a long time since I have been in a thread like this.. But it looks like our first severe weather chase in the Midwest may be coming up.. Models are still advertising a strong trough to develop over the western US. On the eastern side of the trough, a strong early season storm system is forecast to move northeastward. Bringing warm temperatures, and plenty of moisture, and nice dynamics will be in place.. What happens when you put these together?? Severe Storms.. No worries in the strength of the system. Moisture is plentiful, and dynamics will be there to support a good event.. Main concerns are timing and location. As is typical of all forecasts past a few days out.... Areas in the warm sector would see the greatest convection threat.. Hence, the more north the system can go, the wider the area would be for severe storms.. Right now, storms appear possible along and south of a DMX to DVN line. In these areas, K, LI, TT, SWEAT, CAPE indices are all supportive of convective development.. While the dynamics aren't as strong in IA IL, areas in Southeast IA, Northeast MO and Western IL will be near a triple point. And should see at least some convection.. Although total potential will be more meager with northern extent. But for now will include a very broad area and just say IA IL MO KY TX OK AR LA TN. Further south, KY TX OK AR LA TN, warming and dynamics should support severe thunderstorm development by mid afternoon Saturday.

All the aforementioned scenario’s are very conditional. All model data outputs are computer generated attm, since the system is not developed yet to actually input real data. But models have been consistent on the track thus far.

Another threat is going to be mixed precip and or heavy snow on the backside of the system.. Which would effect the NW 1/4 of the FCST area. But that can be for another time and another thread.
 
Last edited by a moderator:
12 Z models 150-162 hrs...... GFS takes the system further south.. But shows the system to be negatively tilted to a pretty good amount.... Temp. progs are warmer.. And instibility is stronger, but more confined..
 
Last edited by a moderator:
I agree as an earlier post in other section, Yep these things will be dragracing across the midwest. Surface temps & instibility are key here. We are going out today to get our new portable color tv lol. Wasnt planning that till last week of feb. Although we have new pard, with laptop this season. Will be new for us seeing storm structures as we are mobile. Anyway, this low spells trouble if the other 2 ingredients come together. Only drawback, intercept only....Wont be running SE of any one cell for long.
Kevin
 
Arkansas too, btw.

I think I'm with Jeff and MikeH on all of this - we just started looking at the long ranges this morning and were pretty happy to see a definite transition from the winter-esque patterns we have had since Christmas to a gorgeously over-dynamic, ridiculously fast-moving Pacific trough setup. Welcome to early Spring in the southern Plains/Midwest, folks! :D

The only thing I am comfortable in asserting right now is what I mentioned above, and that the GFS is currently advertising a very powerful trough moving in midweek next week, developing a strong LLJ which is supposedly going to pull relatively decent moisture from comparatively "OK" trajectories up into the eastern southern Plains/Ozarks/Midwest by 0Z Friday, Feb. 23rd. Sometime between the 23rd and 24th of Feb, this powerful system will eject and interact with whatever moisture/associated CAPE it has managed to accrue. As of now the models are showing good CAPE across LA/AR of values to 1500/2000 - which is good 'n' plenty for late February with these dynamics.

Given my geographic position, it stands to reason that I will be watching this system closely and hoping for a possible weekend chase come next weekend.

A thread question; is there any chance of "regionalising" the area listing on the thread title?? Listing ten or more states in a FCST thread's title is a little bewildering when trying to ascertain the general area of interest......not to mention the fact that the state that seems to be at the center of a lot of the forecast SVR (Arkansas) has been shut out of the title completely.

Will remain to watch......

KL
 
Last edited by a moderator:
Granted this setup is still 6 days away so the exact region of interest will change. But it's noteworthy that both the GFS & European Operational have been concistent in showing an intense shortwave ejecting into the Plains Friday night into Saturday. Both generally indicate widespread convection firing ahead of a strong surface low across Eastern Kansas, much of Missouri and as far north as Iowa and as far south as North Texas.

I'm impressed that the GFS (once it got passed the resolution glitches beyond 180 hours) has been showing a large area of 1000j/kg+ CAPE, and 500mb temps near or below -20C. The current GFS would suggest a significant severe weather outbreak across Eastern Kansas and Missouri, while the European is similar but extends things further north into Iowa. Either way they are both quite similar considering it's 6 days out.

The Ensembles support this general scenario as well, by concistently showing an intense surface low track northeast from Kansas to near the Iowa/Missouri/Illinois border during this time for several days now.

At any rate I believe a significant severe weather outbreak will unfold on Saturday across the Southern to Central Plains, namely Kansas, Missouri & Iowa. I'm expecting this to be the first big tornado day of the year. I just hope the system doesn't speed up, puting the tornadoes over non-chaseable terrain. Hopefully it will slow down just a bit and the event will unfold over Central Kansas & Nebraska.

- Jim
 
i'm still a bit skeptical...i mean, just a couple days ago the GFS had this system running along the gulf coast. yet, the models have been fairly consistent from run to run since then. i dont think moisture will be an issue given the ammount of time she will have to pull in warm air from the GOM into the entire warm sector. The speed and size of the wind field, i believe, is the most ominous part of the entire system. these storms could be moving 50-70mph! the next week will be very fun and interesting to watch and see how this system evolves.
 
Early season storm systems do usually go very fast. They can test a chaser to the core (if one can even catch the storm).

That said, I suspect a great deal of grunge and low visibility systems will compound the severe threat. This may be a powerful early season storm but as is often the case will be a difficult one if one is looking for photogenic or high contrast footage. One will have to be on their toes, either ready to chase after it, move out of the way, or get in the right place at the right time for the shot. It's a ways out, but I too believe this one (as an early pre-guess) will produce low visibility, fast moving tornadic storms somewhere over the Plain states, my guess right now, Missouri-Kansas should be in the hot seat.
 
Last edited by a moderator:
Ahh, finally, a pattern change! Chalk one up up for the fat rodent in Pennsylvania; winter's dance is done, and it is FINALLY spring's turn. And if the models are correct, it will not merely slip in inconspicously, but rather waltz in like a hellbent elephant with a potentially historic and violent fanfare.
As the low develops over northeastern New Mexcio during the day Friday and ejects northeastward through the Central Plains and into the Midwest, it looks like the cold sector of this system is going to blast the Front Range, western High Plains and northern Plains with yet another ferocious blizzard Friday night-Sunday morning. The warm sector will feature a very prolific severe wx and probable tornado outbreak over the eastern portions of the southern/central Plains. It is indeed very exciting to see such a potent system this early in the year. It suggests that this spring, if not this season may attempt to dramatically overcompensate for last year's mediocrity.

But on the other hand, it is quite ominous at the same time, and I am quite concerned about the residents of the eastern sections of the Southern/Central Plains, the Ozarks, the Mid-Mississipi Valley and the Lower Ohio River Valley in the Friday-Saturday timeframe. This is a very powerful system you'd expect to see in mid March, not late February. I don't think most residents outside of the meteorlogical community are going to see this one coming. I mean, who in the general public besides us weather weenies would be thinking 'severe weather' in late February, let alone 'tornadoes'???
Also, these storms are going to be screaming along in excess of 50 mph and possibly as fast as 70 mph ahead of the 100 knot + jet streak, so not only will the rapid motion of the storms make them a difficult chase proposition at best, but will significantly shorten the warning lead times and leave a very narrow time window for residents to seek shelter. I believe that either on Friday or Saturday afternoon, depending on how fast the low ejects, tornadic supercells will erupt across eastern Kansas and Oklahoma as well as western Missouri and Arkansas and then race eastward into 'The Jungle' (the Ozarks & Mid-Mississippi/Lower Ohio Valley) after dark and threaten points farther east well into the early morning hours on Saturday or Sunday.
Not to be a doomsday prophet, but taking into consideration the time of year this system is occuring, the overall extremely volatile atmospheric setup, a forecast strong LLJ which would allow the storms to remain tornadic well after sunset, low storm/tornado visibility due to darkness/topography and recent fatal events during the overnight hours in this area, I believe we will see a significant number of fatalities from this outbreak if it all comes together as forecasted. Having examined recent fatal overnight tornado outbreaks with significant fatalities make me suspect this outbreak will be no different. In fact, due to the lack of severe weather awareness at this time of year and the potential severity of this outbreak, it may possibly be much worse in terms of fatalities.:eek:

We're still five days out and things could change between now and then, but both the concurrency of the recent model runs and my meteorological gut tell me something wicked this way comes. If I lived in Little Rock, Tulsa, Springfield, Kansas City, St. Louis, or Memphis, I'd be paying extremely close attention to the forecasts over the next five to six days. Des Moines/Omaha and Dallas/Fort Worth/Shreveport should take notice as well in case the storm would shift further south or north of its predicted trajectory.
Looks like we could be in for a very rough weekend.:(
 
Last edited by a moderator:
Not to be a doomsday prophet, but taking into consideration the time of year this system is occuring, the overall extremely volatile atmospheric setup, a forecast strong LLJ which would allow the storms to remain tornadic well after sunset, low storm/tornado visibility due to darkness/topography and recent fatal events during the overnight hours in this area, I believe we will see a significant number of fatalities from this outbreak if it all comes together as forecasted. Having examined recent fatal overnight tornado outbreaks with significant fatalities make me suspect this outbreak will be no different. In fact, due to the lack of severe weather awareness at this time of year and the potential severity of this outbreak, it may possibly be much worse in terms of fatalities

I sincerely hope this isn't the case, and although my comments tend to "stir up the stink," I still just don't see this as becoming a dooms-day, end of the world outbreak. Yes, I do see the models just as everyone else, but I'm also going on a little history, climatology, time of year, and overall speed of this system.

Almost a mirror of last year, to me it appears the system will kick out very fast and too far east of the traditional alley, so there goes your good chase terrain - at least traditional chase terrain of years ago. Second, it looks this could be a nocturnal event with screaming squalls throughout the evening. Third, with the recent cold air intrusions all the way to the Gulf, even with several days recovery, I'm still somewhat skeptical on TRUE gulf moisture getting far enough north where the better dynamics are forecast. And finally, limited surface heating due to widespread cloud cover due to streaming moisture ahead of the low. A stratus deck is very typical for these early-season systems with this type of flow and associated moisture overrunning dormant vegetation/terrain.

Again, these are just my thoughts. As stated before, there's nothing more I'd prefer than an active season starting early and giving everyone a great wealth of photogenic storms. All I'm saying is, BEFORE talking about fatalities, widespread tornadoes and an outbreak for the record books, there's more to it than just model forecasts. We've seen a lot of these early systems do the very same thing, so I'll remain skeptical until 1-2 days out.
 
Last edited by a moderator:
I will say this, 6 days out I have rarely seen a storm track take the same one that is indicated. More often then not, the track is *much* different, and dynamics are usually different too. A slight shift right now in the Pacific can change everything. Speaking from experience, we need to really watch this yes, but things rarely pan out exactly as 6 day model runs indicate.

The set up now looks juicy, the proof of all this will be if the runs can MAINTAIN their consistency. If I see one major shift or wobble in model thinking, or they suddenly go all over the dartboard, I'm not counting on any of this to actually pan out. Just my thinking at this time.
 
Almost a mirror of last year, to me it appears the system will kick out very fast and too far east of the traditional alley, so there goes your good chase terrain - at least traditional chase terrain of years ago. Second, it looks this could be a nocturnal event with screaming squalls throughout the evening. Third, with the recent cold air intrusions all the way to the Gulf, even with several days recovery, I'm still somewhat skeptical on TRUE gulf moisture getting far enough north where the better dynamics are forecast. And finally, limited surface heating due to widespread cloud cover due to streaming moisture ahead of the low. A stratus deck is very typical for these early-season systems with this type of flow and associated moisture overrunning dormant vegetation/terrain.


Some very good points there. I think if the system verifies close to the way it looks now, there will still be an outbreak at least in the southern states. Deeper moisture, slower storm speeds, and greater insolation prior to storm development would make this area much more ideal. To the north there'll likely be more linear squalls, and elevated hailers moving at very high speeds. The upper winds down south are more veered too, which is nice. As others have stated, the mid and upper level winds up north are highly backed, so I think supercells are much less likely up there.

Still all early speculation, but it's fun.
 
Almost a mirror of last year, to me it appears the system will kick out very fast and too far east of the traditional alley, so there goes your good chase terrain - at least traditional chase terrain of years ago. Second, it looks this could be a nocturnal event with screaming squalls throughout the evening. Third, with the recent cold air intrusions all the way to the Gulf, even with several days recovery, I'm still somewhat skeptical on TRUE gulf moisture getting far enough north where the better dynamics are forecast. And finally, limited surface heating due to widespread cloud cover due to streaming moisture ahead of the low. A stratus deck is very typical for these early-season systems with this type of flow and associated moisture overrunning dormant vegetation/terrain.

Again, these are just my thoughts. As stated before, there's nothing more I'd prefer than an active season starting early and giving everyone a great wealth of photogenic storms. All I'm saying is, BEFORE talking about fatalities, widespread tornadoes and an outbreak for the record books, there's more to it than just model forecasts. We've seen a lot of these early systems do the very same thing, so I'll remain skeptical until 1-2 days out.

We had systems to even kick out last year? LOL. They all kicked out the same? Guess I don't get how it can mirror a year as a whole. I guess I never thought of the problem being the speed they were kicking out.

Chase terrain. Since when is KS bad chase terrain?

It's going to be nocturnal? I thought it was too far out? To me it looks like it has much more potential to be an early event(like noon).

Cloud cover. It's pretty amazing what can happen in crappy cloud cover when you kick a vortmax out onto the plains like that. But hey it is too early to get specific...or at least I thought it was.

As it is more than model forecasts, it's more than every negative aspect one can post about.

Edit: Oh yeah and moisture. Low Level Jet I hope that is favorable lol. The gulf may have had a recent frontal passage but you have a decent tropical connection there, in advance of the system.
 
Last edited by a moderator:
Mike, your points are well put. We agree on some, disagree on others, and that's the fun of the forecasting. I did post some response to your most recent comments, but moved them to the "Weather and Chasing," as to adhere to ST rules. I'm anxious to see what the models show come 24-48 hours out!
 
Latest GFS run puts the storm much farther east and winds up over the great lakes. Forget consistency, we're back to the playing field with this one as far as GFS goes, folks...
 
I’m thinking very basically about everything. It’s early in the year, we don’t usually see major outbreaks in the southern plains (Keyword usually). While the GFS looks quite impressive, we all know that unless things line up just right, a major outbreak won’t happen. I expect that some key element(s) will be missing. Insufficient heating due to a nice stratus shield, or lack of deep rich moisture are some that come to mind with such early season systems. Some may disagree with me by looking at March 12-13 of last year (correct me if the dates are wrong). But at least we all agree on something right now. “It’s too early to tell” ;) However a nice strong squall line to kick us out of winter will be very welcoming on my part.
 
Having a look through (esp ECMWF output), at this stage, this is how I see it unfolding (albeit with the usual caveats of still being over 120 hours away!).

The strong system approaching the Plains starts affecting the region on Friday as height falls begin to overspread the region, and SSE winds transport Gulf air into the TX/OK region - dry line looks like setting up from SW TX - N Cent KS, with the best forcing appearing to be over the TX P'hndle/SW OK - shear suggests supercells, and with 60+dew points in place, tornadoes also possible. Overnight, squall line starts to take shape.

Saturday - squall line continues east, with some (but at this stage, not impressive) instability ahead of it - however, given the very dynamic set-up and strong shear, tornadoes seem quite likely, from MS/LA northwards towards IL. However, the most chaseable set-up maybe a cold-core type event over E KS/NW MO.

Plenty will change as the week progresses, but at this stage, a rather nasty event seems quite likely.

GFS is somewhat quicker with the progression of the trough - at least the 00Z run was.
 
I found an image that the NWS Springfield had designed and put on their page for the weekend's severe weather. It looks a bit similar to March 12-13 if I recall.

weekend_storms.png
 
This system is surely lacking in some areas as compared to the March 12th event. The plus is that this system is slowing down on the latest runs. The minus is that the mid-upper winds are pretty strongly backed...so would have to rely on very strong low level shear and deep speed shear to get things interesting. Also will have fast storm motions to deal with. Given the forecasts shown on the 06z GFS run, there should not be a problem getting low-topped tornadic supercells to organize...even though a squall line is likely to organize eventually. The target at this point would be between Wichita...KC...Joplin...and Tulsa for Saturday's chase. The surface low track is forecasted to take a Wichita to KC track from Sat. afternoon into the nighttime hours. Now the waiting game starts as to if there will be any other changes or surprises on the 12z runs. I would say Saturday is a green light go at this point for chasing. :)
 
Last edited by a moderator:
Back
Top