-Springfield, MO Tornado Outbreak, Miss Valley/G'Lakes

[Ed Mahmoud]

Check out the EC forecast of a 40m/s (80 knots!) low level jet!


Big trough just starting to take a bit of a negative tilt...




Its a ways off, but the GFS ensembles also suggest a storm...

[Squarethecircle]

Why is it that I'm never the first person to hear about these things?

Well, the days between now and then should certainly be interesting enough.

[Ed Mahmoud]

Why is it that I'm never the first person to hear about these things?

Well, the days between now and then should certainly be interesting enough.

If (and its a big if) the EC is right, tornadoes might get up to Missouri and Illinois, maybe even Iowa.



Check DonaldSutherland1's thread on temperature anomalies, it'll be almost Spring time warm...

[Cyclone1]

This is gonna be one crazy January.

[Ed Mahmoud]

First 12 hours of the GFS out now, but I gotta work tomorrow...

[Ed Mahmoud]

0Z GFS generally seems supportive of an un-January like severe episode Texas to Illinois a week from Tuesday.

[Ed Mahmoud]

0Z ECMWF shows powerful storm with 60 to 70 knot LLJ from Louisiana to near Chicago late Tuesday next week...



Healthy 500 mb trough




If there is a 60 to 70 knot 850 mb jet, than almost by definition any thunderstorm would have the possibility/probability of severe wind gusts.

6Z GFS at 204 hours looks similar.

Still too soon to be certain, but interesting.

[Ed Mahmoud]

12Z GFS still in the ballpark.


Trough has a bit of a positive tilt, which, in my experience, sometimes seems to result in South Texas becoming capped, but forecast 850 mb flow is mostly from the South.


Looking at my PPV AccuWx 12Z GFS SB Cape, Eastern quarter of Texas and most of Louisiana in excess of 500 Joules/Kg, with the immediate coast over 1000 Joules/Kg.

And Total Totals above 50 cover much of the area between Illinois and the Western Gulf Coast, so even if storms aren't quite surface based North of Texas and Louisiana, there is strong 850 mb to 500 mb instability. While Texas and Louisiana have the best CAPE, 850 mb winds forecast Tuesday afternoon are 30 to 40 knots, not too shabby, but 850 mb winds Arkansas to Illinois are running 50 to 65 knots.

So the GFS is quite similar to the earlier EC runs on a strong low level jet.

[RL3AO]

Wow. Looks like 2008 might start with a bang.

[Ptarmigan]

Some of the biggest tornado outbreaks have occurred in La Nina years. This will be interesting.

[Ed Mahmoud]

Not to toot my own horn, well, maybe just a little, I think I have a pretty good knack as an untrained amateur spotting severe weather out a week away.


Thread from October


That thread got to 32 pages...

[HarlequinBoy]

One of more memorable outbreaks for me personally, occurred in January 1999. Included an F4 into Jackson, TN and and F3 into Little Rock..

[Cyclone1]

Not to toot my own horn, well, maybe just a little, I think I have a pretty good knack as an untrained amateur spotting severe weather out a week away.


Thread from October


That thread got to 32 pages...

Nothing wrong with that. Before I joined Storm2k, I called Barry's formation a good 10 days before it formed, and I did not shut up about it.

Still to this day, as you can see by this post.

[Ed Mahmoud]

0Z GFS still onboard for interesting weather next Tuesday, with added bonus of change to snow in Oklahoma and Texas Panhandle

[Ed Mahmoud]

Storm Prediction Center now has a Day 7/Day 8 risk area identified.

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0330 AM CST TUE JAN 01 2008

VALID 041200Z - 091200Z

...DISCUSSION...

MEDIUM RANGE MODELS CONTINUE TO SUGGEST THE EVOLUTION OF A DEEP
UPPER TROUGH ACROSS THE WRN U.S. BEGINNING LATER THIS WEEKEND. WITH
TIME IT APPEARS BOUNDARY LAYER MODIFICATION OVER THE WRN GULF WILL
PROVE MORE THAN ADEQUATE FOR SIGNIFICANT MOISTENING ACROSS THE SRN
PLAINS/LOWER MS VALLEY REGION. THUNDERSTORMS...SOME OF WHICH WILL
LIKELY BE SEVERE...SHOULD DEVELOP IN ADVANCE OF THIS PROGRESSIVE
UPPER TROUGH BY MONDAY OR TUESDAY...THOUGH SLOWER EJECTION OF UPPER
TROUGH COULD DELAY THE SEVERE THREAT BY A DAY OR SO.

..DARROW.. 01/01/2008

[RL3AO]

I don't like that they are saying "will likely be severe" seven days out. This could be a big outbreak.

[Ed Mahmoud]

Looks like the 12Z GFS progging decent CAPE and shear, although I can see the chance of areas South of I-10 in Texas being capped. Of course, a little cap, enough to prevent premature storm initiation, and produce isolated storms, may be a favorable for severe North of I-10.

[RL3AO]

Looks like some heavy rain in Minnesota. I wish it was snow. We might get 20 inches!

[Ed Mahmoud]

SPC still onboard for a Day 6/Day 7 severe outbreak!

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0333 AM CST WED JAN 02 2008

VALID 051200Z - 101200Z

...DISCUSSION...

TIMING OF MAIN UPPER TROUGH INTO THE MID SECTION OF THE COUNTRY
EARLY NEXT WEEK WILL LARGELY DETERMINE THE SEVERE THUNDERSTORM
POTENTIAL...INITIALLY ACROSS ERN PORTIONS OF THE SRN PLAINS AND THE
LOWER MS VALLEY REGION. ALTHOUGH THE GFS AND ECMWF DIFFER REGARDING
THE EXACT TIME OF TROUGH EJECTION INTO THE PLAINS...BOTH MODELS
REMAIN CONSISTENT WITH THE OVERALL EVOLUTION REGARDING SIGNIFICANT
MOISTENING/DESTABILIZATION ACROSS ERN TX/LA...NWD INTO SRN MO.
STRONG RETURN FLOW...SUSTAINED FOR SEVERAL DAYS AHEAD OF SHARP
FRONTAL BOUNDARY SHOULD ENHANCE ROBUST THUNDERSTORM POTENTIAL
BEGINNING AS EARLY AS MONDAY/TUESDAY.

..DARROW.. 01/02/2008

[Ed Mahmoud]

Well, 12Z GFS shows CAPE at/below 500 J/Kg at 18Z and 0Z next Tuesday afternoon/evening CDT for Texas and Louisiana, and below 250 Joules/Kg in Oklahoma, Arkansas and Missouri.

But I won't give up hope with a healthy trough and a 30 to 40 m/s LLJ in the area. I guess it all depends how quickly the single digit dewpoints that have plagued Southeast Texas like a swarm of locusts can be replaced by modified Gulf air.