KSStorm Blog

The SPC is high­light­ing the poten­tial impact of tomorrow’s storms with a HIGH risk out­look. The only time they’ve done this before (accord­ing to Wikipedia) is Apr 6, 2007. On Apr 7, tor­na­does raked the mid-south, par­tic­u­larly the north sub­urbs of Nashville, killing 13.

Inter­est­ingly, there were no EF-4 or EF-5 tor­na­does in the 3-day out­break from Apr 6–8, and only 7 EF-2 and EF-3’s. Dynam­ics for tomor­row are a com­pletely dif­fer­ent picture.

Inter­est­ing to me as I read the var­i­ous dis­cus­sions is the preva­lence of “the com­put­ers are hav­ing prob­lems mak­ing this as bad an event as the peo­ple believe it will be” in the fore­cast think­ing. Examples:

MANY OF THE MODELS DO NOT DEVELOP NUMEROUS THUNDERSTORMS ALONG THE DRYLINE.

IN SPITE OF THIS...THE MODELS DIMINISH THE CAP ACROSS THE SRN AND CNTRL PLAINS

LATE SATURDAY AFTERNOON SO THIS BRINGS THE MODELS INTO QUESTION.

((SPC Day2 DISCUSSION))

BOTH THE NAM AND GFS ARE HAVING SOME TROUBLE DEVELOPING WIDESPREAD CONVECTION

ALONG THIS BOUNDARY UNTIL MID LEVEL LIFT INCREASES TOWARDS 00Z/SAT...WITH COVERAGE
EXPECTED TO BE MORE SCATTERED IN NATURE UNTIL THEN.((ICT Forecast Discussion))

It almost seems like WFO ICT is dri­ving the bus on this one…not that it’s a bad thing.

FORECAST SOUNDING FOR KICT AT 03Z/SAT LOOKS LIKE THE PROVERBIAL "LOADED GUN"...

WITH SUPERCELLS AND A FEW STRONG TORNADOES LOOKING VERY LIKELY SAT EVENING

FROM KSLN TO KICT. 

((ICT Forecast Discussion))

AFTER COLLABORATION WITH WFOS WICHITA...NORMAN...TOPEKA...TULSA 

AND DODGE CITY...A HIGH RISK WILL BE ISSUED DUE TO THE POTENTIAL 

FOR A HIGH-END LIFE THREATENING EVENT ACROSS THE SRN AND CNTRL PLAINS.

((SPC DAY2 Discussion))

Maybe “dri­ving the bus” is putting it a bit strongly, and I’m pretty sure my friends at WFO ICT would take excep­tion to that char­ac­ter­i­za­tion. But the SPC dis­cus­sion says to me that it would have been a Mod­er­ate risk if they were left to their own means and thoughts. But the peo­ple locally, in ICT and other regional offices, made a per­sua­sive case that tomor­row really will be one of those “oh, crap” days, despite the mod­els hav­ing a prob­lem get­ting storms started.

Here’s the takeaway:

Peo­ple with many years’ expe­ri­ence in fore­cast­ing severe storms on the Kansas plains have every expec­ta­tion that tomorrow’s weather setup will lead to life-threatening severe weather. Their expe­ri­ence and skill is being allowed to over­ride the com­puter mod­els that show slightly less risk.

LISTEN. TO. THEM.

Updated fore­casts for tonight and tomor­row, later in the day.

If you don’t have a weather radio, get one. If you don’t have quick access to a shel­ter UNDERGROUND, get hold of friends who do and make appro­pri­ate arrangements.

A lot of friends out chas­ing today, and if things had set up a bit dif­fer­ently in rela­tion to dis­tance, time, and expense, I’d be out too. With two days of chas­ing to fol­low, I just couldn’t jus­tify it in the end. Time to get some rest and charge up for the weekend!

I’m not lik­ing the mod­els for Sat­ur­day evening right now. At least the NAM. The lat­est run put sur­face winds in the Wichita area more from the south than the south­east, and the curve in the hodo­graph doesn’t start until sev­eral thou­sand feet in the air. That would be more indica­tive of a hail event than a tor­nado out­break. But with two days of storms to affect the mod­els, I’m sure that will change. Not going to put a lot more time into Sat­ur­day at the moment.

Much of Friday’s fore­cast is con­di­tional IMO. Mean­ing, it depends in big mea­sure on how things play out today.

This para­me­ter (CAPE) looks much nicer, in terms of storm (tor­nado) pro­duc­tion poten­tial. CAPE val­ues of 3000–3500 are worth pay­ing atten­tion to.

I also like the kink in the back side of the CAPE, there around Med­i­cine Lodge. The posi­tion­ing of that in rela­tion to the stronger area of CAPE just out­side Wichita is a pat­tern that tells me an increased severe storm risk is likely.

A closer look…this time at a fore­cast hodo­graph for the same time period (7pm CDT Fri­day) just south­west of Wichita. The hook in the line is what’s impor­tant here….it means wind direc­tions turn sharply in the lower atmos­phere as you get higher off the ground. They also increase in speed.

EHI Val­ues are above 5 in the same area, another indi­ca­tion that both energy and spin will be present in the atmosphere.

The peak val­ues actu­ally start in the OKC area about 4pm and move north. So there is def­i­nitely rea­son to be weather-aware if you’re in the I-35 cor­ri­dor tomor­row. I wouldn’t be sur­prised to see a mod­er­ate risk posted by SPC tomor­row. I don’t think, with the unknown quan­tity of today’s effect on things, that an upgrade to mod­er­ate for tomor­row is in the cards on the Day2 out­look issued later today.

We’ll see in the morn­ing how things from tonight have affected the evo­lu­tion of tomorrow’s weather.

I’m of a strongly mixed opin­ion about today’s chase pos­si­bil­i­ties. If I were like some of my friends who are already sit­ting in West­ern KS, it would be a no-brainer. But with a 3 hour drive each way and mod­els not quite as impres­sive as they were 24 hours ago, I’m get­ting gun-shy. The fur­ther west it is the less likely I am to want to pull the trig­ger. Things look so much bet­ter closer to home tomor­row and (espe­cially) Saturday.

As an exam­ple, in this graphic, the Kansas areas are all green and tan shad­ing. I’d be much more excited about yel­lows, oranges and higher value.

To get those val­ues, I’d need to be in the Texas pan­han­dle – Cana­dian, Pampa, that vicin­ity. Just too far to drive today.

Same para­me­ter, dif­fer­ent model:

A bet­ter feel for the west­ern Kansas tar­get, but the best val­ues are in the Sham­rock, TX area.

Both these graph­ics are fore­casts of tor­nado risk as of 7pm CDT this evening.

My ini­tial thoughts early this morn­ing were to go to Greens­burg or Dodge City and re-evaluate from there. But with bud­get con­straints dic­tat­ing I only spend one tank of fuel, the shift west in the risk area has me re-evaluating.

It’ll be inter­est­ing to see what the deci­sion is when Matt and I get together and look at things in a cou­ple of hours. I’ll post an update when we decide.

A large swath of the plains, includ­ing the Wichita area, is under the gun on Sat­ur­day. It’ll likely be the third con­sec­u­tive day of severe weather in the state, includ­ing a risk for tor­na­does. But Sat­ur­day is shap­ing up to poten­tially be the worst in terms of impact. SPC this morn­ing issued a Mod­er­ate Risk area for Sat­ur­day near the I-35 cor­ri­dor and it is head­lin­ing their web­site this morning.

I’ll post a more detailed look at things later this morn­ing – plan­ning to chase west­ern Kansas tonight – but wanted to let you who fol­low the blog know, in case you hadn’t heard the nearly week-long ramp-up to Saturday’s event, that the like­li­hood of dam­ag­ing tor­na­does and hail is now fore­cast at 45% in the pur­ple area.

From the text dis­cus­sion: “ …POTENTIAL FOR LONG-TRACKED…STRONG TORNADOES OCCURRING FROM THE AFTERNOON THROUGH THE EVENING /INCLUDING AFTER DARK/.”

This is impor­tant. Be prepared.

After look­ing at the most recent runs of the mod­els that update hourly, I’m think­ing Matt & I will be stomp­ing much of the same ground tonight that Kevin, Roxan and I did last night.

This model image (HRRR 14z) is show­ing a peak in the hail para­me­ters in north­ern Morris/Southern Geary coun­ties about 7pm. I like, too, that there looks to be some other peaks along the line (in the hopes it will draw some chasers out of the area I’m tar­get­ing <g>).

That fore­cast graphic is con­sis­tent with oth­ers based on the RUC model. It dif­fers a bit from the WRF model, but not so much I have any dif­fi­culty in mak­ing this my target.

Will Wichita get hail tonight? I think so. I am less sure it will meet severe cri­te­ria. I don’t feel it will hap­pen before dark…earlier I’d felt it might hap­pen dur­ing after­noon rush, but I hadn’t looked at things in any detail.

Here’s the fore­cast area I set yes­ter­day morning:

Loca­tions we saw severe weather:

Tor­na­does were reported out­side my tar­get cir­cle, in Osage and Green­wood coun­ties. The largest hail of the day, so far as I know, was in Green­wood county near Madi­son. I con­sider my tar­get area ver­i­fied, as I did see severe weather within the cir­cle, even if it was not the most severe weather of the day.

At this point, I’m look­ing to a close-in chase if we do one today. I’m just not pre­pared to make a run to Kansas City, Nebraska or Iowa on a low chance of tor­na­does. Espe­cially when dam­ag­ing hail is a good pos­si­bil­ity in my back yard. The down­side to what I’m see­ing is tim­ing. The indices for severe weather start to ramp up in the 4pm time frame…right now that’s the outer edge of the mod­els I use on the day of the storm. SO… it’s back to bed for some rest, and a more care­ful eval­u­a­tion mid-morning to early after­noon. With it being a close chase, I don’t have to make a firm deci­sion until mid-afternoon. That said, I’m lik­ing the area between US 50 and US 400 within an hour of Wichita, as a tar­get area.