KSStorm Blog

Good news: no one was seriously hurt. Bad news: a “new” (to me) chase ride is probably in the not-so-distant future. Story later…my sore self is headed to bed.

I was headed out of town and some storms southwest of Wichita went severe, so I decided on a brief chase. Grabbed this video of a cloud that briefly looked like it might produce. It didn’t.

When you’re looking at SPC outlooks, the new day starts at 7am. So our chance for overnight storms is represented by a Slight Risk outlook in Day 1 (today). The rest of us see overnight storms as being tomorrow

I haven’t looked at it in detail, but my feel is that overnight will bring us some borderline-severe hail in the Wichita area, off storms moving in from Oklahoma along with the front.

Tomorrow looks to me like a warm-front play. Those situations have been good to Matt and me in the past year – most of the activity we recorded last year was related to north-moving fronts. Some of the parameters look pretty impressive around Wichita in the mid to late afternoon – nothing like yesterday, but still nice, from a chasing point of view.

I am not planning to go into any more detail on the setup at this point – 20 minutes of glancing at a couple of models is just not enough for me to hang my hat on. I won’t be surprised to see us hanging around Wichita, give or take 50 miles, tomorrow.

Hopefully the models, especially the RUC, will have the same kind of handle on tomorrow they had on yesterday, as I don’t think Matt or I will have the time to do the detailed forecasting we did for yesterday’s event. Between the two of us, I know of at least 7 hours’ forecasting work over the weekend and yesterday that went into our decision-making process.

Speaking of which, a big thanks to ICT Lead Forecaster Brad Ketcham, who talked with us multiple times while home caring for a sick young’n. His forecast hints helped us verify out thinking and he was a big help during the heat of things yesterday afternoon, when we were trying to get in behind the tornado, fighting equipment problems, and outrunning a hail core. As with all these things, it takes a team effort to get it done safely.

Look for a brief post in the morning – with the apparently earlier start, I doubt I’ll have a lot of time for detail, but I’ll update on the target thinking, at least!

A quick update on today before I head to bed:

That was a close call. I’m not sure yet what severe parameter didn’t quite make it, but based on the radar-indicated path of the rotation in the storm that tracked across Wichita, the fact that the tornado reported north of Viola lifted before reaching town is something we should all be thankful for. The track is very near what I would have considered a worst-case scenario for Wichita.

We were a bit behind it (north edge of Suppesville) when that tornado was reported; to us it looked like a rain-wrapped funnel. But I don’t doubt at all the two reports from 7-8 miles N of Viola. I won’t be surprised to find that the actual distance was closer to 5 miles; it is quite hard to correctly estimate distance in those situations. I would have pegged it about 2 miles NE of us, but I think I was probably estimating too close.

In and amongst everything else tomorrow, I am going to have to find time to re-configure the power distribution in the van. We lost the PC that handles GPS and streaming right in the heat of things, and after it came up were having problems with the wireless access point I use to get into it from the laptop. Aging wiring in the van, a bit too much power pull on the inverters, and a pair of aging inverters are the likely culprit. I’m hoping that replacing the inverters and running a dedicated power wire for the cell booster will fix the problem.

Game on again for Wednesday – I’m sitting out tomorrow, due to too many family commitments and the conditional nature of the risk.

Here’s the updated SPC Graphic:

It’s not a lot of move from earlier this morning, but now the area lays about where I really expected it to be….maybe still a bit further south than I expected. 7am (12z) model runs aren’t quite done yet, so I’ll be interested to see if the low is out of position compared to where the models had predicted it. It was slightly off of the predictions earlier this morning, a position that would tend to favor the southward adjustment.

I’m going to shift my targeting thinking just a bit south – 20-30 miles or so — now that the event is within the realm of the RUC. This model is more consistent with the NAM solution, which was most consistent with other models over the weekend. The faster GFS solution seems to be the outlier now. I still think the high risk area may be adjusted west a little in the outlook update due at 8am CT.

We’re just waiting to see where the cloud deck erodes now. Still a few hours from a firm targeting decision, but I know this much: I’m not going to play with the hordes in northeast Oklahoma. I’ll take our road network over theirs any day of the week. My instinct to stay close because of risk to the Metro is staying firmly in place. Best guess right now: I’ll be putting up with cell phone frustration along US 160 a good portion of the day. I’ll take that to US 166, though.

This will probably be the last discussion in any detail – lot to get taken care of before my data session with Matt at 11, and looks like we may be on the road a bit earlier. Look for updates on Twitter: @scott_roberts and follow the video on the Live Tracker (button at the bottom).

I will post an updated graphic from GRLevel3 sometime after the SPC outlook is issued, so you can see exactly where it sits. Sometimes the small map on their site is hard to peg exactly where the line is in relation to where you are.

This image, from NWS Norman, is the most concise explanation of today’s setup I’ve seen yet.

The Slight, Moderate and High-Risk areas today are indicating only the number of storms expected. Anything that goes is expected to be severe…much of it high-end. Usually, the risk areas indicate forecasters’ best feel of both the change there will be storms and how intense they’ll be. Today it’s nothing more the % risk for any 25-mile circle to get whacked.

I’m going to share a different graphic with you today. This is one of the overlays available on my radar application, GRLevel3. It is a bit confusing because it crams what is four images on the SPC website into one.

The red circle, marked HIGH, in the southeast corner of the image is the SPC high risk area. Very close to it, in orange, is the 30% tornado risk. Now look just southwest of Wichita. The light orange line closest to Wichita is the 15% risk of tornado line. The yellow line, next west, is the SPC Moderate Risk line.

Now the item of concern, IMO. The Purple line, marked SIG. That denotes the area in which SPC believes there is a “10% or greater probability of EF2 – EF5 tornadoes within 25 miles of a point.”

Also of concern, from a property damage potential standpoint: the light green line next to the west – 45% probability of hail. And though I don’t show it on this view, the area is hatched on the SPC site, meaning a “10% or greater probability of hail 2″ or larger within 25 miles of a point.”

So, in spite of the high risk being moved to our southeast, I think it’s premature to let out our collective breath. The hazards if something goes today are in the significant category.

I expect to see the High risk area come back just a bit to the west. But from the standpoint of chasing in the metro area and the population impact of the worst weather, I’m liking where it is a little better than where I thought it would be. The high-risk bullseye will distract many of the uninformed people who will clog the roads and make it hard for those of us whose job is to inform others of the events in real-time to do what we do. The casual chasers will focus on the high risk and leave us alone. That leaves the untrained “chasers” – called a number of other derogatory names by many – the people for whom “Twister” was a training film. ‘Nuff said. I still expect the roads to be a zoo, but with the high-risk bullseye to our southeast, we’ll lose some of the gridlock.

I’m not making any fine-tuning decisions on my targeting until the 0z (7am) models are out, but I will say my thinking hasn’t changed a lot concerning where and how we’ll approach it. We may not get on the storm of the day…but if it looks to me like storms will directly threaten Wichita, I’ll defer to staying in the metro. It’s a day when I take my warning responsibility – and if something happens, my responsibility to help – more seriously than getting the greatest video. There are a lot of days those two motivations are competing in me, but today it’s a no-brainer for me.

Time to work so I can have the deck clear by 11 for an in-depth discussion with Matt. I may post a short update about 7:30 or 8, otherwise the next one will likely come as we get ready to roll – right now we’re planning on being in the field by 2:30-3pm.

An out-of-band commend from a friend concerning this morning’s post made me feel the need to clarify something I said in each of the last two posts. That’s the comments about patterns that look like certain historical tornado days.

See, I’m a pattern person. I don’t have but a smattering of meteorological background, and any knowledge I have is the result of watching others and the patterns of the atmosphere. That and a little reading inthe past few years.

So when I say the pattern for resembles May 3, 1999, I’m not really saying I think the outcome will be the same. I’m saying the forecasts, at least according to the models I believe and the patterns my mind recognizes subconsciously, indicate the highest probability for severe weather in a pattern that is like May 3rd. In other words, I buy into a solution that has big storms in both Oklahoma and Kansas, about 90 minutes to 2 hours’ drive apart, including strong, long-lived tornadoes.

Do I think either Moore or Haysville are gonna get clobbered again? As of this moment, no. Others have said this bears resemblance to the US 160 outbreaks in 2004. I mentioned a passing resemblance to the Andover tornado yesterday.

I think what this really means is that all the ingredients are there. The way they are setting up resembles, in some fashion, aspects of one or more of those days. But this *is* forecasting, and we *are* talking about the atmosphere. The devil is in the subtle details we *can’t* forecast until 6-8 hours before storms fire, if then. Any one of a laundry list of things changes in the wrong way and we get nothing. A couple of them change the other way and we have a major problem.

The takeaway is that tomorrow is not a day to be complacent about. If you are in the I-35/135 corridor give or take 90 minutes’ drive, south of I-70, you should be aware of your surroundings and how they are changing between about 3pm and 10pm tomorrow.

BTW: The models came into a little better agreement at 12z (7am). In Kansas they are narrowing down the area of potential, IMO. They are also elevating the Oklahoma potential. I don’t see a reason to shift targeting much yet. My line to be somewhere along at initiation is somewhere in the Clearwater to Kingman vicinity…depending a lot on what happens tonight and through 1pm tomorrow.

Pretty much in line with what I expected, the wording of various weather service forecast products has taken another step up in tone, and I’m going to echo the step-up. Tomorrow is a potentially dangerous setup for a lot of people. Today is the day to make plans about shelter — to consider the places you plan to go tomorrow and find out, if you don’t know, where shelter locations are in those places. A hand-held or desktop weather radio is a good investment — and of course in Kansas and Wichita, you can rely on KWCH and KFDI to have it very well covered (gratuitous plug now finished).

There are still some difference in model timing and the resulting feature placement. They’re gradually coming closer, though. The way I see it now, the differences are between the worst weather being from just west to just east of Wichita and it being in eastern Butler/Greenwood counties. There are also some differences with the southern extent of the storms. I’m not sure whether I’m being chaser-selfish or more concerned about protecting life and property where I live — but I hope the scenario plays out closer to the NAM solution in Oklahoma and closer to the GFS solution in Kansas. That has the dual benefits of keeping the Oklahoma chasers off southern Kansas roads and in their own back yard and shifting the worst weather to less-populated areas all around.

Should the opposite happen, we may be looking at a May 3, 1999 scenario displaced a bit to the north and east.

Overview: Storm Prediction Center Graphics

Categorical Risk

Total Probability of any Severe Weather

First change to note since yesterday: the Moderate risk area is slightly east of where the risk area was painted yesterday. Wichita is now on the west edge instead of near the middle. Most NWS forecasters have been buying the GFS model throughout the ramp-up to this event. It has been the most consistent throughout. The NAM (or now that we’re in the 2-day range, the NAM/WRF) model is a bit slower evolving the features and leaves the risk area back to the west, basically what’s outlined by the Slight risk above.

I would not focus so much on the 45% probability of severe weather for the Moderate Risk area as I would on the hatched part of the graphic on the right. That indicates the expectation among forecasters that pretty much whatever goes up tomorrow will be capable of high-end severe weather (EF2-EF5 tornadoes, 2” + hail within 25 miles of any point in that hatched area).

Why is this? Here are graphics showing the factors I find important. The values I list underneath them are my estimates for Wichita.

Surface Temperature: 78-82 Surface Wind: SE gusting to 30

700mb Temperature (an indication of cap strength): +5 C. 700mb Wind: SW @ 50 kts

GFS CAPE:  1000

GFS CIN: 0 to-5

NAM CAPE: about 2000

NAM CIN: 0

GFS LI – best just east of Wichita

NAM LI – best just west of Wichita, but a respectable –7 overhead

LONG-TRACK STRONG TORNADOES WILL BE POSSIBLE...
PARTICULARLY FROM OK PORTION OF I-40/44 NWD
INTO SCNTRL/SERN KS DURING THE EARLY EVENING.

POTENTIALLY LONG-TRACK TORNADOES DURING THE AFTERNOON AND EARLY
EVENING ON MONDAY. SUPERCELL THUNDERSTORMS ARE EXPECTED TO DEVELOP
DURING THE MID TO LATE AFTERNOON JUST AHEAD OF THE DRYLINE AND RIGHT
MOVING STORMS WILL QUICKLY MOVE OFF TO THE NORTHEAST AT 40 TO 50KNOTS.

NWS Norman (emphasis mine):

SEVERE THUNDERSTORMS ON MONDAY AFTERNOON AND EVENING...MAY MOVE AT
SPEEDS GREATER THAN 45 MPH...LEAVING LITTLE TIME FOR PEOPLE TO REACT
TO WARNINGS. YOU ARE ENCOURAGED TO THINK AHEAD TO WHERE YOU
WILL BE ON MONDAY...HOW YOU WILL RECEIVE WEATHER WARNINGS...
AND WHERE YOU WILL SHELTER IF A STORM APPROACHES YOUR LOCATION.

My target for tomorrow stands at this point. Essentially a back porch chase.