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: 78-82Surface 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.
…but the question is: where? With the hordes of chasers to be in our area Monday, space on the roads may be at a premium, and a bad forecast decision may not be recoverable due to the traffic.
That said, as the models sit at this moment (and the latest models are rolling out as I write this, so I have not seen them) I am going to be somewhere in a box bounded by K-14, US 77, US 56 and US 166. My best read at this point puts the Wichita area under the gun, perhaps in a significant way. It may come down to what boundaries are laid down by tomorrow night’s storms and just how much clearing we have ahead of the dryline. One thing to be careful of: some of our biggest storm days have been cloudy longer than was thought would give the atmosphere time to recover. Andover was one of those days. I have some concerns of a repeat.
We’ll see how that call drifts over the next 40 hours or so…
Won’t go into a lot of detail, as I’m writing this on the phone and can’t put in the graphics I’d like to. But for those who like a heads-up, this is it. Thursday looks to be active across a swath of the plains, including the Wichita area. Current outlooks place the risk along US 81, give or take 150 miles, from at least the KS/NE line to south of Dallas.
Good news: the chasers will have enough space to spread out, rather than needing to rent a double-decker bus like last Thu in the TX panhandle. (Just kidding)
Bad news: the center of the outlook skewers some fairly significant population centers. Move last week’s Lakin tornado 180-200 miles east and imagine the difference. Not saying it will happen that way, but I always prefer open areas to populated ones when looking at storm risk. I love to watch the strength of nature, but not when it hurts people.
‘Nuff about that. I’m planning to chase Thursday, and if you live in Central KS or OK, I hope you’ll have a weather radio near you all afternoon.
Thought I’d take a stab here and see if there are any software coders following the blog feeds. Specifically, I need someone who may be interested in helping found a company. I have several ideas for software that will help connect radio & TV stations to the Real-Time web – in most cases their present content management tools just don’t cut it. Real Time News Link is a plug-in that would enable their content management systems to exchange information directly with web backends and the Real-Time web (Twitter, Facebook and so forth).
I’m heading to Dallas next weekend for StartupWeekend – over three days, several people band together around various ideas and build companies. I’d be willing to spring for the gas and your event ticket if you’d be willing to come help me recruit a team of coders to put out a prototype of the application by Sunday night. To keep the topic form getting too off-target, I’ll refer you to the RTNewsLink website to find out more about the project. Or email me to find out more.
Other than while we were parked at 53rd and Oliver, I don’t think we left the city limits of Wichita yesterday. If so, it wasn’t for long. But we made the entire circle of 4-lane roads, and drove I-135 twice. Matt is out on Tuesdays for class, so my driver was my awesome wife, Roxan.
After finishing work and model analysis, I decided we’d probably be looking just SE of Wichita for storms to fire, somewhere in the 4pm timeframe. So we headed to lunch – as it turned out, right on the dry line – at Olive Garden on Maize Road. The precursors to what would be the first storm of the day were already thickening overhead. After we finished lunch, I set up the little bit in the van that has to be done each day, and just as I was getting streaming going, the first warning was issued.
We had to pick up Cristi at about 3:45, so following the storms into Butler county wasn’t in the offing. However, we did sit for a time at 53rd and Oliver and stream video of the storms to our northeast. After picking up Cristi on the south side, we sat in a parking lot and waited while watching the tops of the clouds roll. The towers were still getting laid over by winds aloft, though. We eventually went to I-235 and 25th Street, and sat up on the Big Ditch end of the bridge there for half an hour or so.
Failing to note the time, we decided to take a short break at the Ridge Road/21st QT. Unbeknownst to me, KWCH had wanted to use the video from I-235 and 25th at the top of the 5pm show. We were able to get lined up on an SLC formation over north Wichita, but I don’t think that video ended up being usable. We did the QT run with the camera focused on that feature, which seemed to be trying to get organized. As we got back in the van, there was no rain, but we suddenly went to pea-size hail, which lasted for about 5 minutes.
We decided to go around 235 to south Wichita, finding in the process that the dry line was still right up against 235. The closet-to-severe conditions we experienced were while we were driving around 235. The whole trip, wind was 40mph+ from our right – so from the NW, W or S depending on where we were. The south winds (inflow) were the worst, kicking up dust at I-235 and West and making the van nearly impossible to control. I’d estimate about 50mph out of the due S at that point. Did not see any branches falling from trees yet, though.
The rest of the evening was watching things gear down, really. We shot video and I did a phone interview at 6pm, looking north from Harry and I-135. I toyed with breaking off for the storms developing to the south…and if I had, we’d have been on them when the outflow from the northern storms hit, causing the warning for eastern Butler county/Greenwood county. But such decisions are all part of the game.
105 miles, five hours, never left Wichita. Gee, it’s like I was back at KFDI 
The Thunderstorm Watch is from here northeast, until 10pm. I think SPC went with that because the tornado risk is so conditional and so early in the watch period. AFAIK, a tornado would verify a thunderstorm watch, anyway.
One of the models had a nearly perfect handle on this first batch of storms in its run around midday. THey are p laying out almost exactly as the model showed, scooting to the northeast and out of our area with apparently low-end severe weather. Based on that model (with some reinforcement from another one updated more frequently) I’m looking for the weather maker storms to fire a little southeast of Wichita….it’s going to be a close call as to whether it misses town, I think… In that batch of storms, any severe mode is possible. I think any tornadoes that happen will be fairly brief, as the storms should line out pretty quickly.
The dry line and cold front (they are pretty close together, if the front hasn’t already passed the dry line) are continuing to move through the metro now, but they’ve slowed a bit, I think. The last batch of storms fired right on them. I think the next batch will be out ahead just a bit.
Matt and I headed out about 2:30, with an initial target of Hutchinson. We arrived about 3:15 and commenced what turned into a long wait on nothing, sitting in the McDonald’s/Kwik Shop parking lot at US 50 and K-96. Strongly reminiscent of the last bust (a year and a half ago), we streamed video of the McDonald’s employee parking lot for about 2.5 hours…watching a good waste of so many things develop.
We knew going in things would be a challenge, but I think it was on both our minds that the biggest challenge was just where rising air would pierce the cap. The air really never got to rising, so that never became an issue.
We did decide at one point to make the drive to Pratt, but I think we were both realized by then our hopes were dwindling. it was really, I think, a “follow the other chasers” moment more than anything that caused us to really think anything was going to go up. Upon arrival in Pratt, we parked in the McDonald’s parking lot. Do you sense a theme for the season developing here?
Twenty minutes later, we called it a bust and settled in for the 80-minute drive home. Gotta have these days every once in a while right?
I plan to be hanging out a few miles east of the dry line later this afternoon. My best feel is that the red area is slightly too far west, but it’s also based on models as of early this morning and later models are a little further east. It wouldn’t surprise me at all to be in or driving through Iola at some point this evening, for the second time in four days.
It looks like the tornado risk will be very shortly after initiation, with a quick evolution to a line or line segments. If we get line segments, I might try for a tail-end Charlie play, but I think the damage from this system will come, as it did on Friday, from the winds in the line.
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