So what are some of the hazards that can affect roadways, different types of roadways, and how should that affect your behavior as a storm chaser when the roads become more dangerous?

So the main one that you can think of is dirt roads and them turning to mud when there's precipitation on them.

If you've had a prolonged period of heavy rainfall, a very wet few months ahead of time, sometimes the road network, and especially if they're dirt roads, can become a little bit questionable.

Even though you may have a lot of roads at your disposal, they may not be of the best quality.

You might have a chance of getting stuck on those if you do take them.

So that is one.

You always want to be looking at the quality of that, maybe not making rash decisions, taking a random dirt road.

What is your story, if you could share it with us, and what lessons can storm chasers take away from it?

Could you talk a little bit about that for a moment and how it can actually help to measure the amount that dry air might be impacting a supercell from developing?

Yeah, so eCAPE is a relatively new variable that has been developed in the last few years.

And the basic premise is that normal CAPE, convective available potential energy, our typical measure of instability, that doesn't factor in a lot of times the air that the updraft is ingesting.

If you have a lot of dry air in the environment, that can actually... reduce the amount of instability that the updraft is working with.

So if you have an environment of 4,000 joules per kilogram mixed layer CAPE per se, but you have a lot of dry air aloft, a real good amount of dry air aloft, depending on how much dry air is there, it may only be ingesting about 1,000 to 1,500 joules per kilogram of that CAPE.

And of course, you might look at a sounding, see 4,000 joules per kilogram of CAPE and think, well, there's extreme instability in this environment.

But in reality, if the thermodynamic profile is such that there's a lot of dry air aloft, the updrafts that go up in that environment may not even be experiencing close to what these observed soundings are showing.

Where's your mind at in those situations?

What are geopotential height contours and what do they represent?

So in upper air maps, we do not use pressure as a way to analyze the map.

That is what we do at the surface because the surface is not a constant pressure level.

Pressure is changing across that level.

In the upper atmosphere, we have different pressure levels in which the pressure is constant in that level to analyze.

So for example, the 500 millibar map, every place on that map is 500 millibars.

The pressure is constant across that surface.

What does a trough's tilt tell you about its severe weather potential?

What are some other common things that happen where you do need to adjust on the fly? Things that you, of course, were already thinking about beforehand, but can definitely influence where you wanna go and stage and wait for those storms to develop.

So that's going to be situation dependent and it can be different little things in different chases.

An example of this might be, like we said, maybe you were targeting an outflow boundary and instead of retreating northward like it was expected to do, maybe it has stayed a little bit farther south than you thought.

That would be something that might allow you to adjust.

A great example of this from a personal example was May 18th, 2025, the Arnett, Oklahoma day and then the Kansas wedges after dark.

Our initial target was in southern Kansas that day.

I believe it was the Medicine Lodge area.

So how do you figure out if you made an actual mistake or if you had an excellent plan, you executed it well, and it was just outside of your control for that day?

What storm scale process is likely allowed the Plainfield Supercell to produce an EF5 tornado?

so it's a little bit tough to tell 100 because we don't have really high resolution radar data from back then but the national weather service office in chicago actually digitized the radar from back then and you can find that on the event page they have for the plainfield case but what it appears happened with this storm is we got a supercell to develop It produced an outflow boundary, and that outflow boundary kind of surged out ahead of the storm.

So there are some photos from before the Plainfield tornado began, and the storm looked very outflow dominant.

You can see a shelf cloud on it, very strong straight line winds with it, but nothing that would scream like this was going to turn into a tornadic supercell.

What looks... to be the case here is that the storm actually caught up to the boundary, its own outflow boundary, and ingested that boundary.

And as we know, outflow boundaries are often critical for taking environments that maybe are not all that favorable for tornadic supercells to ones that become significant tornadic supercell producers.

And that's what happened here, it looks like.

So now that we know what may have occurred, what are some practical forecasting and chasing lessons we can learn from the Plainfield case?

What did the October 5th supercells around Phoenix teach us about moisture, instability, boundaries, and storm mode in the desert southwest?

In Phoenix on October 5th, we actually had some very large hail-producing supercells with some baseball to even, I believe, some softball-sized hail reports, particularly in the West Valley, which you never see in Arizona at all.

And what kind of caused that was a little bit of a plains-type dry line that developed.

We talked about those 60s dew points that were streaming up into central Arizona.

To the west of that, very dry air.

What does that remind you of? plains dry line you have very hot dry air to the west warm moist air to the east and we actually had a dry line developing in central arizona and the storms developed on that with the dynamics at play they were able to become very robust supercells so just because you're not in the plains or the midwest or something doesn't mean you can't get those classic severe weather type boundaries and whatnot like a dry line.

A dry line can happen anywhere, and we saw that on October 5th.

Why did the tornado threat increase dramatically during the early morning hours of October 6th, even though the storms developed near the minimum of the diurnal heating cycle?

From a radar perspective, how do features like a descending reflectivity core change your confidence that a supercell is about to produce or intensify a tornado? And I'm pretty excited to hear the answer to this one because this is even well outside of my realm of understanding.

Yeah, this is actually something that there's research being done right now on this by people like Chris Broyles.

They're looking into a lot of these strong to violent tornado cases, and they're finding a lot of these descending reflectivity cores are in place and actually occur immediately preceding tornadogenesis, and the Parkersburg case was no different.

You have to kinda look on 3D radar, so it's m- not something you might often see in real time.

You can see it on 2D radar in reflectivity sometimes, but it can be a little bit tricky.

But if you have a 3D radar picture, you can often see a little core or little blob of stronger precipitation and stronger flow descending down into usually the region near the hook echo.

Sometimes this will occur well before tornadogenesis, and it actually may signify the beginnings or intensification of the hook echo.

But can you explain how the gravity waves, especially that trailing one that you mentioned in your Convective Chronicles YouTube video, how did that likely influence mesocyclone strength and tornadogenesis for the Parkersburg storm?

So how should ensemble models, which are, I wouldn't say the opposite, but definitely qualitatively different than the deterministic models, how should they be used when you're three to four days out from a potential event?

Yeah, so as we said, ensemble models basically take the model that you have, so let's say the GFS model, the American medium range model.

You take the GFS model, you run it a bunch of different times with slightly different initial conditions to get a bunch of different model outputs.

An ensemble puts those all together, and then we can average those out so we can get the average 500 millibar pattern going out in time.

We can get the average moisture, average surface dew points going out in time.

Rather than just taking one model at face value, we're combining them into a holistic view, and that allows us to weed out some of the wonkier model runs.

Say if one particular ensemble member is way off from the others, we're averaging all those ensemble members out so we can weed out the wonky runs.

Why is it important to compare multiple models instead of just relying on one?

What reflectivity changes signal that a storm may be transitioning into a supercell?

So the most telltale sign is that you start to see more of a kidney bean shape on radar.

The initial updrafts might be small and they might be just going up, but if you have a strongly sheared environment with strong deep layer wind shear, oftentimes you'll start to see a kidney bean shape.

So a little bit of curvature in that storm, that can tell you that the storm is starting to rotate.

You'll also see very strong reflectivity gradients going from just outside the storm to in the precipitation region of the storm.

So you might see very heavy precipitation in the core of the storm on the very edge of the reflectivity region where the storm is showing echoes.

And then right outside of that in the clear air, you'll see no precipitation echoes.

How can people tell the difference between a velocity signature that's showing a mesocyclone versus a velocity signature that might be indicating a tornado is ongoing?

lines?

So when you're identifying boundaries on a surface map, you want to not just focus on one particular aspect, but you want to see a confluence of factors come together in that location where the boundary might be to increase your confidence in placing that boundary.

So the first thing you want to look for is wind shifts.

is the wind to the south of the boundary the potential boundary more out of the south whereas to the north it might be out of the east across a broad area that is a sign that you might have a boundary in place you can also look for temperature gradients and moisture gradients so do you have say mid 70s temperatures on one side of the boundary and maybe 60s low 60s temperatures on the other side that could be a sign that you have a boundary also moisture can be a boundary an indicator of a boundary so you might have higher dew points on one side than the other and of course this comes into play with a dry line you want to see those real high dew points on the moist side of the dry line and much drier dew points much drier air on the west side of the dry line If you do a surface analysis as well, a full surface analysis where you're marking in your pressure contours, your isobars, you'll often see a pressure tongue associated with the boundary location as well.

So the pressure lines might kink over a certain area, and that could be a signal that you have a boundary in place.

Again, you don't wanna focus on just one of these.

Just because you have a temperature gradient across a certain area does not mean you have a boundary.

Now what do skew-T soundings tell us about instability and capping?