Moderately Unstable

Thanks, edited.

Short version, giant hodograph, high critical angle. Longer version...When you're looking for a strong tornado, you look for that big right turning hodograph. There's also a decent amount of academic literature now that discusses the link between critical angle and strong tornadoes. That's the angle between storm motion, and the low level shear. The closer to 90, the more likely you are to have an environment favorable for producing a strong tornado. Think about a boat, flowing down a river. That's the storm. Ok, now, imagine you tie a giant rope to that boat, and yank the back of it at a 90 degree angle. What happens? It spins. Or you fall into the river cause you thought you were stronger than a multi-ton boat in a current. Anywho, combined with a low LCL, large cape, AM cap, discrete cells...you have a problem on your hands. Hodographs let us plot wind speed and direction with height. It's an easy to read way to measure speed and directional shear together. When you combine those, we find that a large, right curving hodograph, signals that the *wind field* in an area is supportive of tornadoes. I feel compelled to add at this point...when we see a large, right curve, we're expecting a right-moving supercell. A "right mover", moves to the right of the mean flow. Hodographs are an easy way to determine this (and remember it). Large hodograph, in right quadrant, with right curve, equals right mover. Right movers tend to produce stronger and more frequent tornadoes due to some fancy dynamics. For tornadogenesis, we focus on the curvature of the hodograph in the first 2-3 km of the atmosphere. This is telling us about low-level shear. This is another area of tornadogenesis research that has become more clear in the last few years. It is part of why some supercells produce tornadoes, and others don't, and it is how the SPC can say now, x region will likely see supercells capable of "all hazards", where others will see a large hail threat. Basically, you start with a mid-level mesocyclone, and then that storm pulls in some additional rotational energy which enhances low level rotation. You can detect that on a hodograph through its low level curvature. You may also have noticed folks talking about the low "ground scraping" LCL's. That is, in essence, the cloud base. The closer that is to the ground, the easier it is for that strong low-level rotation to actually get to the ground. Skew-T's, and hodographs, tell us all of this information. At the end of the day, hodographs are one plotting method used to tell us what's *possible*. The reason we use hodographs to prog wind profiles in severe setups, is they allow us to *easily* and *quickly* identify how risky a particular setup is, for a certain area. Thus when you read something "looks bad", it's because that chart or graph, is designed to allow us to easily interpret what we're viewing and come up with solutions. We could just look at the wind barbs on a Skew-t, or winds on pressure surfaces, but hodographs give us a better snapshot of what's happening at different heights, when it comes to shear and spin. A tip for the future: don't overcomplicate chart analysis. When you forecast, you're considering many parameters. What's the starting setup? Do the models correctly capture this? Which capture it best? OK, what are the models that understand the situation to start with saying WILL happen in the future? How are they changing their forecasts with time? What do I know about the local area that could affect this setup? Do the models STRUGGLE with this setup, or area? What does this setup remind me of (or if you're me and have a bad memory, what does this remind a computer database of)? In all of that, you're going to look at many different charts, tables, plots, and figures. Trying to get down deep into the weeds of a single hodograph in a scenario like this, isn't something anyone has time to do (or I suppose...should have time to do). Same is true for a Skew-T. I see folks overcomplicate them all the time, and you can come up with plenty of interesting things from them, some of which are useful. At the end of the day though--for a skew-t, what I'm going to look at....: what's the temp profile, what's moisture look like, is there a lot of CAPE, ok, where's that concentrated (aka, what's the profile), is it surface based, what's the wind, any significant advection occurring, anything else jumping out at me? If it's particularly noteworthy, what are possible analogs of that setup? Ok, got it, NEXT. Thus, for a hodograph--long curvy rightward turning hodograph = bad. The bigger, and stronger the curve, in general = more bad. .

Well, the short answer is, it doesn't always. For small hail, you can get rain-hail-rain. As you know, hail is produced when we have an updraft strong enough to lift rain droplets above the freezing level, which then condense into a hail embryo, which grows with time. If you picture a storm traveling along, the updraft is ahead of the storm, pulling in warm air. That's also the part of the storm that keeps hailstones aloft. Thus the densest objects, aka heaviest relative to surface area, will fall faster, after growing to sufficient size high up in the upper levels of the storm clouds. Smaller hail will fall next, relative to the direction of motion, as it gets more tied up in the overall wind structure of the storm. Rain follows last. Large hailstones are falling from beneath the tallest parts of the storm cloud--areas that have the highest updraft speed, right after the rain free base area. As they fall back into the lower levels of the storm, they're too heavy to be "mixed up" by the turbulence in the mid-level flow. The main cold downdraft region is behind this segment of the storm. Hence why you will often see large hail-small hail-rain. Now, this rule applies for supercells and other storms with very strong updrafts. But not for marginal hail cases. In other words, if you have, say, a storm producing pea sized hail, the dynamics will often have that small hail corridor within a surrounding area of heavy rain. You can see this easily using dual pol radar products. In this case, the storm is producing through one of a few mechanisms, a region of marginal hail, and that correlates with the greatest intensity of precipitation. E.g, maximum downdraft intensity = hail zone, for small hail. Having a relatively cold air mass with low freezing height coupled with a nice strong cold front is a great way to produce this type of hailstorm.