Good stuff Steven! Some great info there.
At the time of the change I think the upper air was around what the modeled skew-t suggests but yes, later on into the night it got much colder. The next day we still had isolated airmass thunderstorms when the really cold air was over us then leaving in the afternoon.
We can assume LI's of -2 to -3 from my corrected skew-t above, not bad. Of course thats at the 500mb level where LI's are measured, if we wanted to show the LI max at a particular level of our choosing (700mb looks good in this case) we would have -5 to -7 LI's! But that's not how LI's are done so we can't really use that. In a sense this show's how 500mb LI's aren't always reliable but definately something to check.
CAPE would've been around the 1000 mark, maybe 1500 (I'm just guestimating here through looking at previous skew-t's from the past). Hence a really good storm and some good sized hail!!
Even though the skew t shows storm height of around 7km (420mb where the grey line (TAPP line) and the red temp line intersect), which we know is ok for Ts. I'd say they would've pushed up to around 8km in height, maybe 8.5km if updrafts were strong enough.
Here's some more info from Anthony Cornelius's downunderchase.com website which is really usefull:
When an updraft, or a parcel of air that is ascending reaches a stable layer (eg, a cap), it begins to slow down, but it doesn’t stop immediately. A useful analogy that can be used, is the example of a ball rolling down a hill. The steep the decline (the warmer the parcel of air is to its surroundings), the faster the ball will roll down the hill (the faster the parcel of air will ascend). The opposite can occur when a ball rolling down a slope, reaches an incline. What happens when a ball rolling down a slope suddenly reaches an incline? Will it stop immediately? It certainly will not! It’ll roll up the incline and slow down. The steeper the incline, the faster the ball will slow down (the faster a parcel of air will reduce its speed), and if a ball is placed at the bottom of an incline, it simply won’t move at all (a parcel of air will not ascend, therefore is stable).
The small cap that can be seen on the sounding will easily be ‘broken’ from the momentum of air gained from below it, where it’s slightly unstable. Basically, this stable layer is so negligible, that in our rolling ball example, this will be seen as a very small incline on a declining slope. The ball would have been given an opportunity to already gain speed, and will slow down at the incline, but still proceed over the incline, and will travel down the rest of the slope without hinderence. Similarly, our parcel of air that is rising in the atmosphere that this skew-T represents will see this cap as a small hindrance, and will slow down at this point, and continue rising. For this reason, small caps in the lower atmosphere are easily broken – often without any other assistance.
In my post above I was reffering to the TAPP (grey one that curves up) line as the SALR line, sorry! TAPP stands for the "Theoretical Air Parcel Plot" line. The SALR lines are the same looking type of ones that are evenly spaced to the right, un-abbreviated it stands for the "Saturated Adiabatic Lapse Rate" lines.
Bachh!
Cheers.
