Collection of Day Two Thoughts

Day 2 has featured more convection, and has been a helpful day testing these products and how they help in warning operations. Although I might not feel confident making warning decisions solely based on any of these tools, I think that each tool provides a valuable piece of information.


To keep things short here with all the observations, PHS was very helpful today in showing how the QLCS situation would evolved with several areas of embedded rotation. Having CAPE with SRH together showed how these came together, and in conjunction with velocity highlighted rotation updrafts within PHS. This proved to be a helpful pre-storm evaluation. A few storms began rotating, and then everything began rotating as the PHS model indicated.


Observations Related To Warning

The developing squall had a linear appearance at first. As time progressed with more embedded areas of rotation, this became a lot less neatly organized.

Here is a look pre-warning for a tornado warned cell with ProbTor increasing up to almost 40 before moving off the point.



A zoom in on an impressive overshooting top. Sorry for the reverse loop.


Here is a V-notch like structure. Though it doesn’t correspond with a radar V-notch, it does indicate how strong an updraft this was.



And here’s the radar look of that, which appears to somewhat match the configuration seen aloft.
Interesting Signals


One thing to note early was that the PHS forecast had a lot of convective debris lingering in Iowa that was not present in reality. This does not appear to have impacted the instability parameters very much.

We’d mentioned looking at the dewpoints for the tendency for aggressive convection. But it only seemed slightly high compared to reality.

We did have a blob near Sioux City on Gremlin that didn’t really correspond with any signal on radar, and it didn’t seem to have satellite signal to go with it. Not sure where it came from, but we were able to see it was erroneous.


Here’s a look at GREMLIN with waves and wobbles following the GLM lightning.



Here’s another fun look at where it seemed the convection on the northern flank may have affected GLM quality with values decreasing on the north side. Note the reversed image loops.
Here’s an instance where GREMLIN’s max intensity happened before a lightning jump. Unfortunately this is reversed, but GREMLIN struggled to resolve an intensifying storm in the middle of the line.
Here is an example of GREMLIN losing a cell in 3 surrounding cells.


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