UNR - Warning isssued for storm moving into SW SD. ProbSevere.

2310Z: After a lengthy internal struggle I decided to issue a SVR on a strong storm moving from NW NE into SW SD (2206Z issuance time). Primary reason for issuing was ProbHail which had values of 92% & as MESH of 1.62" right before the storm crossed into the CWA and a warning decision had to be made. This storm had rapidly intensified in the prior 20 minutes with a drastic increase in ProbSevere & MESH values & was moving into the area of our CWA I was most concerned about for severe weather this evening.

However I had reservations based on the near-storm environment the storm was moving into from SPC Mesoanalysis, which showed mixed-layer capping still in place. Furthermore the all-sky CAPE showed very low values less than 500 J/kg across SW SD & NW NE. Initially I dismissed this product as having values unrealistically low but I did notice an increasing rend in CAPE advecting into our CWA. Based off of a conventional near-storm environment analysis I was not a fan of the environment the storm was moving into but it's really hard to ignore a storm with ProbHail > 90% & MESH > 1.5 moving into your CWA, while under a severe thunderstorm watch, with satellite data showing an increasing trend in instability. Looking back at the storm after the fact, the MRMS reflectivity at -20C & 50 dBZ height were right on the line for issuing but at a threshold where I would have been willing to wait a bit & see what happened as the storms moved deeper into the questionable environment in our CWA. Without the tools we're testing this week I likely would have issued a SPS given the lack of reports from this storm & waited a few scans to see how it reacted to the environment across our CWA. In this case the storm began to weaken almost immediately after I issued the warning.

GLM data also was not that impressive on the storm even showing the weakening trend while reaching peak ProbSevere & MESH values I've witnessed with other storms in the west this week. I think this even reverse trend in GLM lightning activity added to my decision to issue a warning based on seeing it with other severe storms in ABQ/MAF so maybe I was anticipating a trend that doesn't actually exist.

Warning decision making relies on confidence in your understanding of the near-storm environment, & that the tools you are using are accurately depicting what is going on in the storm/environment. With this week being the first time we have seen GLM & all-sky products, & with limited use of ProbHail/Wind/Tor, I found it hard to decide which ones to trust when faced with conflicting warn/don't warn information between them and alongside more familiar conventional  products. Obviously this will change as we get more familiarization & training with the products which is one of the primary benefits of these HWTs!

GLM/ProbSevere loop of event:

All-sky CAPE/MRMS RALA loop of event:

Peter Sunday