Maybe a wind farm? – Wildcat 

NW Mercer county had some higher values of AZshear appear, but not flagged as an area with TOR potential I’m guessing because it’s in a an area where there is no reflectivity. 

Beam blockage in velocity data makes it easy to discount AZshear. Screen capture of similar time and blockage – Wildcat

Not obvious on radar, and likely an EF0, but small probs on AZ shear at time of report. I would not have warned on this and probably would not have warned, but probably would have after the fact given the persistent of similar signal in AZ shear data – Wildcat

Along with radar data, near-storm environmental conditions are an integral part of the  warning decision, so including it in the TORP display would be very useful to warning forecasters.  Contoured plan view data of  MUCAPE, MLCIN, 0-1 km helicity, etc should be added to the “Weather Related Overlays” to tell if storms are moving into more/less favorable environments. Some other environmental data items that could be added to the list of graphed data trends: DCAPE, 0-6 km shear, 0-3 km helicity, Other forecasters will have their own preferences for what environmental parameters to include.

Posted by Rigel

Here’s an example where Az Shear was overly excited by bad Velocity data yet TORP was not tricked. Despite Max Az Shear being the highest ranked predictor for TORP, TORP did not produce an object for said area (at least above the 20% threshold I’m currently viewing). When looking at reflectivity data, clearly there is no developing mesocyclone (or really anything at all) in the Az Shear couplet’s vicinity (not to mention the velocity data is just obnoxiously extraneous).

P.S. I missed a Tor while making this. Whoops!

-Wx Warlock

A quick spin up occurred just east of the KDMX radar that was difficult to identify on velocity data alone with any amount of lead time. There was some enhancement in surface convergence at the 1604z scan, but potentially not enough to grab your attention or warrant a tornado warning. By the next scan at 1606z, there was a couplet with 30kt+ of Vrot. At the 1607z scan, there was a CC drop collocated with the couplet. It might have been difficult to get much lead time on this tornado with radar data alone. That said, the two screenshots from TORP/AzShear might have led you to issuing, or at least drawing up the warning, at the 1604z scan with the sharp jump in probability and AzShear maximum as noted on the graphs on the left. This is a good example of where the product could have gotten you a minute or two extra of lead time. -newt

The trend on this storm has really come up, and a rapid increase was identified. Couplet visible in SRM data as well and I would issue a tor on this storm, and probably would have a scan before based on AZ shear data – Wildcat

There was a nice example of small vortices forming along an outflow boundary with a line of convection in the FSD county warning area around 1545Z  on 16 April. These small vortices are sometimes  associated with storm damage from  non-supercell tornadoes or “gustnadoes”. The TORP identified one of these circulations with rapid increases in both AzShear and Spectrum Width Maximum trend.

Posted by Rigel

Our morning real time case has taken us to Iowa with an ongoing broken line of thunderstorms. While there have been a few signs of mesocyclonic development, I noticed a known issue with TORP object detection as a QLCS approached KDMX along the radial from the south southwest. While Az Shear was generally unimpressive with this line, the QLCS’s orientation with the radar caused a couple TORP objects to generate. While their probability values were low (near 30%), it still caught my eye as something to check out and then immediately write off after checking radar data. This hiccup wasn’t necessarily disruptive to my forecasting process, but was useful to know about before starting off today so I wouldn’t be confused when I see it.

-Wx Warlock