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As has been noted, TORP lead time is nearly non-existent when it comes to QLCS events. This is especially true when applying a threshold filter >40-50%. However, in this case and others assessed so far this week, FAR with TORP is relatively low for even these marginal/transient cases. The example above displays nearly zero lead time to confirmed event (~1244 UTC), though would be eye-catching should a TOR warning not yet be in place. -QLCS
This is a difficult case with the spin ups nearly perpendicular to the radial where most of the damage occurred. TORP wouldn’t have provided much lead time as it very quickly jumped from 21-76% in one volume scan after the couplet had already developed. There was a well-defined velocity signature at the 1217z scan from KLWX. 
AzShear started to light up at 1214z. Given the environment, it would have been difficult to lean on AzShear and make a tornado warning decision before any signature developed on radar, but in hindsight some lead time may have been possible using that 1214z AzShear signature. -newt
Very weak AZshear detection although no TORP on this scan. Have to go back 3-4 scans to see a TORP object – which was only one single frame at 33%. – Wildcat
An area of higher AzShear moved close to the KLWX radar at 1221z and TORP struggled to pick up on this. TORP has a known QC to filter out data within a certain range (30km) from the radar, but even when that was turned off, TORP did not have anything. 
Looking at the velocity data, there is a couplet there just to the northwest of the radar where AzShear is maximized. So, even though AzShear responded well to the couplet, TORP struggled due to the close proximity to the KLWX radar.
The TORP graph shows that when the couplet with the high AzShear moved farther away from the radar, the probabilities shot up from 25% to 80%. And this couplet did produce a tornado.
-Stormy Surge
Despite the known limitations/DA issues with AzShear as lines/convergence zones move orthogonal to radar radials, TORP was able to correctly identify (with high confidence) a tornadic signature near the RDA. -QLCS
Had a line of semi-organized storms cross multiple radials of beam blockage (as evident from KDVN radar). As this occurred, AzShear pattern associated with storms maintained character (bottom image/2044 UTC). No TORP object was created as I hypothesized (i.e. as real/artifact “combined”). -QLCS
AzShear exhibits a “blocky pattern” while dual pol shows evidence of a hail core resulting in side lobe contamination for this storm in the DVN forecast area on the afternoon of April 16th.
Posted by Rigel.
TORP tried identifying an area with low reflectivity southeast of KDVN at 2040z seemly outside of any storms. TORP peaked at 38% at this time.
Looking at the AzShear data, the pattern look like a wind farm with the blocky data. Fortunately TORP was only elevated for one scan.
-Stormy Surge
An interesting example of beam blockage filtering where an area of higher reflectivities bisecting the beam blockage was assigned a storm identification after the spurious values of AzShear was filtered out while those in the area of lower reflectivities were not.
Posted by Rigel
During today’s real time case, one line of storms drifted off into the extreme northeast corner of our CWA (DMX). This corner reported meteorological echoes at about 150 km away (just shy of TORPs max effective range of 160 km). At the southern end of this line, a convincing hook signature with an admittedly broad mesocyclone caught our eye.
Despite this, TORP was not creating any objects along this line with our selected radar (KDMX). Upon selecting the option to overlap other objects generated from surrounding radars, other objects appeared north of the hook in question, but not over it. This was a little concerning as this the sort of feature I would expect to generate at least a low probability object. But this issue is not surprising considering the range away from any of the surrounding radars and how lofted the data is.
This issue will certainly pose a challenge in areas where there are large distances between nearby radars.
-Wx Warlock
