Here is an attempt to show how a circulation may evolve over time and become stronger and tighter (increasing rotation rate) however the single radar AzShear does not help the user identify the increase in shear rates. The merged product AzShear was even more nondescript with its weaker appearance of the circulation.

It would be helpful to have some way to better visualize the change in shear over time in the AzShear products, either with a trend line or a different color curve.

When we are making warn/don’t warn decisions, changes of just a few kts rotation velocity may tip the scales, the AzShear product as it is now does not provide the resolution/detail for these changes.

SRM – 2122, 2124, 2126, 2128 UTC

KMXX AzShear (Top), Merged AzShear (Bottom) – 2122, 2124, 2126, 2128

— SCoulomb

Ultimately, AZ Shear has a lot of potential value in warning operations. It is really good at highlighting areas that need immediate investigation. Notice in this case how AZ shear maxima are present along a segment of the the storm that has begun to bow. Additionally, it has highlighted an area of rotation along the QLCS. Within a warning environment, I could foresee it increasing lead time on warnings because your attention is gravitated immediately to specific areas of AZ shear maxima. One thing I think would be of great benefit is making some of the az shear values closer to zero transparent, so that it can be easily overlaid on velocity products. In this case, I would also recommend using a different color scale than red because it will end up blending in with the velocity data.

South Beach

Single radar AzShear may be a game-changer for identifying the quick mesovortex spin-ups along a squall line. QLCS events remain one of the most challenging for radar meteorologists and any help in identifying these features could add needed lead time and/or confidence to the warning decision. Just being able to discriminate which circulation is most intense along a line would be sufficient argument to move this product into operations but the added benefit of early identification and consistent tracking of these features should get the attention of decision-makers.

— SCoulomb

Although SAILS scans are great for base data interrogation, it does cause issues with derived products such as the layered AzShear from a single radar. Here both the 0-2 and 3-6km products have previous scan data still present. This caused the AzShear feature to “split apart” while the circulation itself remained in tact. This seemed to be more of an issue with the 0-2km product but also impacted the 3-6km one.

For some forecasters this may not be a big deal at all but for others having to process in their mind what is going on with the product seemingly split a circulation for no reason can really throw them off or cause unneeded mental anguish (as minor as it may be). In a highly stressful situation such interruptions can mount up over time increasing fatigue or cause forecasters to no longer consider looking at a particular product. I have seen some even turn off SAILS by default so they don’t have to deal with the idiosyncrasies it may cause. This could reduce lead time or cause someone to miss an important feature for “convenience” sake and not for some other valid reason.

— SCoulomb

Two new circulations appeared south of the main storm of interest. AzShear provided good SA in identifying these as needing investigation. Also clearly depicting which one was more intense and needed to be looked at first (the further south one).

— SCoulomb

Obvious issues with merged AzShear not seen in the single radar product: multiple reflections of the velocity gradient along the leading edge of the convective line. The single radar AzShear maintained a single, more coherent circulation.

The single radar AzShear provided a cleaner look at the meso near the AL/GA border. The merged product had some bad data that made it look less representative and would likely cause confusion or loss of confidence by the forecaster.

Merged AzShear (L), KMXX AzShear (UR), vel (LR)