GRevel3 Hail indicator

[Dave Gallaher]

Interesting--I had just come out of the grocery in Huntsville and saw the approaching cb with nicely shaped precip shaft. The core lay right on my path back home, so a 'punch' was required.

Good heavy rain, strong winds, and hail up to about 3/4" (most was pea size) and inundated streets were the result. One frightened driver actually blocked traffic by stopping under a tree to protect her new-looking car, then ran a red light to esape the 'threat' to her new finish.

When I arrived home, I booted up GRL3 to watch. No hail indicator showed up until it was well past my location. Even trying to figure in the five minute delay, it seems like it was off a couple miles.

I guess the margin of error is to be expected?

 

[rdale]

It's not running GR algorithms, that just displays the NWS 88D hail output. You'll find much better results with the GR2AE output.

 

[Greg Stumpf]

The GR2AE gridded hail algorithm is the same HDA logic applied to the reflectivity profile at each grid point, rather than the vertical dBZ core in a storm cell. Both algorithms were developed at NSSL, Gibson adapted the gridded algorithm for GR2AE.

 

[Zac Flamig]

Also if you don't want to get GR2AE you can view the generated product on the web on NSSL's website at http://www.nmq.nssl.noaa.gov/. You'll have to go to Mosaic3D Derived and then select MEHS as the product.

 

[Greg Stumpf]

Also if you don't want to get GR2AE you can view the generated product on the web on NSSL's website at http://www.nmq.nssl.noaa.gov/. You'll have to go to Mosaic3D Derived and then select MEHS as the product.

One further note...the MESH grid available here, and on

http://wdssii.nssl.noaa.gov/geotiff_new/

Are based on gridded reflctivity profiles that are created by merging multiple radars. This provides a much more robust solution than a single-radar MESH, with storms being multiply-sampled, and cones-of-silence and far range storms being filled in by other radars.