3D VAR Composite Updraft seems to be relatively helpful in confirming the strength of a storm.  However, with some quick pulse storms, the 3D VAR data seemed to lag behind a little.  In the series of images below you can see that the best Updraft strength noted at 22Z (upper right panel of 3rd image) seems to better match radar data from 2154Z (1st image below) rather than 2159Z (2nd image below).  So there seems to be a slight lag with 3D VAR data catching the stronger updrafts in pulse storms, but that’s probably to be expected with this type of storm.

2154Z:

2159Z:

2200Z:

AMS

At 2215z…strong storm was located over Camden County.  3DVAR products indicates updraft maximum values around 13 m/s with an updraft helicity near 33 m/s2.  Visible satellite imagery (second image) is also showing a broad area of higher clouds…possible overshooting top…over Camden County.  Visible satellite image is verifying the updraft information.  AMS/Hovis

19Z HRRR 2hr field indicated that thunderstorm coverage would increase from isolated to scattered along the advancing cold front.  This coverage is expected to remain scattered as it tracks toward the coast.  Nunez

Total wind picked up a weak perturbation on the wind field between 2025Z and 2050Z.  By 2050Z, helicity signature developed in conjunction with the strengthening updrafts/stronger reflectively.  Nunez

At 2032z…storm was pushing offshore from St Johns County in Fl.  The CTC product indicated strong cooling rates approaching -20 DegC/15 minutes associated with that storm.  There was a short period of time when we did not receive any products.  However…the radar showed a stronger storm with increased lightning activity by 2112z.  AMS/Hovis

3DVAR total wind and updrafts did a great job picking up the strong-severe winds over Berkeley county.  Total wind increased at 1945z through 2000Z while updrafts continued to strengthen.  Between 2005-2010Z, updrafts weakened while the total winds depicted stronger winds descending; helicity was 50+m/s .  Nunez

Two images are shown here.  On the left, a line of storms extends along the South Carolina coast and into portions of southern Georgia at 2014Z. Earlier at 1945Z, on the right, the UAH Convective Initiation product showed 3 areas of 60%.  Initiation was predicted along and just ahead of an outflow boundary, and just off the coast oriented west southwest to east northeast.  The product performed very well, with around 30 minutes of lead team for the updrafts that exhibited +35dBZ.

Cloud to cloud lightning was observed in a very weak storm in Osceola County.  pGLM flash rates are observed in the upper right and lower left images depicting the cloud to cloud lightning.  Cloud to ground lightning was not observed with this storm as depicted by the absence of strikes in the lower right panel.  This data proves that this weak storm had an updraft strong enough to produce cloud to cloud lightning but not cloud to ground lightning.

I feel that adding cloud to cloud lightning data will really help storm warnings, fire weather applications, aviation forecasts, etc. if added as a baseline product for WFOs because we’re obviously missing a lot of lightning data not only in weak convection as this example shows but in strong/severe storms as well.

AMS/Hovis

Storm that prompted the Beaufort/Charleston/Colleton counties warning showed near 40kt as the gust front advanced east.  Interestingly, the 3DVAR depicted a total wind field that simulated the potential of winds descending behind the advancing storm.  This field is a great asset especially if the warning forecaster encounters radar limitations during the warning processes.  nunez

updrafts have been weak across the line of thunderstorms.  We are monitoring an isolated storm over eastern Jasper county that was approaching severe strength.  MESH trends:  max 1″ center occurred for one scan while the trend was less 3/4″.  Legacy hail algorithm:  consistent max values at 1″ with one 2″ estimate.  nunez