Been watching the convection over northeast CO, and although the general trend of the severity of the convection is downward, the over-shooting top algorithm continues to ping over this area. This highlights that although the storms may not be producing severe weather, i.e. hail and/or wind, they could be significant rain producers and should continue to be monitored.

-JB

Watching trends in the probability of severe over northeast CO indicates a significant downward trend in prob severe with the low-lived storm that went through DEN. This occurred as the local office allowed the warning expire and the reflectivity signatures were decreasing as well. Provided confidence in letting the warnings expire.

-JB

Remember that screen capture of the 90% probability of convective initiation over Lawrence County, IN at 2130Z? By 2248Z, a decent cell had popped up in the NE corner of the county. Not sure if this necessarily verifies the product or not (after talking with the product’s contact here), but it does instill some confidence on using this product in the future.

~Linda

As of around 23Z we have switched over to CI for overnight detection. The false detections appear to increase once this switch happens. There still appeared to be some utility though as it highlighted area over southeast WY that developed, but one would need to use it with caution overnight.

-JB

The long-lived supercell that moved from the DEN area into northeast CO appear to be weakening as of 2330Z and the forecast simulated satellite data did well in forecasting not only the initiation of the convection, but also in the early demise in northeast CO.

-JB

I was using the Overshooting Top application and it showed one over the one storm for a couple of updates.  This led me to believe it had a strong updraft and then I looked at Prob Severe and it also trended up so I was going to issue a severe t’storm warning.  Now I want to see if this verifies.  ~ Vollmar

WRF Simulated Satellite imagery from around initiation time. Initiation time for the simulation was running about 30 to 60 minutes delayed from reality. Not Good but Not bad if the WRF data arrived more than 1 hours early. I also want to point out that it did capture the main storm of the day and roughly the correct placement for initiation.

First hints of initiation in Reality 1915Z.

First hints of initiation in WRF Simulation 20-21Z time frame.

Grant H.

Attempting to give a mesoscale environment update for my warning partner, I pulled up all of the LAPS products available in the 800×800 domain. The 20Z run is the latest available data and the ongoing storms (as of 2230Z) are depicted to be in a decent region of surface CAPE (>2000 J/kg), practically no CIN, and high pockets of surface and 2-5km instantaneous updraft helicity on the front edge of the broken line of convection. When I analyzed the LAPS’ max base reflectivity product and compared it with real-time MRMS composite reflectivity, it does okay in the 2.5-hour forecast in depicting a general region of convection stretching from east-central Illinois ESE toward the IN/OH/KY borders. The model is spatially displaced slightly but at least captures the general overview of the current setup.

Moving forward to the 4-hour forecast (00Z), LAPS forecasts the following:

If LAPS data is to be used to enhance near-term mesoscale forecasting, I personally would like to see some additional fields, such as wind, etc.

~Linda