Since convection has not fired up yet in the Tennessee/Ohio Valleys, I was able to spend some time analyzing the pre-storm environment with the products we’re testing this week. The first on the list is the NSSL-WRF simulated IR/WV satellite product; I pulled up a four-panel with simulated on the left and actual on the right (below). As of ~1845Z-19Z, the simulated imagery was depicting isolated convection across southern KY and middle TN too soon but not necessarily entirely inaccurate. It is accurately honing in on the cloud cluster centered over IN-IL-IA/MO border, albeit overdoing the coverage and coolness of the cloud temps, as has been observed all this week. Interestingly, it is not picking up on the cirrus overspreading the Ohio Valley and into TN. Accounting for all of this, I can adjust accordingly and remain confident in using this product to develop a mesoscale forecast.

Moving to the next item on the list, I pulled up a four-panel of the NearCast analysis products with 500mb theta-e in the top left, 780mb theta-e in the bottom left, theta-e difference in the top right, and 900-700mb PW in the bottom right (below). A surge of mid-level instability can be seen diving into TN and is also evident in the difference product with the gradient diagonally stretched from the NW corner of TN to the SE corner. PW values/moisture surge matches with where storms are quickly firing up in western and south-central KY. When analysis data is available for these NearCast products, I really like to use these to diagnose and forecast.

Next, I loaded the same four-panel with the NearCast forecast and took a screen shot of the 2-hour forecast (21Z, below). Unfortunately, missing data over the region of interest exists with the 500mb theta-e and theta-e difference products. However, I can still see the lower-level instability and moisture axis draped across western KY into TN in the 780mb theta-e and 900-700mb PW, respectively. Given the success of these products so far, I have good confidence in utilizing the forecasts to accurately predict where the greatest threat will be, given other atmospheric conditions line up for convection as well.

Looking at GOES-14 SRSOR vis imagery and overlaying the CI product, a 60% probability popped up in western KY (below) and within a half hour, storms developed in the vicinity. There was a false alarm 60% probability just to the west of Paducah, KY, probably due to the thin cirrus streaming over a CU field there. In OHX’s CWA, no reliable indications of convective initiation has appeared yet. As for the SRSOR product, I am once again very pleased to have this data available to more accurately assess and see the evolution of the regional atmosphere.

Below, I overlaid OTD on IR SRSOR imagery and thus far, no detections.

~Linda