An error has been found in the calculation of Froude numbers (FrH and FrL) presented in Fig. 9 of Lyza and Knupp (2018). The corrected Fig. 9 is shown below. This error was discovered during preparation for the submission of an upcoming article that utilizes this dataset. The code for calculating the values of FrH and FrL did not account for the wind speed data being provided in knots in the RAP sounding files. Correction of this error and utilizing the correct units reveals no meaningful changes to the findings of Lyza and Knupp (2018). Values of FrH are still greater than one for the vast majority of Southern Cumberland System (SCS) tornado cases evaluated, and magnitudes of FrL are still well below one for all evaluated cases.
RUC and RAP sounding scatterplot of FrH vs FrL at Anniston, Alabama (187 m ASL), for the most recent available 0-h model forecast times prior to SCS tornado events from 2006 to 2016. The 150-, 250-, and 350-m heights are used to display potential variations in Froude values along the SCS. The dashed lines indicated FrH values of –1 and 1. Note that all FrL values are of magnitude <1.
Citation: Monthly Weather Review 147, 9; 10.1175/MWR-D-19-0165.1
RUC and RAP sounding scatterplot of FrH vs FrL at Anniston, Alabama (187 m ASL), for the most recent available 0-h model forecast times prior to SCS tornado events from 2006 to 2016. The 150-, 250-, and 350-m heights are used to display potential variations in Froude values along the SCS. The dashed lines indicated FrH values of –1 and 1. Note that all FrL values are of magnitude <1.
Citation: Monthly Weather Review 147, 9; 10.1175/MWR-D-19-0165.1
RUC and RAP sounding scatterplot of FrH vs FrL at Anniston, Alabama (187 m ASL), for the most recent available 0-h model forecast times prior to SCS tornado events from 2006 to 2016. The 150-, 250-, and 350-m heights are used to display potential variations in Froude values along the SCS. The dashed lines indicated FrH values of –1 and 1. Note that all FrL values are of magnitude <1.
Citation: Monthly Weather Review 147, 9; 10.1175/MWR-D-19-0165.1
REFERENCE
Lyza, A. W., and K. R. Knupp, 2018: A background investigation of tornado activity across the southern Cumberland Plateau terrain system of northeastern Alabama. Mon. Wea. Rev., 146, 4261–4278, https://doi.org/10.1175/MWR-D-18-0300.1.
