# Comparing Winds near Tropical Oceanic Precipitation Systems with and without Lightning
## 3 Results
### Lightning Analysis
#### 3.2.2 Trends versus Precipitation Rates  
The general results presented in Tables 2-4 were interrogated more deeply by examining how differences in categories behaved as functions of rain rate and lightning flash rate. For this analysis, rather than examining absolute wind speeds, the mean wind speed along each track was first subtracted from the wind speeds in each raining feature along the same track. This was done to determine the extent to which the results in Tables 2-4 were affected by the influence of larger-scale environmental winds. Figure 5 shows the results for CYGNSS FDS and ASCAT mean wind differences as functions of IMERG precipitation rate. Whether the precipitation is associated with lightning or not, CYGNSS winds start roughly 1 m s\({}^{-1}\) above background, indicating that precipitation is associated with stronger winds. For very light rain rates (\(<\)1 mm h\({}^{-1}\)) CYGNSS does see slightly higher wind speed differences when WWLLN lightning is present (Figure 5a), but this trend quickly reverses as rain rate increases and winds without WWLLN lightning and maintain a \(\sim\)0.5 m s\({}^{-1}\) advantage for rain rates above \(\sim\)5 mm h\({}^{-1}\). Wind speed differences increase slowly with precipitation rate after \(\sim\)5 mm h\({}^{-1}\) as well. For ASCAT winds (Figure 5b), the differences from CYGNSS are significant. Like CYGNSS, ASCAT wind speeds in precipitation start about 1 m s\({}^{-1}\) above background, and winds with WWLLN lightning are slightly stronger. However, unlike CYGNSS that \(\sim\)0.5 m s\({}^{-1}\) advantage for winds with lightning is maintained as rain rate increases until at least 15 mm h\({}^{-1}\), when the 99% confidence intervals between the curves \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Variable** & **Mean** & **99\% Conf. Int. (\(\pm\))** & **Samples** & **RCG \textgreater{} 10** & **Rain \textless{} 6 mm h\({}^{-1}\)** \\ \hline CYGNSS FDS & & & & **(Mean)** & **(Mean)** \\ with LIS (m s\({}^{-1}\)) & 8.36 & 0.02 & 154,517 & 8.57 & 8.22 \\ \hline CYGNSS FDS without LIS & & & & & \\ (m s\({}^{-1}\)) & 8.70 & 0.01 & 2,587,259 & 8.90 & 8.67 \\ \hline CYGNSS YSLF with LIS & & & & & \\ (m s\({}^{-1}\)) & 9.01 & 0.04 & 152,631 & 8.80 & 8.82 \\ \hline CYGNSS YSLF without LIS (m s\({}^{-1}\)) & 9.19 & 0.01 & 2,568,336 & 8.86 & 9.15 \\ \hline ASCAT with LIS (m s\({}^{-1}\)) & 8.90 & 0.09 & 11,664 & N/A & 8.65 \\ \hline ASCAT without LIS (m s\({}^{-1}\)) & 8.30 & 0.02 & 235,198 & N/A & 8.25 \\ \hline IMERG with LIS (mm h\({}^{-1}\)) & 3.43 & 0.04 & 154,517 & N/A & N/A \\ \hline IMERG without LIS (mm h\({}^{-1}\)) & 0.96 & 0.00 & 2,587,259 & N/A & N/A \\ \hline CYGNSS Std. Dev. with LIS (m s\({}^{-1}\)) & 1.02 & 0.03 & 4,394 & N/A & N/A \\ \hline CYGNSS Std. Dev. & & & & & \\ without LIS (m s\({}^{-1}\)) & 0.87 & 0.01 & 147,278 & N/A & N/A \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Summary statistics for winds and precipitation both associated and not associated with ISS LIS lightning. start to overlap. Wind speed differences above background also increase more sharply as precipitation rate increases (both with and without WWLLN lightning), compared to CYGNSS. Figure 5: (**a**) CYGNSS FDS wind differences as functions of IMERG precipitation rate, for wind observations associated with WWLLN lightning and those not. (**b**) ASCAT wind differences as functions of IMERG precipitation rate, for wind observations associated with WWLLN lightning and those not. (**c**) CYGNSS FDS wind differences as functions of IMERG precipitation rate, for wind observations associated with GLM lightning and those not. (**d**) ASCAT wind differences as functions of IMERG precipitation rate, for wind observations associated with GLM lightning and those not. (**e**) CYGNSS FDS wind differences as functions of IMERG precipitation rate, for wind observations associated with ISS LIS lightning and those not. (**f**) ASCAT wind differences as functions of IMERG precipitation rate, for wind observations associated with ISS LIS lightning and those not.