Assessing Dew Point Depression as an Indicator of Wintertime QLCSs in NC

Quasi-Linear convective systems (QLCSs) are lines of hazardous thunderstorms. Moist convective processes in the atmosphere play a large role in the development of these storms. The goal of this research is to assess the feasibility of using Dew Point Depression (DPD) as an indicator for QLCS occurrences across North Carolina during the Winter months (December through February). For this study, we chose four QLCS storm occurrences and analyzed hourly dew point temperature and air temperature data collected from four of the NC Environment and Climate Observing Network (ECONet) stations. We compared DPD values, taken from three days prior until the day of storm onset, to the climatological (20 year) DPD averages. We found that for all four of the storm events, there was a statistically significant difference between climatological and storm DPD values for the two-day window before storm onset. We also found that for three of the four storm events, DPD values reached a minimum value one day before storm onset and stayed low until storm onset. These results suggested the usefulness of DPD metrics as good indicators of QLCSs, so we further analyzed the fluctuations in DPD leading up to storm onset by repeating the process for four more QLCS storm occurrences. These results could be used to better help forecasters in predicting severe storm events. Future research could incorporate more QLCS events and assess greater time-frames before storm onset to further determine the usefulness of DPD as an indicator of QLCS occurrences.