Thunderstorm occurrence at ten sites across Great Britain over 1884–1993

Abstract

The UK Met Office's Daily Weather Reports (DWR) contain extensive logs of UK thunderstorm activity. To date, only a very small fraction of these data have been digitized as part of the MIDAS dataset, and exclusively after 1950. Using the recently‐scanned UK Met Office Monthly Weather Reports (MWR), which are based on a subset of the observations that form the DWR, we here provide digitized data and a summary of thunderdays from 10 long‐running British stations over the period 1884–1993. The data are presented ‘as is’, with no attempt to provide any corrections or calibration. For 4 of the 10 stations, thunderday observations were discontinued at various times between 1949 and 1964, and it is necessary to switch to a neighbouring station in order to continue the series. Approximately half the series exhibit sharp drops in thunderdays at various points between 1960 and 1990, although none are coincident with known station changes. Comparison with nearby MIDAS stations suggests the low thunderdays are the result of changes in observing practice, rather than genuine changes in thunderstorm occurrence. These potential data issues limit interpretation of the long‐term trends. However, it can nevertheless be concluded that none of the stations show the expected increase in thunderdays as a result of the rise in surface temperature over the 20th century. In order to provide more quantitative determination of the long‐term trends in thunderstorm occurrence, we advocate further digitization efforts to recover the data from the numerous stations in the MWRs, and subsequent analysis of the common signals across neighbouring stations.

Exploring relationships between weather patterns and observed lightning activity for Britain and Ireland

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‘Days with snow’: an appraisal of snowfall records made by Climatological Observers Link members

“…Is it possible to derive time series of SSF that are comparable to human observations? While automation and part‐automation have had an effect on the accuracy of thunder‐days statistics (Valdivieso et al ., 2019), voluntary observations have been used to supplement ‘official’ observations (Burt, 2020).…”

Two hundred years of thunderstorms in Oxford

“…Monthly and annual totals of ‘days with thunder heard’ for Oxford were published in the Monthly Weather Report ( MWR ) 1884–1993 (when the MWR ceased publication), and these together with other sites were analysed by Valdivieso et al . (2019). However, monthly values extracted from the MWR were normally lower than those taken from the Radcliffe Results .…”