Hail/Lightning papers
Canada's Hail Climatology: 1977 - 1993 David Etkin Meteorological Service of Canada, Institute for Environmental Studies, University of Toronto
And
Soren Erik Brun Department of Geography University of North Carolina, Chapel Hill Paper Series – No. 14
Abstract
The last national hail climatology of Canada was based upon the 1951-80 time period. However, from 1977 to 1993, many more stations reported days with hail than prior to 1977. As a result, a more spatially detailed analysis is now possible. Unfortunately, after 1993 the observing network began to be replaced by automatic stations that do not report hail, and therefore a mesoscale analysis can only effectively use the time period of 1977-1993. Due to the fact that ice pellets have often been recorded as hail, this analysis restricted itself to the warm months of May to September. The current national hail climatology is broadly similar to the previous one (with a few notable differences) but is much richer in spatial detail. The highest hail frequencies occur in interior British Columbia and Alberta. Topography appears to be a significant control on patterns of hail occurrence.