Frontal Processes in the Saint Lawrence River Valley During the WINTRE-MIX Field Program

The Saint Lawrence River Valley (SLRV) and Lake Champlain Valley (LCV) front is a key factor influencing the weather of southern Quebec, southeastern Ontario, and portions of northern Vermont and New York. In this study, an analysis of SLRV-LCV frontal processes is performed using data retrieved during intensive observation periods (IOPs) of the WINTRE-MIX (WINter precipitation Type REsearch MultI-scale eXperiment) field campaign, occurring from 1 February through 15 March 2022. In particular, case studies selected from the Intensive Observation Periods during the WINTRE-MIX field campaign are presented. These case-study analyses consist of a unique synthesis of high-resolution WINTRE-MIX observations and ECMWF (European Centre for Medium-Range Weather Forecasts) Reanalyses v5 (ERA5). As a result, the author gains new insight into the synoptic-scale and mesoscale environments of frontal processes occurring in the SLRV and LCV regions. Key frontal features are found within the SLRV and LCV frontal case studies that have been shown in previous research, such as a frontal strength that is maximized near the surface, vertical motions found directly above the low-level frontogenesis, high static stability in the frontal zone, and the presence of strong vertical wind shear. One particular SLRV and LCV front case study is hypothesized to illustrate features of SLRV frontogenetical modulation of precipitation.