Abstract:Using the daily observation data from the national meteorological stations in Henan Province, spanning from November of each year to March of the following year, from 1991 to 2020, a comprehensive survey was conducted on single-station and regional occurrences of low temperature rainfall/snowfall and freezing (LTRSF) days. The temporal and spatial distribution characteristics of LTRSF days in Henan Province were statistically analyzed by mathematical statistics and synoptic analysis methods. Furthermore, the large-scale circulation patterns conducive to LTRSF were classified, and forecast indicators were established. The results show that: the number of stations with LTRSF in the past years showed an overall decreasing trend, but it was not significant. The average annual number of stations was 882.4, with the highest number of stations occurring in 2001 and the lowest in 2007. The cumulative monthly average number of stations was 5294.2, with the highest number of stations occurring in January and the lowest in March. The longest duration days of LTRSF in a single station were concentrated in 5~6 days, accounting for 72.9%. Stations located in the western mountainous regions experience more frequent and longer durations, while those in the eastern part of Puyang have fewer occurrences and shorter durations. Stations in the Nanyang Basin and the eastern part of Shangqiu experience fewer events but with longer durations. Regionally, an average of 11 LTRSF days occured annually, and the duration of these regional events was primarily concentrated between 1 and 2 days, accounting for 77.4% of all regional events. The daily minimum temperature and daily minimum ground temperature and 925~700hPa temperature ≤ 0 ℃ and T500 ≤ -12 ℃ can be used as the forecast indicators of LTRSF. The 500 hPa circulation field that generates LTRSF is categorized into two major types: blocked and non-blocked. The surface cold air path is categorized into four major types: west road, northwest road, middle road and east road, with the northwest type accounting for the most 48%, followed by the middle type accounting for 27%.