The object of the study is the maximum daily air temperature during the months of the year over 1991-2016 by the data of 186 meteorological stations of Ukraine. Extreme values of the maximum daily temperature equal to or exceeded their 95th (Tmax95p and above, ºС) percentile were taken as extreme. The article sets the dates (137 cases) of extreme values of maximum air temperature on more than 60 % of the territory. For these dates, 13 meteorological parameters were selected: average, minimum, and maximum air temperatures; average, minimum and maximum relative humidity; station and sea-level pressure; average, maximum (from 8 synoptic hours) wind speed; rainfall; height of snow cover. The purpose of this work is to determine the correlation coefficient (K), in particular, statistically significant (K≤-0.6, K≥0.6), on these dates between selected meteorological parameters at 186 meteorological stations of Ukraine for 1991-2013. The density of the cases of statistically significant dependence between the meteorological parameters in extremely warm days in separate seasons is determined. In extremely warm days, meteorological parameters and areas with statistically significant correlations at K≤-0.6 were detected: T and F (focally in southern and some western regions with significant density) − in winter; T and F (with the highest density ubiquitous or almost ubiquitous), P and V (in a large number of regions, usually west or right-bank, but with less frequency) − in the transition seasons, and in the autumn between − T and F (in the south with smaller density) and P and F (in some areas of the north, northwest, west, lower east). In all seasons, such a correlation between other meteorological parameters had a focal distribution, usually with a smaller density. In these days, a focal distribution with a small frequency of dependencies at K≥0.6 was found between the meteorological parameters detected (F and V in transition seasons, T and F in winter), except for similar ones. However, such dependence is observed between T and V in some regions in winter and autumn and in some areas of south, southeast, east with a smaller density. The study of the maximum daily temperature is relevant, because from the level of natural hydrometeorological phenomena it is accompanied by dangerous phenomena, negatively affecting the weather dependent industries.

The presented article is devoted to the study of modern trends in the spread of ice deposits on the territory of Ukraine in the last thirty years of 1991-2020 (new climate standard) relative to the period 1981-2010. recommended by WMO. The conducted research is related to the research work on the study of climate change carried out at the UkrSMI. Question status. Despite certain achievements in the study of the distribution of ice-frost deposits in the territory of Ukraine in the past, the task of determining the existing trends and subsequent changes in their distribution under the influence of climate change remains unresolved. The purpose of the study was to determine the current state and features of the distribution of the field of ice deposits on the territory of Ukraine with the identification of centers of increase and decrease in the average amount of such deposits, as well as trends relative to another observation period. Materials and methods. Data of actual instrumental observations of ice deposits at all meteorological stations of Ukraine for two periods 1991-2020 and 1981-2010 were used for processing. The main research methods were physical-statistical with the determination of the normalized values of the number of cases of such deposits and cartographic with the visualization of the results. The information obtained is not only informative, since it reflects the current trends in the distribution of one of the types of ice-frost deposits, which are adverse weather phenomena, but also allows you to plan the work of weather-dependent industries in more detail, ensuring their uninterrupted operation. Main results. It has been established that most of the deviations of the average number of ice cases for the study period relative to the period of 1981-2010. were insignificant, but in some areas during the cold season, especially in winter, they reached higher values. values. It has been established that in January and December there is a predominance of positive deviations of the average number of ice cases in Ukraine. Most of the centers of positive deviations are based on the territory of the western region from Volyn. Rivne and Zhytomyr regions to the Carpathians, as well as in the north of the Chernihiv and Sumy regions, as well as in a number of central regions from Vinnitsa to Poltava and Dnepropetrovsk regions. Also, noticeable foci of such deviations are observed in the north and east of the Kharkiv region, as well as in the north of the Luhansk region. They are noticeable in the south of the country. In February and March, foci of negative deviations were most often encountered. The most pronounced of them were observed in the western region in the territory from the Zhytomyr region to the Carpathian region, as well as in some central regions. In February, a focus of positive deposits was discovered in the north of the Chernihiv region. In April-October, the field of ice deposits for 1991-2020. compared to 1981-2010 practically did not change. In November, an increase in the number and spatial distribution of positive deviations of the average amount of ice deposits was revealed. They were mainly distributed in the central regions from Vinnitsa to the Poltava and Dnepropetrovsk regions, as well as in the east of the Kharkiv region and the north of the Luhansk region.