Temporal distribution of atmospheric pressure, the stimulus impact of atmospheric pressure greater than 1015 hPa or below 985 hPa were the aim of this study. Frequency of occurrence and probability of interdaily pressure changes were stated and relationship between these changes and types of atmospheric circulation according to Litynski were analyzed. One hour values of atmospheric pressure from station Ursynów WULS-SGGW of the period 2011–2015 were used in the calculations. Based on the study found that in Warsaw atmospheric pressure of stimulus impact can occur in any month with the probability between 0.2% and 19.1% for pressure greater than 1015 hPa, and between 0.1 to 3.4% for pressure lower than 985 hPa except two months: June and August. The interdaily changes in atmospheric pressure may reach about 24 hPa and the frequency of occurrence „strong” stimulus caused by these changes in each month were from 1% to 16% while frequency of occurrence „very strong” stimulus from 2% to 8%. Among of the synoptic situations, the most important for stimulus of pressure changes are cyclonic situations especially for the inflow of air from the north-western sector (NWC).