abstract: In the paper series of maximum (Tmax) and minimum (Tmin) temperatures were analysed. The series were taken from three meteorological stations of IMGW – Elbląg, Olsztyn, Suwałki and also from the UWM Research Centre at Tomaszkowo, 6 km from Olsztyn. The analysis of extreme thermal conditions and its trends in north-eastern part of Poland was made. A comparison was made of characteristic days in 2006 and in the periods of 2001-2005 and 1951-2005. The results showed that Tmax had a mostly increasing tendency (without VI and IX). Tmin was characterized by lower significance for linear trends only in Elbląg and Olsztyn.