This study examines the spatial and quantitative influence of urban factors on the surface air temperature field of the medium-sized city of Szeged, Hungary using of mobile measurements under different weather conditions between March 1999 and February 2000. This city of about 160,000 is situated in a low, flat flood plain. Efforts concentrated on the determination of spatial distribution of mean maximum urban heat island (UHI) intensity with special regard to land-use features such as built-up ratio, sky-view factor, building height, water surface ratio and distance from city centre as well. In both (heating and non-heating) seasons the spatial distribution of UHI intensity field had basically concentric shape with local irregularities. Nevertheless, the mean maximum UHI intensity reaches more than 2.1°C (heating season) and 3.1°C (non-heating season) in the centre. We have been determined relationships between the above mentioned land-use parameters and mean max. UHI intensity by means of multiple linear regression analysis. The model is based on two linear regression equations which are calculated for the studied periods. The model equations show strong (0.1%) connection between UHI intensity and land-use factors. As the measured and predicted mean maximum UHI intensity patterns show, there is a clear connection between spatial distribution of urban thermal excess and examined land-use parameters, so these parameters play a very important role in the evolution of the strong UHI intensity field over the city. However, the role of water surface is negligible in this case. From the above mentioned parameters the sky-view factor and building height were the most determining factors which are in line with urban surface energie balance. Therefore, in the future, by means of our model there will be possibilities to predict mean maximum UHI intensity in other cities which have similar quasi-invariable land-use features such as Szeged. On the other hand, these results can be applied to develop appropriate urban surfaces in the light of human thermal comfort.