 This study examined the seasonal variability of the surface urban heat island, Suhi, in the Tehran metropolitan area, Iran. It found that an inversion of the Suhi phenomenon occurred at daytime with the maximal value of urban rural land surface temperature, LST, difference of –4K in March, while the maximal value of Suhi at nighttime yielded 3.9K in May. Additionally, the study showed that the relationship between all surface properties with LST possessed large seasonal variations, and thus, using these relationships for Suhi modeling may not be effective. This article was authored by Cyrus Hashimi, Kihei Owang, Ali Darbashi, and others.