Building in Grayson County
Grayson County is in north central Texas, bounded by the Red River and by Fannin, Collin, Denton, and Cooke counties. Sherman, the county seat, lies about sixty-five miles north of Dallas and is part of the Sherman-Denison metropolitan area. The county covers 934 square miles.
Terrain is generally level with some low hills, at 600 to 800 feet. The north drains toward Lake Texoma and the Red River and has acidic Post Oak Belt soils with loamy or sandy surfaces, while the south has blackland soils. Precipitation averages thirty-seven inches a year. January lows average 30° F, July highs 96°, and the growing season is 227 days.
Grayson County was marked off from Fannin County on March 17, 1846, and named for Peter W. Grayson, attorney general of the Republic of Texas. The same act named the seat Sherman, after Gen. Sidney Sherman. Sherman became a Butterfield Overland Mail station in 1858. Railroads reached Sherman and Denison in late 1872, and the population jumped from 14,387 in 1870 to 38,108 in 1880. The county grew into a milling and market center but stayed mostly agricultural.
NOAA’s Storm Events Database lists 181 hail reports in Grayson County from 2016 to 2025, 144 of them an inch across or larger, with stones up to 2.5 inches. The same records show 93 damaging thunderstorm wind reports, with gusts up to about 90 mph, and 5 tornadoes. That is why a patio cover’s roof panels, fasteners and posts here are chosen for hail and wind, not only for shade.