Dallas Weather & Climate — The Honest Truth About DFW Seasons

Hot. NOAA's 1991-2020 climate normals for DFW International Airport put the average high at 92°F in June, 96°F in July and August, and 89°F in September. The airport averages about 106 days a year at 90°F or above and about 20 days at 100°F or above, most of those in July and August. Dallas is less humid than Houston (the average July dew point is about 68°F at DFW Airport, against about 73°F at Houston's Bush Intercontinental Airport), but the heat still demands planning: schedule hard outdoor exercise for early morning from June through September. Air conditioning is not a luxury here. It is infrastructure.

Yes. In the National Weather Service Fort Worth office's records for North and Central Texas from 1950 to 2025, April and May account for more than half of all tornadoes, though they have occurred in every month. On the night of October 20, 2019, an EF-3 tornado with peak winds near 140 mph tracked about 15.75 miles from northwest Dallas, roughly along Walnut Hill Lane, into Richardson, according to the NWS damage survey. The most important thing newcomers can do is learn watch versus warning. A tornado watch means tornadoes are possible in and near the area. A tornado warning means a tornado has been sighted or indicated by weather radar, so go at once to an interior room on the lowest floor, away from windows. The City of Dallas tests its outdoor warning sirens at noon on the first Wednesday of each month, weather permitting. The sirens are meant for people outdoors, so indoors rely on phone alerts or a weather radio.

Mild on most days, with occasional hard freezes and ice. NOAA's 1991-2020 normals for DFW Airport put the average January high at 57°F and low at 36°F, with about 29 nights a year at 32°F or colder and about 1.6 inches of snow a year, most of it in February. The bigger hazard is freezing rain and sleet: bridges and overpasses ice first, and roads can stay dangerous for a day or more. In February 2021 (Winter Storm Uri), DFW Airport fell to -2°F on February 16 and stayed at or below freezing for 139 straight hours from February 13 to 19, per the National Weather Service; the official record low is still -8°F, set on February 12, 1899. Across the state, many power plants and natural gas facilities could not operate in the cold, which led to prolonged customer outages.

Spring and fall. October is the first month since April with an average high below 80°F: NOAA's normals for DFW Airport put it at 78°F with a 57°F low, and the State Fair of Texas typically runs from late September into mid-October. October is also the second-wettest month on average (4.4 inches, behind May's 4.8), so keep an umbrella handy. April (76°F high, 55°F low) is mild but falls in the peak severe-storm season, and November (67°F, 46°F) is cool. Summer heat and winter cold squeeze these comfortable stretches, which is why residents plan so much around them.

Dallas is on the grid managed by ERCOT (Electric Reliability Council of Texas), which covers about 90 percent of the state's electric load. Texas is the only state with its own grid, largely separate from the grids that serve the rest of the country. As in Houston, most Dallas addresses are in the competitive retail market: Oncor delivers the power, but it does not sell electricity or send bills. You choose a retail electric provider, and the Public Utility Commission's PowerToChoose.org lists offers by ZIP code (a ZIP code with no plans listed may not be open to competition). Read each plan's terms before you sign, since plan types and contract lengths vary. After the February 2021 winter storm, Senate Bill 3 required power plants and transmission facilities in the ERCOT region to weatherize, and ERCOT now inspects them. Keep basic supplies at home anyway: Ready.gov recommends water (one gallon per person per day) and non-perishable food for several days, a flashlight, and a phone charger with a backup battery.

It does flood, though the pattern differs from Houston's. Dallas is far inland, so hurricane storm surge is not a factor, but heavy thunderstorms can flood streets, underpasses, creeks and low-water crossings quickly, and May and October are the wettest months on average. The Trinity River runs through central Dallas between levees. Before you buy or rent near a creek or drainage channel, look the address up on FEMA's Flood Map Service Center (msc.fema.gov) and ask about its flood history. FloodSmart, the federal flood insurance program's site, notes that most homeowners insurance does not cover flood damage. And if water covers a road, turn around: the National Weather Service warns that 12 inches of rushing water can carry away most cars.

NOAA's official 1991-2020 climate normals do not include a count of sunny days, so this guide does not quote one. What the normals do show for DFW Airport is how much of the year runs hot: about 106 days a year reach 90°F or above, about 20 reach 100°F or above, and the average high stays above 80°F from May through September. Rain averages 37 inches a year, with May (4.8 inches) and October (4.4 inches) the wettest months and July (2.1 inches) the driest. Those summer months take planning to enjoy outdoors safely.