This article is about typical and atypical Dallas weather. The latest weather information and forecasts can be found here.
The Dallas/Fort Worth Metroplex has its share of wacky weather, but for the most part, our seasons are predictable: hot in the spring, really hot in the summer, hot in the fall, and intermittently hot and cold in the winter. All kidding aside, here is some pertinent information for local gardeners, travelers to the region, or trivia buffs.
Typically, the hottest month is August, with June, July and September not far behind. The summer heat tends to taper off quickly in the first two weeks of October, when the high pressure that settles over the Metroplex gets pushed off by tropical storms coming in from the Atlantic.
The average number of days where the high is more than 100 degrees Fahrenheit is a mere sixteen, but in the middle of summer, that's no comfort. The exact number can vary greatly each year. Here is a table of the number of days in a given year:
- 2007: 05
- 2006: 42
- 2005: 18
- 2004: 01
- 2003: 19
- 2002: 01
- 2001: 08
- 2000: 46
The high heat of Dallas summers means a homeowner's highest utility bills will be in the summer, especially July and August. The heat can also take its toll on human life and pets. Do your outdoor chores in the early part of the day. Don't leave your pets outside without shade and unlimited water. Drink plenty of water and watch those especially vulnerable to heat illnesses, such as children and the elderly. Don't leave children alone in a car.
The average date of the first freeze is November 17 and the average date of the last freeze is March 14. Because of the heat island effect, rural areas can experience first freezes up to a week before the official area first freeze. Similarly, last freezes in rural areas can happen as late as a week after the official last freeze. First freezes have occurred as early as October 22 and as late as January 4. Last freezes have occurred as late as April 13 and as early as February 5. The area usually receives 750-850 chill hours each year.
It snows here most years, but the snow rarely sticks to the ground. So when you see it, enjoy it. It won't last. The most in twenty-four hours was 12.1 inches in January of 1964. In February of 1978, 13.5 inches fell during the month. It stuck to the ground that year.
Rain is another story. Dallas averages nearly 35 inches of rain a year, spread out nearly evenly throughout the year, although you wouldn't know it from the dry, hot summers. May and October get the highest amount of rain with five and four inches, respectively. July, August, and January get the least, averaging around two inches each, but those rains often fail to dampen the soil. The most rain in one month fell in April of 1922 when 17.64 inches fell on the Metroplex. The most to fall on a single day was 5.91 inches in October of 1959.
When a lot of rain falls in a short period of time, the ground can't absorb the water fast enough and we get a flood. Building restrictions and drainage systems prevent floods from destroying many homes and buildings, although in rare years the rain can overwhelm the planned systems and property damage can occur.
More often, the Dallas area gets flash floods which overrun low sections of roads. The water runs very fast over these sections and is often deeper than it looks. Always turn your car around and find a different route.
Severe weather includes thunderstorms, high winds, tornadoes, hail, and other natural events that can cause property damage or injury to human or animal life. Thunderstorms bring high winds and heavy rains many times during the year, but especially in the spring. According to NOAA, the Dallas area gets an average of seven thunderstorm wind days per year and seven hail days. Hail doesn't always occur with the high winds and thunderstorms, so those aren't necessarily the same seven days.
Tornadoes seem to be what concerns most people. While tornadoes can be deadly, their damage is usually limited to a small area. Most tornadoes last about ten minutes, but some can last much longer. They form fast and move unpredictably, so it's good to know about tornado safety.