North Texas is known for its ever-changing weather conditions. Violent thunderstorms may strike in an instant. Lightning, tornadoes, downbursts, hail, high winds and flooding are all dangerous by-products of thunderstorms that pose a significant threat to Frisco.
Watch Versus Warning
It is important to understand the difference between a severe weather watch versus a warning. Either can be issued by the National Weather Service (NWS) for a specific amount of time and designated area when atmospheric conditions are ripe for the development of a possible thunderstorm and/or tornado.
A watch means to watch the sky as conditions are right for possible development of severe weather. Keep an eye on developing weather and stay tuned to a local radio or television station in case conditions worsen.
A warning indicates a severe thunderstorm with dangerous conditions and/or tornado has been spotted or is indicated on the NWS radar. All those within the designated warning area should take cover immediately and remain there until the danger passes. The City of Frisco will activate the Outdoor Warning Sirens when severe weather, such as: hail of 1.25 inches or larger, winds of 70 mph or greater or a tornado threatens the community. If severe weather is approaching Frisco and the warning sirens are heard, seek shelter immediately and monitor TV and radio for further instructions.
What to Do in the Case of a Tornado
If a tornado warning is issued, go to a predetermined area where family members can safely gather and take shelter. Such an area could be a center hallway, bathroom, basement or closet on the lowest floor of the home. If in a multi-story building or a shopping mall, there may not be time to get to the lowest floor. In that case, go to the center of the building and find an area in a hallway far away from windows. If outside, hurry to the lowest floor of a sturdy building or lie flat in a ditch or low-lying area. If inside a mobile home, get out immediately and head to one of the above-named areas.
Turn on a radio or television and listen carefully to instructions. WBAP Radio 820 AM is the designated Emergency Alert System (EAS) station for our area. Frisco residents with cable should tune to:
- Channel 12 for Grande subscribers
- Channel 16 for Time-Warner subscribers
- Channel 37 for Verizon FIOS subscribers
- Channel 99 for AT&T U-verse subscribers
Stay indoors until the danger passes. Please do not call 911 or Frisco Fire Stations for information unless you are reporting a life-threatening situation or hazardous conditions.
Tornado Safety Actions
- Designate a safe shelter area if you live in a mobile or manufactured home.
- Get out of vehicles immediately and seek shelter in a building, if time permits, or move to a ditch or culvert away from the vehicle. Never try to outrun a tornado.
- Have disaster supplies on hand (flashlight, food / water, battery-operated radio, etc.) in an easily portable container, such as a backpack.
- Lie flat in the nearest depression, ditch or culvert if outdoors and unable to get to shelter. Cover your head with your arms to shield from flying debris.
- Monitor National Oceanic and Atmospheric Administration (NOAA) radio or local media (TV, radio, internet) for information.
- Move to a small interior room away from windows when a tornado warning is issued or a tornado is imminent.
- Take shelter in an interior hallway on a lower floor away from windows or glass when you're in a large building, such as a mall or auditorium.
Learn more: Ready.gov/tornadoes
The National Weather Service issues Severe Thunderstorm Warnings for a particular county, or portions of it, when dangerous winds and damaging hail are likely to exceed the thresholds known to cause significant damage to well-built structures or cause bodily harm to those outside.
Large hail is created by strong rising wind currents (updrafts) that carry water droplets into the upper regions of a thunderstorm where they freeze. Hail that is dime size or greater can produce dents in the tops of vehicles, damage roofs, break windows and cause significant bodily injury. Hailstones can form to softball size or larger and fall at speeds in excess of 100 miles per hour.
The largest recorded hailstone in the Dallas-Ft. Worth area, that was confirmed by the National Weather Service fell in Sanger, Tx (Denton county) on June 15, 2023. It's diameter was 5.9 inches and weighed .85 pounds. For comparison, the diameter of a softball is 4 inches.
Damaging winds are another dangerous ingredient that make up thunderstorms. Downbursts, also known as straight-line winds, are more prominent in thunderstorms. Downburst (straight-line) winds can produce widespread damage similar to that of a tornado. In fact, downburst winds have been measured in excess of 120 miles per hour or equivalent to an EF2 Tornado.
Thunderstorm Safety Actions
- Avoid driving into severe thunderstorms or consider delaying travel.
- Go to a small interior room on the lowest floor of your home, school, or business when severe thunderstorms threaten our community.
- Have disaster supplies on hand (flashlight, food/water, battery-operated radio, etc.)
- Monitor NOAA Weather Radio for Severe Thunderstorm Watches or Warnings.
- Move animals into shelter, and vehicles into garages to prevent damage, if time permits.
Learn more: Ready.gov/thunderstorms-lightning
Floods & Flash Flooding
Flood waters can rise quickly or slowly but typically develop over a period of days. Flash floods usually result from intense storms dropping large amounts of rain within a brief period.
Learn more: Ready.gov/floods
Flash Flooding Safety Actions
- Abandon vehicles stalled in rapidly rising flood water and move to higher ground immediately.
- Avoid walking through flooded areas. As little as 6 inches of swiftly moving water can sweep you off your feet.
- Never drive through a flooded area. If you come upon a flooded road, turn around and go another way.
- Watch for animals, especially snakes. Many animals lose their homes during flooding and may seek shelter in yours.