Weld County leads the nation in tornado activity, with at least 292 reported since 1950. While many of the tornadoes that occur are small in size and leave little damage, some are significant, such as the Windsor Tornado in 2008 (EF-3) and the EF-2 tornado near Firestone in 2021.

Tornado tips

• Pay attention to the skies and monitor weather reports to know when weather changes and what actions to take.

• Become familiar with severe weather terminology commonly used in weather reports.
  •  Advisory – Weather, such as a winter weather advisory, that may be a slight disturbance or nuisance, but not expected to be life threatening or warrant a watch or warning. Be aware that severe weather may occur!
  •  Watch – Weather conditions are right for a specific weather event — thunderstorm, tornado, blizzard, etc. However, a watch only means specific weather is possible in a given area, not that it will definitely occur.
  •  Warning – A weather event is already happening or about to happen in a given area. Take action!
   

Thunderstorms are classified as severe if they produce hail, tornadoes, or windspeeds greater than 58 miles per hour. Lightning often accompanies thunderstorms and in 2023, Colorado ranked 18th nationwide in lightning events (or strikes) with 4,374,814 events recorded. In terms of lightning density — the number of events per square kilometer — Colorado ranked 23rd with 16.2. according to the 2023 Annual Lightning Report from Vaisala XWeather and the National Lightning Detection Network. Maps in the report show Weld County's lightning density increased an estimated 25% in 2023 from its average between 2016 and 2022.

View the report.

Thunder and lightning tips

• As thunderstorms can often be accompanied by strong wind,  before a storm arrives, secure outdoor furniture and take light objects inside to avoid damage.

• During thunderstorm, consider unplugging electrical equipment to avoid damage from a power surge, and stay away from windows, doors and off of porches. If in a car, during a thunderstorm, stay there. The rubber from the tires can serve as protection from lighting strikes — just avoid touching the medal frame of the car.

• Be aware of the 30/30 rule: If you cannot count to 30 between seeing lightning and hearing thunder, it's a good idea to go indoors and stay there for 30 minutes after hearing the last thunder clasp.

Flooding is another element that can impact residents in the spring and summer months. One of the more significant floods impacting Weld County occurred in 2013. Over the course of two weeks, floodwaters closed more than 100 county roads, with residents from every region of Weld County (Greeley/Evans, north, southeast, and southwest) reporting property damage. Total statewide residential property damage in 2013 was estimated at $900 million, according to a report from Reuters.

Flooding tips

• An emergency preparedness plan and disaster supply kit can be beneficial for any emergency situation, and a flood is no exception. Consider creating an emergency preparedness plan, detailing evacuation information for your home and how to stay in contact with family if separated. It's a good idea to have disaster supply kits ready, full of items to keep everyone safe for 72 hours following an emergency. More information on creating an emergency preparedness plan and disaster supply kit can be found in tip No. 2 and No. 6 of our emergency preparedness tips. 

• During a flash flood, seek higher ground immediately. Do not wait for instructions to move.

• Never drive through standing water. 

A 2024 report by Roof Gnome shows Colorado remains one of the most hail-prone states in the U.S. with three counties ranking in the top-10 as being most at risk for hail damage. Weld County ranked 250th out of 604 counties most at risk of hail damage, and the Federal Emergency Management Agency (FEMA) National Risk Index Study showed the county's risk index as relatively moderate. Although not one of the nation's top hail- producing counties, Weld County experiences plenty of hail throughout the spring and summer months, with stones ranging greatly in size.

See the Roof Gnome report. See the FEMA National Risk Index Study.

Hail tips

• During a hailstorm, move inside and stay inside. Stay away from windows, and move into the basement or an interior room.

• If on the road during a hailstorm, slow down or stop as roads can become slippery. If pulled over, turn your back to windows or cover yourself with a blanket to protect yourself from broken glass. 

Open grass fires — also known as prairie fires or wildfires — can start in overly dry conditions or as agricultural burns that grow rapidly and are too big to control. Lightning strikes are also a big cause of open grass fires in Colorado.

Grass fire tips

• Always monitor weather and drought conditions. Don't burn when it's exceptionally dry or windy.

• While agricultural burning in Weld County — typically the burning of water conveyance ditches and/or fields to prepare land for the planting of commercial crops — doesn't require a permit,  other types may require a permit. Visit the Weld County Department of Public Health and Environment for more information.

• If you notice what could be an open grass fire, Call 9-1-1 to report the fire; don’t assume someone else has called.

• If time allows, close windows, vents, and doors. Shut off gas, or turn off propane at the tank. Open the fireplace damper and close the fireplace screen. Bring any patio furniture inside.

•  If you are concerned about a wildfire in your area, leave and go to a safe place outside of the area. Do not wait to be told by officials to evacuate.

• Tune in to local media sources for more information.