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Thunderstorms and Lightning

Thunderstorms can develop in Duval County at any time, but they are most frequent in late spring through early fall. All thunderstorms produce lightning. According to the Centers for Disease Control, Florida is considered the “lightning capital” of the country, with more than 2,000 lightning-related injuries occurring within the state over the last 50 years. If you hear thunder, lightning is close enough to strike. 
Severe Thunderstorm Risk Categories
Marginal Risk (MRGL)
Isolated severe thunderstorms possible
Limited in duration and/or coverage and/or intensity Wind to 40-60 mph, hail up to 1”, and low tornado risk
Slight Risk (SLGT)
Scattered severe storms possible
Short-lived or not widespread, isolated intense storms One or two tornados Reports of strong winds and wind damage Hail -1”, isolated 2”
Enhanced Risk (ENH)
Numerous severe storms possible
More persistent and/or widespread, a few intense A few tornadoes Several wind damage reports. Damaging hail 1”-2”
Moderate Risk (MDT)
Widespread severe storms likely
Long-lived, widespread and intense Strong tornadoes Widespread wind damage Destructive hail, 2” or greater
High Risk (High)
Widespread severe storms expected
Long-lived, very widespread, and particularly intense Tornado outbreak Derecho (widespread, long-lived wind storms)
During A Thunderstorm
  • Go inside or seek shelter immediately
  • Avoid objects that conduct electricity
  • Get as far away from water as possible
  • Avoid open areas and high ground
City of Jacksonville Lightning Warning Systems
The City of Jacksonville maintains lightning warning systems at 5 public parks:
  • Ringhaver Park
  • Losco Regional Park
  • Earl Johnson Park
  • Chuck Rogers Park
  • Patton Park
The sensor for these alarms continuously monitors the atmosphere’s electrostatic energy as far away as 15 miles and evaluates the potential for lightning within an area approximately 2 miles in radius. When the system determines a hazardous condition, the air-horns sound off to provide necessary alerts.