DENVER -- In preparation for severe weather season, Denver and Lakewood tested their emergency sirens Wednesday.
The sirens are the cities' primary tornado alert system and a constant reminder that Colorado isn't immune to tornado danger.
They are battery-operated and solar-charged, and are much more reliable than the ones installed in the 1950s.
Severe weather isn't in the forecast Wednesday, so it was a good time to put the the equipment to the test.
In Lakewood, sirens were tested at 11 a.m., while Denver tested throughout the day.
Last week, small tornadoes were spotted in rural fields near Akron and Greeley.
"As we've already seen this summer, tornado season is already off to a violent start this year," Denver Director of Emergency Management Scott Field said. "It's always something we're concerned about. Denver is the front door step of tornado alley."
In 2012, a $2 million project brought new sirens to the city, improving reliability and coverage.
"The new ones are all on pole mounts so it allows us to be much more deliberate about where we place them," Field said. "It give us much better coverage. We now have coverage over 99 percent in the inhabitable part of the city."
With better technology in Denver, the sirens are sett off once a year in the spring so people can get used to hearing the noise. However, a much shorter test is still conducted on the second Wednesday of every month to ensure the sirens are operating year-round.