Good Question ‘Reply All’: Extreme Cold Edition
MINNEAPOLIS (WCCO) — Ila from Bemidji wanted the answer to a Good Question we get all the time: How do they keep from water in a water tower from freezing?
According to Brian Wagstrom, the public works director in Minnetonka, the water doesn’t freeze because 50-degree water from the ground is continually pumped up to the tower through an insulated riser.
He says there is sometimes a small build-up of ice, but they can prevent the tower from turning rock solid by controlling how much water flows in and out each day.
Angela from Alexandria fondly remembers the 69 below zero day back in ’96. She wanted to know: What would next week’s forecasted windchill of 40 to 60 below be back in the old system?
According to the WCCO-TV director of meteorology, the old wind chill measurements would be between 50 to 75 below zero. That’s for a forecast of minus 25 degrees with winds of 10 mph to 20 mph.
The National Weather Service changed the windchill index in 2001 to a more accurate measure of what windchill feels like on our skin.
In general, the old wind chill values will always sound colder than the new ones. Click here for a chart of how to determine the new and old windchills for all of those times people tell you it was a lot colder when they grew up.
Stephanie from Minneapolis asked: What happened to using sand on the roads? According to Mike Kennedy, director of snow operations for Minneapolis, many places still use sand for traction, especially when it’s too cold for salt to work.
But Kennedy says fewer municipalities are using sand because there’s a huge cost associated with cleaning it up in the spring and the sand can get stuck in the storm sewer system and eventually end up in our water.