The Carvel station just west of Edmonton was listed as non-operational on a government website earlier in the day that carried the caption "No-Data."
Some media outlets that use radar images from the station for weather forecasts said the problem began Tuesday and that information was not available when a storm rolled across the region Wednesday afternoon.
"The weather radar had a failed part and a replacement has been shipped from Toronto," Danny Kingsberry, an Environment Canada spokesman, wrote in an email Thursday.
Accuweather, a U.S.-based company that uses Environment Canada data, said it was told the weather station was down for maintenance.
Carvel is part of Environment Canada's forecast and warning system that detects changes in the atmosphere and the development of impending severe weather such as tornadoes, hail and sudden downpours.
It was not immediately clear when the part failed, how often that happens or what safeguards are in place to ensure that such problems don't affect a weather station's ability to warn of severe weather.
Outages in the warning system have happened before.
On June 5, 2012, the Doppler radar station at Schuler in southeastern Alberta stopped transmitting data just as a tornado touched down near Taber and other twisters were reported near other communities.
No one was hurt, but the tornadoes damaged some buildings and trees.
Environment Canada said at the time that the weather radar was actually working, but a technical problem prevented the information from being transmitted.
The department's website notes there are an average of 43 tornadoes a year on the Prairies between June and August. On average, the Prairies are pummelled by about 130 severe hailstorms a year.
About two-thirds of Canada’s major documented hailstorms have occurred in Alberta.