Chinooks are warming winds blowing west off the ocean into Alberta, Canada, and the U.S. Pacific Northwest. These can increase temperatures from below −20 °C (−4 °F) to as high as 10–20 °C (50–68 °F) for a few hours or days, before they fall back to their base levels again. The Alberta ’hot spot’ is over Lethbridge, 200 kilometres south of Calgary. Let us learn a bit more about what makes chinook winds tick first.
How Chinook Winds Come and Go
Chinook winds develop when moist warm air arrives from the Pacific Ocean and meets the Rocky Mountains. As it ascends, the warm air cools, releasing rain and snow on the peaks.
The now dry air warms as it descends to lower eastern regions. If the wind direction shifts to the west, or southwest the rate begins to accelerate. In Southwest Alberta, chinook winds can reach hurricane force. In 1962, one gusted to 171 km/h (106 mph) at Lethbridge.
These conditions play havoc with loose eavestrough gutter systems and sagging soffits, especially as ‘snow-eating’ chinook winds can vaporise a foot of snow in a few hours before it has a chance to melt.
When is Chinook Season in Alberta?
Conditions are right for chinooks in winter, when blankets of high snow cool the maritime air. Lethbridge gets 30 – 35 chinook days a year, while Calgary is not far behind.
The hot winds appear to be currently on the increase. This could be due to global warming. As siding, soffit and gutter specialists, we experience chinook winds as rapid snow melts on roofs, and masses of water swirling in strong gusts.
When is the Right Time to Take Remedial Action?
As soon as snow finally melts in spring, and we can see the result, we find ourselves exceptionally busy repairing chinook damage. We take advantage of the calmer period during April and May before heavy rains return in June. Please consider booking a gutter inspection early, so we set time aside to attend to your needs.
Please call Valiant Exteriors on 403 829 1661, or email us anytime for free advice on your eavestrough gutter systems. We would be delighted to quote for any remedial work that transpires, and are pleased to be of assistance.