Shelter from the Storm: Weather-Induced Patterns in the use of Emergency Shelters

In Calgary, where winters are almost always long and temperatures can plummet below -30 C, it seems logical to assume that the highest rate of emergency-shelter use would occur on the coldest of days. On very cold days one might expect rough sleepers – those who for a variety of reasons sleep outdoors – to sleep in shelters. And yet, if social agencies were to operate on that assumption, and were to focus on significantly augmenting capacity on only bitterly cold days, the result could well be that not enough beds are made available when they are in fact needed. The number of people using emergency shelters follows a more or less regular pattern over the course of a week, a month and a year. Weekends, for example, find fewer people using emergency shelters. Seasonal influences are also important as are major holidays and the timing of income support cheques. An analysis of weather effects on emergency-shelter stays in the city of Calgary finds that the conditions that are most likely to move rough sleepers into shelter do not only occur during the depths of winter, but also during the so-called “shoulder seasons” of early spring and late fall. Weather related changes in the demand for shelter spaces is greatest when temperatures hover between 0 and -10 C, and when these temperatures are accompanied by wet snow or sleet. Those conditions can produce a temporary increase of 10 to 15 per cent over the average number of emergency-shelter users. The importance of realistically estimating shelter use should not be understated. Emergency shelters are so named for a reason: When an extraordinary number of homeless people face an urgent need for shelter, it is critical that shelter operators not find themselves caught unawares, and left either scrambling to secure additional capacity or, worse, forced to turn away those in need. Being adequately prepared for significant spikes in shelter usage requires an understanding of what causes shelter use to vary and this requires an appreciation of the role of weather conditions. Understanding that inclement weather in the spring and fall, when temperatures are only moderately below zero and wet snow or sleet is falling, drives large numbers of rough sleepers into shelters gives shelter operators the ability to better prepare for spikes in demand. Given the scarce resources available for shelter provisions, this improved preparation ensures enough beds are available at the times when they are most needed, and decreases the likelihood of potentially catastrophic outcomes.