Wednesday, October 10, 2012

City of Toronto Endured 21 Heat Alert Days in 2012

Photo credit: Chris Nagy

For anyone living or visiting the Canadian City of Toronto this summer, your time spent was more than likely accompanied by at least one Heat Alert. First used in 2001, the Heat Alert System was instituted as a way to warn citizens of days where higher than average heat-related injury or even fatality can occur.

From May 15th to September 30th, Toronto Public Health monitors the various meteorological conditions including temperatures, humidity, wind speed and cloud cover for conditions that compare to weather situations where higher levels of morality is possible. When potentially harmful weather conditions are detected, the Medical Office of Health for Toronto will issue a Heat Alert or a more severe Extreme Heat Alert warning the population as well as availing cooling centers for citizens of the major city. Summer of 2012 in the city of Toronto saw the second-highest recorded Heat Alert and Extreme Heat Alert days since the warning system was introduced.

For a total 21 times in 2012, the City of Toronto operated under the intervention of the Heat Alert System. Spanning from their first Heat Alert in May 28th, the Medical Officer of Heath declared the final Heat Alert on August 31st. Declaring a Heat Alert on 12 days in 2012 (two short of the highest amount of 14 issued in 2002), 9 days were also spent under an Extreme Heat Alert that required extra care during the summer. The Extreme Heat Alert count for 2012 is only half that of 2005 which is also the year where an all-time high of 26 overall Heat Alerts were issued over Toronto.

As typical with summer, the month of July provoked the most caution from the Medical Officer of Health. Dry conditions and a total of 12 days over where 30-degree Celsius temperatures reportedly baked the city through the course of the month led to a record-tying 11 days of overall Heat Alerts. In terms of other months of 2012, 6 Heat Alerts in the month of June and 3 in August is roughly average that  during monitored periods of other years. For the 5th time in 12 years under the Heat Alert System, May recorded a day of concern in 2012. However, 2012 ended a two-year streak of a Heat Alert in September.



Below is a set of historical charts compiled from data provided by the City of Toronto.


Days City of Toronto's Medical Officer of Health Declared
Heat Alert/ Type of Heat Alert

YEAR HEAT ALERT EXTREME HEAT ALERT TOTAL
2001 6 3 9
2002 14 2 16
2003 3 3 6
2004 2 0 2
2005 8 18 26
2006 9 8 17
2007 10 5 15
2008 3 6 9
2009 1 2 3
2010 5 11 16
2011 7 5 12
2012 12 9 21



Heat Alert Occurrences According to Months of Year

YEAR May June July August September
2001 0 3 2 4 0
2002 0 0 11 5 0
2003 0 4 2 0 0
2004 0 0 2 0 0
2005 0 13 9 4 0
2006 3 3 9 2 0
2007 2 6 3 4 0
2008 0 2 6 1 0
2009 0 2 0 1 0
2010 6 0 5 3 2
2011 1 1 8 1 1
2012 1 6 11 3 0