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Weather   A summer close to ideal – in Ontario, that is Apart from one mid-summer heat wave, this year’s June-August weather was benign. But drought and forest fires ravaged the Canadian southwest and, globally, June and July were the second and third warmest on record by HENRY HENGEVELD Almost every one I talk to, whether farmer, landscaper, cottager or urbanite, seems to agree that this year’s weather for the June-August period was almost ideal. In sharp contrast to the summer of 2005, the number of very hot days was limited, air quality was great, and in most regions of Ontario the rain seem to come just when needed. Field crops, flower gardens and natural ecosystems, off to a good start after an early and pleasant spring season, appeared to flourish across most of the province. One notable exception to these benign conditions was the protracted mid-summer heat wave that began in mid-July and extended to early August. The sequence of days with temperatures above 30˚ C, warm nights and high humidity was more than just a bit uncomfortable. For outdoor workers, this discomfort peaked on Aug. 1, when temperatures across south and central regions reached levels in the mid- to high-30s.That day, whirring air conditioners pushed Ontario peak power consumption to almost 1,000 megawatts above any previous record. However, it was the preceding night that really stretched my bounds of tolerance. When minimum temperatures in the city failed to drop below 27˚ C that night, I almost conceded that we needed an air conditioner in our home. As the hot air was ushered out of the province the next day, the cold weather front brought with it some nasty thunderstorm activity. Eight relatively weak tornadoes were reported across Ontario that day, with most of the damage focused on cottage country north-east of Peterborough. However, once the heat wave had passed, the worst was over. During the rest of August, few days exceeded 30˚ C, and further severe weather activity was limited. Furthermore, throughout the summer, there were few cold days and lots of sun. Although the Great Lakes-St. Lawrence Basin was one degree warmer than normal for the season, it was only the 13th warmest since 1948. A far cry from the record-setting 2.2˚ C above normal we experienced last year! Likewise, average rainfall in the basin was a very modest one per cent above average.   While mid-August became somewhat dry, replenishing rains returned late in the month and in early September. Across Canada, the summer was the second warmest (after 1998) since national records began in 1948. However, added to the record-setting temperatures of both the past winter and spring, the first eight months of 2006 registered a record 2.5˚ C above normal. If the fall season also brings above normal temperatures, as predicted, the year is likely to eclipse the previous annual record set in 1998. On average, precipitation across the country was slightly below normal. The region hardest hit by drought was the Canadian southwest, where precipitation levels in some parts (particularly the southern B.C. mountains) fell to more than 40 per cent below normal. By early September, warm temperatures and the drought had generated severe forest fire hazards in southern B.C., and large uncontrolled fires were once again ravaging its border with Washington. Only parts of the Atlantic coast and the high Arctic experienced significantly above-normal precipitation. Globally, June and July were the second and third warmest on record, respectively -- this despite the lack of evidence of any El Niño effect. As in Canada, a major heat wave hit the United States particularly hard in the second half of July. Overseas, Europe was particularly warm, dry and sunny. During July, for example, the western European lowlands experienced temperatures some 5-6˚ C above average. In mid-July, the U.K. weather office also reported a new national high temperature record of 36.5˚ C, extremely unusual for that country’s maritime climate. However, despite early warnings of a high Atlantic hurricane activity season due to well-above-normal sea surface temperatures, by the end of August such events were still considerably below the norm. This left hurricane watchers somewhat puzzled and aware of their own inadequate understanding of related storm physics. And that’s the summer that was! BF Henry Hengeveld is Emeritus Associate, Science Assessment and Integration Branch/ACSD/MSC, Environment Canada.