Environment Canada

Environment Canada

August 01, 2006 13:55 ET

Environment Canada: Ontario Weather Review

July 2006

TORONTO, ONTARIO--(CCNMatthews - Aug. 1, 2006) - Call July a month of extremes. It was hot throughout Ontario, but in some locations it was hot and wet and in others it was hot and dry.

The province continues to have above-normal temperatures, in some cases more than two degrees above normal. This month was very reminiscent of last July, when air conditioners were running nonstop throughout the month. In the northern and northwest parts of Ontario, this month was the warmest since 2002.

The rain? It was hit and miss. Dry conditions were felt in locations across the province, with sparse rainfall reports. In some cases, however, the rains fell very quickly and in large quantities. Single-day rainfall amounts exceeding 50 millimetres were reported in a number of areas: Wawa on July 1, Kitchener on July 12, North Bay on July 26 and Thunder Bay on July 31, to name four of Environment Canada's major reporting sites. And at one of the volunteer sites, Sprucedale (30 kilometres northwest of Huntsville), 90 millimetres was reported on July 25. The sporadic severe weather brought the monthly totals well above normal, but without these extreme single-day events these areas too would have had below-normal rainfall for the month.

Severe Weather

July was a very active month for severe weather, with reports ranging from funnel clouds and tornadoes to widespread damaging wind gusts and heavy rainfalls. The activity began early in the month with damaging storms July 3 and 4 in portions of Southern and Eastern Ontario. This culminated with the confirmation of a tornado in the Cobden area of Eastern Ontario. The severe weather picked up again July 10 over a good portion of Southern Ontario with reports of heavy rain, small hail and numerous funnel cloud sightings.

However, the day which resulted in the most reports of damaging weather was July 17. A cold front moving down from Northwestern Ontario kicked off three distinct bands of severe weather. Beginning in the morning north of Lake Superior, in the Hornepayne area, a large complex of thunderstorms created damaging winds, hail and heavy rain as it tracked eastwards. Before this area exited Ontario, it created a damage path near Kirkland Lake and eastwards towards Larder Lake. By late afternoon, another area of thunderstorms became organized to the west of Manitoulin Island. Between approximately 4 p.m. and 7 p.m. this area of thunderstorms raced eastwards, generating sporadic strong wind gusts called microbursts. The speed of some of these wind gusts was between 120 and 160 kilometres per hour and damage was reported in a large number of localities from Manitoulin Island to south of Sudbury, through North Bay and into the Mattawa and Deep River areas. The area continued eastward into Quebec and the resulting path of intermittent damage was more than 600 kilometres long. Finally, during the evening hours a series of powerful thunderstorms pounded portions of Southern Ontario, with damage occurring in many localities. Most notably, two tornadoes touched down in the Newmarket area and extensive tree damage occurred in and around Peterborough, due to strong wind gusts.

Hot, humid air lingered over Southern Ontario at the end of the month and acted as the fuel to drive intense thunderstorms in that part of the province.

With the Cobden area tornado, as well as the two tornadoes in the Newmarket area and the recently confirmed June 21 tornado in the Kakabeka Falls area to the west of Thunder Bay, the 2006 Ontario tornado tally now stands at eight. Ontario normally is hit by 14 tornadoes during the summer severe weather season, which runs from late April to early October.



Unusual mean temperature readings:

------------------ ----------- --------- ------------ ---------------
Location Mean Temp Normal Difference Warmest Since
------------------ ----------- --------- ------------ ---------------
Sault Ste Marie 20.3 17.6 2.7 1983
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Toronto Pearson 23.4 20.8 2.6 2005
------------------ ----------- --------- ------------ ---------------
Kenora 21.9 19.5 2.4 2002
------------------ ----------- --------- ------------ ---------------
Wawa 17.2 14.8 2.4 2005
------------------ ----------- --------- ------------ ---------------
Dryden 21.0 18.8 2.2 2002
------------------ ----------- --------- ------------ ---------------
Muskoka 20.6 18.5 2.1 1955
------------------ ----------- --------- ------------ ---------------
Wiarton 20.7 18.6 2.1 1999
------------------ ----------- --------- ------------ ---------------
Sioux Lookout 20.6 18.6 2.0 2002
------------------ ----------- --------- ------------ ---------------

Unusual precipitation readings (in millimetres):

------------------ --------------------- ------------ --------------
Location Precipitation Normal Difference Driest Since
------------------ ------------- ------- ------------ --------------
Geraldton 51.4 111. -60.3 2005
--------------- -- ------------- ------- -------- -- --------------
Kenora 38.6 95.3 -56.7 1985
--------------- -- ------------- -------------------- --------------
Dryde 46.5 98.8 -52.3 2005
------------------ ------------- -------------- ----- --------------
Moosonee 74.2 101.3 -27.1 2004
---------------- - ------------- ------- ------------ --------------

------------------ ------------- ------- ------------ --------------
Location Precipitation Normal Difference Wettest Since
------------------ ------------- ------- ------------ --------------
Waterloo
Wellington 182.5 91.8 90.7 2005
------------------ ------------- ------- ------------ --------------
London 151.4 82.2 69.2 1992
------------------ ------------- ------- ------------ --------------
Windsor 147.2 81.8 65.4 1996
------------------ ------------- ------- ------------ --------------
Hamilton 149.2 86.5 62.7 1992
------------------ ------------- ------- ------------ --------------
Wawa 156.6 101.5 55.1 1990
------------------ ------------- ------- ------------ --------------
Earlton 134.5 79.7 54.8 1985
------------------ ------------- ------- ------------ --------------
Timmins 144.8 91.5 53.3 1990
------------------ ------------- ------- ------------ --------------
Toronto City 120.8 67.5 53.3 1996
------------------ ------------- ------- ------------ --------------
Pickle Lake 151.1 105.4 45.7 1999
------------------ ------------- ------- ------------ --------------
Sarnia 116.5 74.1 42.4 1997
------------------ ------------- ------- ------------ --------------
Kapuskasing 139.6 100.5 39.1 1997
------------------ ------------- ------- ------------ --------------
Thunder Bay 124.5 89.0 35.5 1997
------------------ ------------- ------- ------------ --------------
North Bay 133.0 100.1 32.9 2004
------------------ ------------- ------- ------------ --------------
Toronto Pearson 105.2 74.4 30.8 2004
------------------ ------------- ------- ------------ --------------


(Egalement offert en francais)

Contact Information

  • Environment Canada, Ontario Region
    Jack Saunders
    Communications Advisor/Media Relations
    (416) 739-4785
    www.ec.gc.ca