Saturday, 7 January 2012

Top 10 Weather Events of 2011 - #2

#2 Summery October    

     The first third of October was very warm, very dry, and at times very windy. An upper ridge of high pressure centered over central North America was the culprit. Every day from Oct 1 to 12 saw above normal temperatures, including 8 which saw temperatures over 20 C. Although, it was particularly hot from Oct 4 to 7. Manitobans welcomed the return of mid-summer temperatures, although those warm temperatures came with some real consequences. The following is a summary of the extreme and odd weather we experienced Oct 4 to 7.

     Temperatures from Oct 4 to 7 were 10 to 20 C above normal. Forget about the normal high of 14 C, and normal low of 2 C. Highs were in the high twenties to low thirties, and lows in the mid to high teens.
     October 5 featured the peak of the heat. A very strong south wind pumped in 925 mb temperatures of 25 C (see 925 mb plot). That translated into daytime highs in the low thirties throughout southern Manitoba. 925 mb temperatures of 25 C are very extreme for October. In comparison, that would translate into temperatures in the high thirties in the summer with plentiful sunshine. By noon, it was already 26 C in WPG, and by afternoon, the temperature peaked at 31.1 C. It was the hottest October day in the city’s history, beating the previous hottest October day of 30.5 C on Oct 1, 1992. Much of southern Manitoba reached the 30 degree mark, and broke records. Many took advantage of this late summer treat to go swimming at beaches such as the one at Birds Hill Park. It would have been quite surreal to be sitting at the beach in a bathing suit, or splashing in the water in October.
     Winnipeg has hit 30 C in October only 3 times since 1872, proving how rare this October day was.  Although, parts of the western RRV have hit 30 C many times in October, and have hit 30 C as late as October 16. Here are some selected highs attained October 5. Official records are in bold:
Oct 5 High
Old Record
Records Began
24.4 (1943)
29.4 (1943)
28.3 (1943)

29.4 (1943)

     Comparatively, Mexico City reached a high of 26.2 C that same day.
     At night, temperatures stayed very warm thanks to a strong southerly wind. In WPG, it was still 24.1 C at 11 pm. In addition to the record high on Oct 5, a record high minimum of 16.1 C was also broken. A low of 16.7 C on Oct 6 also broke a high minimum record, and was the 2nd warmest high minimum in October history. The warmest minimum was 17.2 C in 1897, which we almost broke on Oct 7. The morning low was a jaw-dropping 19.1 C, but a cold front in the afternoon cooled temperatures enough by evening that we did not break it.

     That same cold front triggered thunderstorms throughout the south in the afternoon. Lots of lightning, heavy downpours and pea to marble sized hail were reported in the Interlake. As if it didn’t feel like summer enough already!
Photo is from a Theweathernetwork viewer
     Behind the front, winds picked up drastically. Winds gusting over 90 km/h caused severe damage. To give an idea of the strength of the winds, a camper trailer being towed by a truck on Hwy 59 got picked up by the winds and landed on the truck towing it, which then veered into oncoming traffic. Luckily, there were no injuries. In the city, trees were uprooted, some landing on power lines, poles and transformers. Numerous traffic lights flickered, with power outages throughout the area. Manitoba Hydro had to call-in extra emergency-repair crews to fix all the outages that were occurring. Thousands were without power at one point. Some trees landed on homes, garages, and fences, keeping tree services very busy the next day.

     And finally, the warmth, strong winds, very low humidity and very dry soil conditions all combined to create ideal conditions for fires. Environment Canada does not issue warnings for fire weather, although, the fire weather watches and red flag warnings in North Dakota and Minnesota could have just as easily been extended into southern Manitoba. The fire rating was pushed to extreme, the second time this year. Fire and burn bans were issued in some areas to avoid man-made fires.
     Several fires did in fact pop up throughout southern Manitoba during that week. Many were small fires, although there were also a number of large fires as well, such as in:
·         RM of Stuartburn – RM declared a state of emergency. 60 people evacuated in the town of Stuartburn, 90 km south of WPG. Several firefighters and 4 water bombers fought at least 4 serious fires, saving all property. Hwy 59 & 201 were closed as a result of fire and smoke. 100    were also evacuated near Caliento, Lonesand and Zhoda as fires crept closer to those communities.
Riding Mountain fire
·         Riding Mountain National Park – Firefighters from Saskatchewan and BC were flown in to help battle the flames. The fire began where a controlled burn had previously been extinguished in late September. All roads, highways and trails east of Hwy 10 were closed. 2,000 hectares of land burnt, in an area 12 km long from south to north.
·         Bissett – Firefighters from Ontario and BC were flown in to help battle an 18,000 hectare fire about 10 km north of the town of Bissett. 8 helicopters, 4 water bombers, and around 100 ground crew fought the flames. The fire covered an area 40 km long and 6 km wide. Hwy 304 was closed due to heavy smoke and flames. This large fire was ignited by lightning.
·         Sandilands/Woodridge – 400 were evacuated as flames approached the communities. 20,000 hectares of land was burned. Smoke from the fire also forced an additional 350 people out of their homes in Marchand before wind changed direction.
·         Peguis First Nation – 1 500 hectares of land was burned.
     Several other small fires sprung up as well, such as near Lac du Bonnet, Bird Lake and La Broquerie. Cooler temperatures, higher humidity and lighter winds improved the situation immensely by Oct 9 and beyond. This many fires in October are definitely fairly unusual. All in all, it was an extremely unusual week of summer heat, vicious winds, grass fires and thunderstorms. This kind of weather in October may never be repeated in a lifetime, and will be remembered for years to come.
CBC Manitoba, Fires rage across Manitoba, force evacuations. (Oct 7, 2011). Access 12/22/11 from < >
CBC Manitoba, Fire creeps toward Manitoba villages. (Oct 8, 2011). Access 12/22/11 from <>
CTV Winnipeg, Controlled burn turns into wildfire in Riding Mountain National Park. (Oct 7, 2011). Access 12/22/11 from < >
CTV Winnipeg, Weather cooperating with fire fight in southeastern Manitoba. (Oct 9, 2011). Access 12/22/11 from<>
Winnipeg Free Press, Firefighters battle blazes across the province. (Oct 7, 2011). Access 12/22/11 from < >
Winnipeg Free Press, Wind storm keeps hydro, city and firefighters busy. (Oct 7, 2011). Access 12/22/11 from < >

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