Summer has decided to hang on and not leave us quite yet, bringing record-breaking heat to much of the Canadian Prairies. A large upper ridge build into the region on Tuesday and Wednesday, pushing the jet stream all the way up to the 60th parallel which has allowed a hot, dry southwest flow to remain in place over Alberta, Saskatchewan and Manitoba for days on end. Records have fallen left in right, with some of the highest daily quantities of records being broken at once over the last two days.
How long will this heat stay with us? How hot is it going to get? Click through to read more!
On Wednesday, September 7th, 22 record highs were broken across Alberta, Saskatchewan and Manitoba:
Daily Record Temperatures set September 7, 2011
Of note on this day:
- North Battleford broke a daily record high temperature that was set in 1893, a record 118 years old.
- Many record highs were broken by at least 2 or 3°C, and some by nearly 10°C.
On Thursday, September 8th, 22 record highs were broken across Alberta, Saskatchewan and Manitoba:
Daily Record Temperatures set September 8, 2011
And today, September 9th, 2011, 18 records were broken:
Daily Record Temperatures set September 9, 2011
This record-setting heat is all thanks to an impressive upper ridge that has built into the Prairies. This is a feature located high in the atmosphere that causes a large area of air to subside (move downwards). Combined with the fact that they build up from the south, they bring a lot of warm air along with themselves, and often result in a large area seeing sunny skies, light winds and hot, dry weather.
The upper ridge will remain in our area for the next couple days, with daytime highs remaining in the low 30°C range. Winnipeg has an honest shot at breaking our daily record high temperature tomorrow which sits at 32.4°C. Things will abruptly change next week however. On Monday a low pressure system will pass by to our north and drag a cold front down across the province. Through the following days, a large ridge of high pressure will build in from the northwest, bringing significantly cooler temperatures than the past week:
GFS Surface Temperatures Valid 06Z Thursday 15 September
Currently it looks like next Wednesday and Thursday will be the coldest of the days, with highs struggling to get as high as 15°C. While the last week has been a beautiful late-season blast of summer, fall is set to make an aggressive entrance early next week.
In a new post over at Rob’s Blog, Rob describes exactly how dry it has been this summer in Winnipeg. I recommend you head over and read it, but the highlights are:
- This summer the CYWG airport site recorded 93.0mm of rain from June to August.
- This value is over 140mm below average
- This year was the driest summer since 2006, when only 91.5mm of rain was recorded.
- Southwest Manitoba and the Southern RRV experienced near-normal amounts of rain while the Northern RRV and Eastern MB experienced the dry conditions this summer.
- This summer was the 5th driest summer on record.
Be sure to head over to Rob’s Blog to see the whole post and some more details on this summer compared to climatology. All in all, if you enjoy the sun, this summer in Winnipeg has been the summer for you!
The hot and dry weather came to an abrupt end early Thursday morning when Winnipeg received ~20mm of rain as a large complex of thunderstorms rolled through Southern Manitoba, giving large amounts of rain and winds as high as 110km/h over portions of extreme Southern MB. After a day of sun with much cooler temperatures, Winnipeg is set to likely receive another round of showers tonight. Read on to find out what’s in store!
Water Vapor (7µm) Image of Canada from 2:15PM CDT. L – Low; Blue Line – Cold Front; Red Line – Warm Front; Green Arrows – Expected Track of Low
A moderately strong upper low is tracking southeastwards across the Prairies today and will slump to the International Border near Melita by late this evening and then slide east along the border, crossing over the RRV overnight. A frontal wave associated with this system will mirror its parent’s motion and slide along the same track ahead of the system, arriving at the western edge of the RRV by early-to-mid evening.
6 Hour QPF from GEM-REG 12Z Model Run valid at 06Z 03 Sept. 2011 (1AM CDT)
Showers and isolated thunderstorms will develop along the warm front early this evening, pushing into the RRV around midnight. The rain will push across the RRV and through Winnipeg overnight. Most of the RRV will see only 2-4mm of rain, and there is no risk of severe thunderstorms. Perhaps a bigger story with this system is rainfall totals in areas north of the the low track.
24 Hour Total QPF from GEM-REG 12Z Model Run valid at 12Z 03 Sept. 2011
The above picture shows the total amount of rain that is expected to fall from Friday 7 A.M. CDT to Saturday 7 A.M. CDT. Over 40mm of rain are expected to fall across portions of Eastern Saskatchewan, across the Parkland areas of Manitoba including Dapuhin and Minneodsa, through the Interlake and into Northwestern Ontario.
For Saturday, Winnipeg and the rest of the RRV will see the chance of showers as the cold front pushes through in the morning. By early afternoon things will begin to stabilize with the passage of the front, and most of the RRV will see winds of 30-40km/h behind the cold front with gusts up to 60km/h.
Chart of 500mb Heights and Temperatures valid for the evening of Wed. Sept. 7
Things look calm in the long-term, as after this system the upper ridge begins to redevelop aloft. It will continue to intensify through the next week, bringing sunny skies and the return of warmer weather. We should see relatively light winds most of next week with daytime highs in the mid-20’s. Summer isn’t over yet!
An extremely warm air mass, combined with brisk westerly winds, brought record heat to much of southern Manitoba. Winnipeg officially reached 37.0C today, breaking the old record of 36.7C set in 1952 and marking the warmest day the city has seen since June 17, 1995 when the mercury soared to 37.8C.
The warm weather spread into Southern Manitoba ahead of a cold front sweeping cooler air into the province by Tuesday evening. A westerly, downslope flow coupled with extremely warm air at 850 mb pushed the mercury to record-breaking levels in many areas across Southern and Central Manitoba, including:
|Location||New Record||Old Record|
|Fisher Branch||34.2°||31.0° (1990)||1977|
|Island Lake||29.1°||27.8° (1976)||1971|
One thing that was very interesting, though, was that the International Airport in Winnipeg was actually one of the cold spots in the city. Various personal weather stations reported even higher temperatures:
|Birds Hill Park||38.0°|
|East St. Paul||37.0°|
Fortunately, a cold front passing through this evening will usher in cooler weather and stronger winds. An intensifying surface pressure gradient on the back-side of the cold front will bring strong winds into Winnipeg tomorrow with sustained winds expected to reach 50km/h with the potential for gusts as high as 80km/h. Temperatures will be about 13-15 degrees cooler than today, with highs of 23-25° expected for much of Southern Manitoba.
12Z Aug 23 GEM-GLB Temperature valid 00Z Fri Aug 26
However, after just one cooler day, warmer weather is expected to return to Southern Manitoba. By Thursday afternoon, temperatures should push back up towards the 30° mark with a southerly flow that redevelops through the day. Late Thursday evening a cold front will pass across the RRV, bringing us back into daytime highs of 22-25° for the weekend. Currently, no precipitation is expected with this front, but I’ll keep an eye on it through the week.