Monday, July 28, 2008
Thursday, July 17, 2008
Sunday, July 13, 2008
Some peak wind gusts recorded yesterday included..
Oak Point Marine..... 94 km/h (east shore of Lake Manitoba)
Victoria Beach....... 91 km/h (east shore of Lake Winnipeg)
Brandon.............. 78 km/h
Dauphin.............. 78 km/h
Winnipeg............. 74 km/h
Gimli................ 69 km/h
Much better weather is in store today with sunny skies and lighter winds. After yesterday, we deserve it.
Friday, July 11, 2008
In Winnipeg, the heat wave started on July 5th and persisted for 2 weeks before easing on the 18th. From July 5-17, Winnipeg recorded 13 consecutive days above 30C, the longest such streak in Winnipeg history. During that stretch, 10 daily record highs were set or equalled which remain unbroken to this day.. an unparalleled feat in Winnipeg climate history. 9 of those days were 35C or more with 2 days hitting over 40C, including Winnipeg's all time mark of 42.2C on the 11th. The average daily high temperature during this period was an incredible 36.4C. Nighttime offered little relief from the heat with overnight lows rarely dropping below the 20C mark. In particular, the night of July 11-12th must have been unbearable for Winnipeg residents. After hitting an all time high of 42.2C on the 11th, the thermometer dropped to a "low" of only 28.3C the following morning, Winnipeg's warmest ever nighttime low. That means the temperature was above 30C most of the night. Imagine living in those conditions without air conditioning! In fact, the heat was too much for many residents, with at least 70 deaths recorded in southern MB due to the heat.
Even hotter temperatures occurred elsewhere in Southern Manitoba during the 1936 heat wave. Emerson MB near the US border recorded a phenomenal 7 days of 40C or more between July 6th and 17th, including a maximum of 44.4C on the 12th, Manitoba's hottest temperature on record. In fact, it was Canada's hottest ever temperature until Midale and Yellow Grass in southeast Saskatchewan hit 45.0C the following summer. During July 1936, Emerson registered 27 days of 30C or more, with an average high of 34.6C for the month, almost Arizona like. Between the 5th and the 13th, the town registered a remarkable 9 consecutive days of 100F or higher (37.8C)
Further south in North Dakota, Steele, ND hit an incredible 49.4C (121F) on July 6th, 1936.. a temperature value never equalled in that state since. By all accounts, the 1936 heat wave was an historic and unparalleled heat wave that has yet to be matched in weather record keeping. 6 years of drought had left the Prairies bone dry and crops withered, allowing maximum heating of the surface during the hot summer months. In the July 1936 event, a huge upper ridge must have developed over central North America, allowing extreme temperatures to reach well north into southern Canada. The upper pattern would have been stationary for at least 2 weeks, allowing the unrelenting heat to persist for days on end. Whatever the cause, the conditions that led to the 1936 heat wave have never come together again to the extent they did 72 years ago this week. So as you complain about this year's cool summer weather, try to think what residents of Manitoba had to endure during the granddaddy of all heat waves - July 1936.
Southern MB remains under a severe thunderstorm watch this afternoon as a low pressure system over eastern North Dakota draws a warm and humid airmass northward. Morning thunderstorm activity has pushed into the northern Interlake this afternoon, while the south gets a temporary reprieve from the severe weather. However, as the North Dakota low moves into southern MB later today, a flow of warm and humid air will be drawn over southeast MB while a cold front pushes in from the west. This will set the stage for additional severe thunderstorms to develop, especially over the Red River valley and southeast MB. Strong winds and large hail will be the main threat, however favourable wind shear profiles over southeast MB may give the threat of tornadoes with any supercell thunderstorms that develop.
As this low pressure system moves north into the Interlake tonight, it will deepen into an almost fall-like storm by Saturday morning with strong west to northwest winds developing on the backside of the low. Gale warnings have been issued for the MB lakes with west to northwest gales of 40 knots forecast for Saturday. This will likely generate large waves over the south basins of Lakes Winnipeg and Manitoba with possible shoreline erosion problems on eastern and southern shores. Temperatures will also be unseasonably cool Saturday with highs only in the mid teens along with occasional rain making it feel more like September than mid July. Not a good day for Grand Beach unless you like windsurfing!
Wednesday, July 09, 2008
Looks like another setup for possible severe thunderstorms to develop across Southern MB late Thursday into Thursday evening. A low pressure system and trough will be moving across southern SK Thursday moving to the SK/MB border by Thursday evening. A warm front extending east of this system will lie across the MB/ND border by evening which will be the focus for thunderstorm development. South of the warm front, warm and humid air will be advecting north from the Dakotas and will nose into Southern MB especially south and west of Winnipeg. Favourable low level wind shear and an increasing jet stream aloft will set the stage for supercell storms to develop across the Dakotas and southwest MB, with the potential for large hail and possible tornadoes. The limiting factor in this setup will be how much moisture can de drawn into this system in a short period of time, since dewpoints are quite low across the northern Plains today. As a result, the severe weather threat may be late Thursday before sufficient moisture can be drawn into this system. Stay tuned..
Thursday, July 03, 2008
Hot weather will be returning to southern MB over the next couple of days with highs approaching 30 degrees Friday, likely reaching the low 30s on Saturday. Saturday will also see increasing humidity levels as southerly winds tap more humid air to our south and advect it north. This will set the stage for possible strong to severe thunderstorms to develop by Saturday evening over the Red River valley as a weak cold front approaches from the west. Behind the cold front, more comfortable conditions will return for Sunday with seasonably warm and less humid conditions.