Monday, August 18, 2008

Winnipeg finally hits 30 degree mark - latest date on record

The temperature at Winnipeg airport hit 30.2C on Saturday August 16th, the first official 30 degree day of the summer at Winnipeg's official weather reporting site.  This marks the latest date that Winnipeg has reached the 30 degree mark since records began in the city in 1872.  The previous latest date for hitting 30C was July 24th back in 1927 and in 1882.  Thus, this year was over 3 weeks later than the previous latest date.   The average date for hitting 30C is around June 4th based on Winnipeg climate data since 1872.

Note that Winnipeg airport observations began in 1938.  Before that, weather readings were taken at St John's College in St Boniface from 1872-1938. 



2008...AUG 16…. 30.2C…..138   
1882…JUL  24…. 30.0C…..115   
1927…JUL 24….. 32.2C…..115
1920…JUL 19….. 31.7C…..110
1967….JUL 15…. 30.0C…..106



  1. At least we did finally reach 30!

    Looks like a potential severe weather outbreak later this week. It could be similar to the late July one, which ended up sweeping through all of Southern Manitoba. There will actually be some shear on Thursday (day of potential outbreak), with 850mb winds reaching 40 knots over the RRV.

  2. The WRF is now predicting a fairly large Wednesday/Thursday severe weather outbreak in Southern Manitoba. On Wednesday is should be limited to West-Central Manitoba (i.e. Dauphin/Swan River/Flin Flon) due to strong capping. By Thursday most of Southern Manitoba will be at risk, with 2000 to 3000J/kg SBCAPE and a strong 40 knots Low Level Jet at 850mb. There may be an MCS as a result of this, which could hammer South-Eastern Manitoba, given the 60 knot winds at 850mb by 06Z on Friday!

    On another note August may finally break our below-normal spree. The current average high at my station is 26.2, which is usually within a couple tenths of a degree to the Winnipeg Airport.

  3. Crazy hot in SK today getting to 38 in a few places - even Saskatoon got to 37! I imagine things here won't get as hot because there's more moisture in the air... sure is making for a fantastic summer evening :)

  4. It is going to be a humid couple of days. Today the dewpoint went way above what was forecast (forecast was for a 16 to 18C DP). It seems like all summer the DP has been 1 to 3 degrees higher than the popular models have indicated. I wouldn't be surprised to see a humidex advisory out either tomorrow or Thursday for high humidity. If the DP even reaches todays value again tomorrow, we could easily see a humidex value of 40 or 41 degrees, and by Thursday the humidex could reach the 42 to 45 range (at the very most).

    Still looking good for some severe weather on Thursday, these high dewpoints will only help the situation. Rob...are dewpoints still being enhanced by evapotranspiration off the crops, or is this purely transported moisture?

  5. I suspect there's still some evapotranspiration going on, mainly due to the delayed growing season this year and this past week's heat.. corn for example, a major moisture source, is just maturing now in many areas which is later than usual. Dewpoints south of us in ND were only in the midteens (e.g. Fargo) so I suspect the higher dewpoints we saw today were locally enhanced.

    Even so, I was surprised how humid it got this afternoon after such a cool morning (down to 11C) Those southerly winds will be even stronger tomorrow (gusting 60 up the valley) which will help ventilate those hot and humid conditions somewhat. As Scott alluded to, looks like we could see some severe weather by Thursday evening as cold front approaches SW MB. Looks like we're finally getting our July weather!

  6. Looks like today and tomorrow is going to be hot and humid!
    I suspect that tomorrow night is going to be a real stormy one with storms moving in the Winnipeg area around midnight!

  7. Tomorrow's weather setup reminds me a lot of the one in late July. Fairly high SBCAPE values in South-Western Manitoba in the evening create numerous strong thunderstorms. Those storms then form into a line which sweeps through the rest of the province overnight.

    One big plus is the strong Low Level Jet. Winds at 850mb will be around 40knots in the evening, then will increase to 60knots overnight. Mid-level winds also increase, leading to a strong line of storms/MCS.

    The only issue I see as a problem is strong capping in the evening. If the front can breach that there shouldn't be any issues.