Tuesday, September 21, 2010

24C by Sunday? Could it be?

Long range models continue to indicate an upcoming change this weekend in the below normal weather pattern that has plagued the Prairies most of September. A large upper ridge is forecast to build over western North America by the weekend that will send a surge of warm air across Alberta and Saskatchewan beginning Saturday. Low pressure crossing the northern Prairies will push this warmth eastward over southern Manitoba on Sunday with temperatures expected to climb into the low to mid 20s.. potentially the warmest day of the month so far that has seen only 2 days reach the 20C mark in Winnipeg, with a maximum of only 22C on the 1st. Current forecasts suggest 24C temperatures continuing Monday in Winnipeg however, model guidance is indicating a brief cooldown Monday and Tuesday before another surge of warm air moves in for the middle and end of next week. All in all, it looks like we may finally be seeing some above normal temperatures to end what has been a generally cool September.


  1. Looks like some area's of southern Manitoba is getting a good soaking today!

    Nowhere near as bad as areas in Minneasota that could see 3-4 inches of rain!

  2. Sneaky rain event today and tonight. Models have gone from showing 0mm of precipitation in Winnipeg yesterday to around 15mm today. Looks like even heavier amounts near the border, with most models indicating at least 30mm.

  3. Is it true that these rains are the result of the remnant moisture of Hurricane Karl that hit Mexico last week?

    I ask because I heard that the flooding rains associated with the same low pressure system in the Midwest US were the result of Karl's remnant moisture surging northwards, being pulled northwards by the low pressure centre.

  4. With some more rain today it looks like Rob's weather station will go over 100 mm!
    That would put us almost DOUBLE the average rain for Septmeber!

    Another water-logged month!

  5. Anon..

    Yes, this system is tapping some tropical moisture from the remnants of Karl.. very heavy rains past 24 hours in southern Minnesota with 6-9" reported in some spots (150-225 mm)

    Very sharp northern edge to this rain shield slowly advecting north towards Winnipeg this afternoon.

    As of 3 pm, looks like the northern edge of the rain was around St Adolphe. Should be raining in Winnipeg by the evening rush hour.. just in time for my daughter's soccer game this evening (which I'm sure is the reason for this rain pushing further north than earlier expected.:) Could see 5-15 mm here in the city as Scott mentioned, with heavier amounts of 15-30 mm over the southern valley. Rainfall rates of about 3-5 mm/hr currently falling south of Winnipeg, with Morris up to 12 mm as of 3 pm.

  6. Heaviest rainfall totals of 1 to 1.50 inches midnight thru 6 pm thursday in area from north of bismarck through devils lake-coooperstown-grand forks. with heaviest rain axis likely to shift into far nw mn and se manitoba this eve.

  7. Did an updated PNS on rainfall totals midnight to 7 pm Thursday. Click on my name. Highest totals so far approaching 1.8-1.9 over eastern north dakota west and northwest of fargo up through devils lake and grand forks area. Expect a fairly uniform 1.50 to 2 inches area wide before all is done.

  8. Wonderful!!
    That's the last thing anyone needed was a soaking like that!

    Could be worse....10.75 inches of rain in one area of Southern Minneasota.
    Talk about a flood of biblical proportions!!!

  9. Steinbach had 30 to 40mm of rain (depending on which gauge you check). Morris and St. Pierre had 50mm, with Sprague near 60mm. That puts Morris at 150mm for the month and 250mm in the last 26 days!

  10. Ended up with 22 mm here at my site, quite a bit more than I was expecting with this event which models kept indicating would stay mainly south of the city. I'm now over 100 mm for the month, the 4th month in the past 5 with over 100 mm rainfall total. What has really driven the totals this year has been the quantity of rain with these events, rather than the overall frequency. On average, Winnipeg sees 3 days a year with daily rainfall amounts of 25 mm or more. We've had 6 so far at the airport, with more elsewhere in the city. It seems like there's considerably more moisture in the atmosphere to work with this year which has increased storm rainfall amounts. This seems to be the case in many places this year, not just here in southern MB.

  11. The years 2000 and 2005 had similar patterns of extreme rain (> 200mms) in the same month (or at least within 35 days) but they were in Jun 2000 and July 2005

    See. Significant rainfall events from previous years

    I suspect this sets a record for Annual rainfall and also Total precipitation for a complete Calendar year. Nearest to this year I could find were
    1962 590.7
    1968 586.6
    1977 633.5
    2000 621.6

  12. Previous post shows total rainfall.

    Total Pcpn for the 4 greatest years I could locate is
    1962 723.3
    1953 718.6
    1977 715.0
    2000 701.6