Friday, April 27, 2007

Summerlike Saturday

Looks like a beautiful Saturday shaping up over Southern MB and the Red River valley with plenty of sunshine and a balmy southwest flow sending temperatures up to the 25C mark in many localities including Winnipeg. The sunny skies, low humidity and dry soil conditions along with a favourable southwest flow will make for ideal conditions for a warm day, with temperatures of 27C possible along the western Red River valley from Portage through Morden to Gretna and Emerson. Should be a beauty for enjoying the outdoors.. although area farmers are likely not enjoying this sunny dry weather. We sure could use some rain to start replenishing soil moisture levels which are getting pretty low in areas. After another sunny dry day Sunday, it appears that southern MB may see some rainfall on Monday as a disturbance passes through the area with showers and possible thunderstorms. Models are indicating a general rainfall of 5 to 15 mm over southern MB, with locally higher amounts possible in thunderstorms. Not a drought buster.. but anything will help at this point!


  1. Officially a high of 26.7C at YWG airport today (or 80F on the old scale).. our warmest April day since April 29 2001 (28.3C) Sure was a nice one! Sunday won't be quite as warm, but with more sunshine and afternoon temperatures near 20C.. it will still be another ideal day for outdoor activities.

  2. By the way.. very low humidities over Southern MB today with RH values below 20% this afternoon in most areas including Winnipeg. RH was down to 15% in some spots with temperature-dew point spreads near 30C! (Melita had a 27C air temperature and a dew point of -1C for an RH of 16% late today)

  3. Hi Rob,

    How much rain do we need to normalize things?

  4. Justin..

    If you go back to last year, we had about a 200 mm rainfall deficit from April through October (about half the normal 400 mm we should have received over that period). Snowfall from October 2006 through March of this year was about 20 cm above normal (or roughly 20 mm melted). March 2007 had about 20 mm rainfall above normal.. so putting it all together, we're starting the growing season with a roughly 160 mm precipitation deficit since April of last year. This is based on Winnipeg precip stats, which will vary across southern MB but should be fairly representative for much of the Red River Valley. Note that April this year has been very dry, with only about 10-15 mm of precipitation compared to an average 32 mm. So we're already starting the year behind.

    Now normally, southern MB sees most of its rainfall between May and July. It's possible that we could make up this deficit in that time period, but the pattern would have to change to a more unsettled southwest upper flow with storm systems tracking across the Dakotas bringing showers and thunderstorms across the southern Prairies. Whether or not this happens, we'll have to see. (It doesn't take much for a major pattern flip to occur.. it does happen from time to time)

    One thing's for sure, if we don't see normal to above normal rainfall within the next 8 weeks, area crops could be in serious trouble. And don't forget that we need surface moisture to generate rain.. the drier the surface, the more difficult it is to start the cloud formation/precipitation process.

    Note: YWG airport has been over-recording rainfall in March and early April due to a snow shield that was still on the rain guage. This resulted in rainfall readings twice what they should have been. For example, on April 1st, YWG airport recorded 24 mm of rain and wet snow, when in reality, only about 10-12 mm fell on the city. Something to be aware of if you're tracking precip stats from Winnipeg airport.