Wednesday, May 07, 2008

Cool weather continues

The cool start to May continues into the second week, and it looks like below normal temperatures will likely stick around through at least mid month. Temperatures so far this May have been running about 3-4 degrees below normal over southern MB, with little in the way of warm days so far. Through today, Winnipeg has seen only two days of 20 degree plus weather this year, both in April. In contrast, last year we already had ten 20C days by May 7th. In fact, a year ago this Friday, Winnipeg hit its first 30 degree day of the season with a record high of 31c. No such luck this year as the North American storm track continues through the central plains, and the southern Prairies remains on the cool and dry side of the storm track. This has led to a slower start to the growing season here.. running about 1-2 weeks behind last year.

18 comments:

  1. The folks in Calgary just can't get a break. 10 to 20cm today, and cold temperatures. Comparing that to us makes me feel a bit better, at least it isn't snowing!

    Then again we did triple our average May snowfall a little while ago.

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  2. A 60 percent chance of snow of Saturday!!!
    Just wonderful!!!!
    I love May in Manitoba!!!!
    Brandon is calling for 10 - 15 cm of snow tomorrow!!

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  3. Models have had a heck of a time trying to figure out what's going to happen this weekend. They've been flip flopping between snow/no snow over us for Saturday over the past few runs. Latest concensus shows a disturbance bringing snow over srn SK into SW MB Friday into Friday night.. but then the whole mess shifting south of the MB border during Saturday with yet another snowfall possible over North Dakota this weekend. Unbelievable how we can't shake these late snowfalls this spring..

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  4. The prediction of a nice ridge of high pressure moving in for next weekend is still holding. It will bring temperatures in the 20 to 30 degree range for the Prairies. In South-Western Manitoba next weekend CAPE values will reach above 1000 J/kg so some severe storms are possible. Wind shear doesn't look all that great right now, but that can change easily. I am still holding out on Brett Anderson's prediction of an above-average second half of May. Hopefully those warmer temperatures will also bring along severe weather ingredients!

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  5. Looks like a nice rain potential coming early next week. Sure it may bring more cooler temps if it does come, but I don't care; I'd rather jut get that moisture in the ground.

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  6. That warmup for next week looks nice.. just in time for the May long weekend! Of course, that warmup is in model land.. hopefully it works out in reality. I'm getting tired of wearing parkas to the kids soccer games!

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  7. Brett Anderson's current update looks grim. According to the European long-range forecast model the below normal temperatures are expected to last into JUNE! If this plays out and we get a 2005 style summer (wet and cold) I probably won't be able to contain my frustration. You wait all winter just to see wet and cold conditions...Ridiculous!

    He says the reason for this is a block over Labrador. Rob could you explain why high pressure in Labrador could ruin an entire month..and how high pressure can dominate a region for such a long period of time.

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  8. In all honesty, I seriously do not believe any long range summer forecasts one bit at all. Why? Because after looking around, I see different predictions each time.

    Environment Canada says hot and wet Summer, Brett Anderson says cold and wet Summer, and Larry Cosgrove says hot and dry Summer for us here in Southern Manitoba.

    The predictions are all saying different things, how do we even know if any certain one is right?

    I'm just going to wait and see what Summer has in store for us as it arrives.

    Jon

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  9. Long range forecasts are always a crap shoot.. especially Prairie summers which can be so locally affected by soil moisture conditions and convective precipitation rather than large scale weather influences.

    I see Brent Anderson is talking about the influence of a "weak" blocking high over Labrador.. with, presumably, a persistent Hudson Bay vortex which would maintain cooler than normal temperatures in MB. But the fact that he's calling it a "weak" feature throws some doubt on the confidence of this pattern persisting. Some patterns are more persistent than others (depending on the number of Rossby waves circulating around the globe) but its always difficult to predict when there will be a breakdown in the overall pattern.

    Bottom line, I'm with Jon.. I wouldn't get too concerned yet about a bummer of a summer.. no one really knows what to expect at this point.

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  10. Yet another snowfall to our south.. Grand Forks and northern MN getting snow this morning! As rotten as our spring has been so far.. it's been far worse south of the border. This is their fourth snowfall since early April... and I belive every one of them has been at the beginning of a weekend!

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  11. GEM showing potential for 15 to 30mm of rain over Southern Manitoba on Monday. At least I can try out my rain gauge!

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  12. What a way to start your weekends in may-with a snowfall. That low producing the snow there is also giving way to a possible big tornado outbreak later today.

    I really do hope we get that rain, it's very needed. We gotta bring that soil moisture level up.

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  13. Models in general agreement that there will be a good chance of showers over Southern MB Monday into Tuesday.. although they disgaree on the overall amounts. NAM showing about 6 mm for Winnipeg Monday into Tuesday, GFS about 17 mm, GLB about 14 mm. Looks like precipitation will be initiated by warm frontal elevated type convection early Monday, evolving into a more continuous area of stratiform rain Monday night as the inverted trof moves through, then finishing up Tuesday with some wrap around precipitation on the backside of the trof. Model precipitation forecasts will be highly variable depending on timing and location of convective development Sunday night into Monday.

    By the way, models have backed off on that warming for the end of next week, as they now show Hudson Bay vortex reinforcing cool air over eastern Prairies, while ridge amplifies over the west. Not good.. warm weather will be delayed yet another week if this works out..

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  14. Both the GEM and GFS are now leaning towards a 10 to 25mm rainfall across Southern Manitoba for Monday into Tuesday. The extreme South-East corner of the province (Sprague) could see up closer to 30mm.

    Winnipeg currently looks like around 15mm, and Steinbach 15 to 20mm. Seems like a good amount of rain for the time being.

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  15. According to the Manitoba Agriculture station the low here was about -8 last night! I don't know if this is correct, considering all the other station around the area reported between -2 and -6 for lows. I think a -4 is more likely and since Winnipeg only got down to -3 I can believe we got 5 degrees lower than them!

    My station only reported -2, and usually is a couple of degrees warmer than out at the airport (like The Winnipeg Airport vs. The Forks)

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  16. Looks like a good dose of rain is coming into the area the next day or so.
    Environment Canada is calling for a INCH of rain in Winnipeg which will for sure green things up!!!

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  17. GEM model which drives the EC forecast is the wettest of the model pcpn forecasts for Winnipeg.. giving us 28 mm by Tuesday morning. Most other models giving us about 10 mm with this event, except 20 mm from the NGM. All depends on the model physics and convective schemes, but GEM does tend to overestimate amounts in convective situations at times. GEM could end up being right, but at this point, it's the outlier on the high side. We'll see what happens..

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  18. I think we will end up with around 20mm tomorrow and 5 to 10mm on Tuesday. Environment Canada is calling for 15 to 25mm tomorrow during the day, and 5mm in the evening/night. Tuesday will likely see another 5mm in the early morning, with more possible. As of 10:00p.m. the precipitation is still quite a ways off of the Red River Valley. I imagine the shield will slowly growing in size and intensity overnight.

    I am interested to see how my rain gauge performs for the first time!

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