Thursday, July 17, 2008

Weekend washout?

Forecasts for the weekend appear rather pessimistic for Winnipeg and southern Manitoba with showers forecast for both Saturday and Sunday and high temperatures only near 20C. But will it be that bad? Other computer models are more optimistic for the weekend showing more typical summerlike weather with only scattered showers and possible thunderstorms over the weekend, but dry most of the time, along with some sun and increasing humidity. The Canadian GLB seems to be the most aggressive with an impulse moving through the northern plains, generating a wide swath of heavy convective precipitation over southern MB. Who's right? We'll have to see what the trends are over the next run or two, but at this point, I'm thinking this weekend will not be a total washout as the GLB suggests, with partly sunny skies, more humid conditions giving scattered showers and thunderstorms at times, and high temperatures in the 22-25C range. Rest assured, this will not be a repeat of last Saturday's wet and wild weather!

26 comments:

  1. Rob, interested in your take on the article in the Free Press a couple days ago. It suggested we are on the verge of a real warm up and a much better second half to our summer

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  2. I'm an optimist.. and think we will be warming up next week and we'll see 30C before the month is over. I also think that summer ain't over and August will be warm.. but that's just more hopeful than scientific! But we've been generally below normal for almost 6 months now.. surely the pattern's gotta change sometime soon, doesn't it?

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  3. Yes a weekend washout for some in southwestern Manitoba with a heavy rainfall warning!
    50 mm of rain is expected!!

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  4. Models had difficulty resolving what will happen with that BC upper low as it finally moves west. It still appears that the upper low will split into 2 main shortwaves. The northern wave will get sheared out and weaken as it moves into NW Ontario. However the southern wave will tap into a well defined low level jet and move towards S Ontario. The models are once again advertising a bimodal precip pattern.

    Watch for a an MCS to form in Minnesota on the nose of the low level jet as it swings into the Great Lakes by early Sunday. Models take the MCS north thru the muskoka area along the 850 MB warm front.

    Despite the northern wave losing its definition and its poor linkage to the main low level jet... models depict another MCS to form in its vicinity. Should be over S Manitoba by tomorrow morning.. will the lift associated with the wave be enough even with all the shear and better jet stream dynamics over the US? Could be some redevelopment along the associated surface trough in Minnesota as it moves east. Lets see what happens.

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  5. This summer has been absolutely brutal!

    The average temperature so far is 23.3, and in 2004 (supposedly the coldest summer on record) the average was 24.6!..then again the average in August 2004 was a mere 20.3...OUCH!

    Even if we get a spell of really hot days (which isn't in the forecast) I doubt we will be able to dig ourselves out of the hole we are in. Looks like we can almost guarantee another below-normal month...lets hope August will be better!!

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  6. What about the updated forecast for the next week up until about Saturday? 24-26C instead of upper 20's? (see Winnipeg forecast on TheWeatherNetwork). Normal if not slighly below?

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  7. Maybe we're not having global warming. Maybe we're moving back into an ice age like we supposedly were in the 70's.

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  8. I don't know whether you believe in Global Warming or not, but it always gets me angry when people question it after a cold winter or summer.

    The basic point of climate change is the BIG picture. We may have the coldest winter on record here in Winnipeg, but at the North Pole they may be having one of the warmest on record. Perhaps in the Sahara region the temperature has been 4 or 5 degrees above normal this year...

    No matter what happens in one region it has nothing to do with the overall climate. It is all the weather and climate stations around the world added together that will determine the effect on the global climate. The projections I have seen predict that Winnipeg has equal chances of having a warmer or cooler climate than now due to global warming. On the other hand more places will experience warmer temperatures than now, out- balancing the cooler regions, creating a warmer global climate.

    I just had to through that out there, people need to realize the weather (the here and now) has nothing to do with global warming, it is the overall weather and climate of the world that makes a difference!

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  9. To follow up on Scott's point about climate change and the inherent variability in weather... here is an interesting story from Nunavut:

    http://www.weatheroffice.gc.ca/warnings/SWS_bulletins_e.html?prov=nu

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  10. I also read that Special Weather statement for Iqualuit. It is interesting how much warmer it seems to have been there in past years. Perhaps less sea ice earlier is allowing for maximum heating during peak summer hours, the presence of warmer water probably also helps.

    On a side note...Churchill's high tomorrow is 32, wouldn't that be something if Churchill had its first 30 degree high before Winnipeg!

    I also spelled throw wrong (through) in my last post...just to let all you grammar critiques know (ha ha).

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  11. The comment was made in jest But I do find it interesting how many people get mad when someone points out the cooler temperatures but when someone points out the warmer temperatures that becomes proof positive. I do agree with you that the only way is to add up the data from all the weather stations to find the overall trend.

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  12. I wasn't sure what you meant, but I thought I would say that anyway because I find comments like that almost anytime somebody hears of a cold summer/winter.

    That wasn't a person attack on anyone, just a comment to set the record straight.

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  13. I agree with you both, I'm pretty tired of people saying one day that it's never been so hot before and the next day saying global warming is a lie.

    It's clear that we're in a warming trend, wether we have to do something with it (or a lot) or not is the big unanswered question in my opinion. But you can't deny the evidence, that is, the data.

    What annoys me is that quite a lot of people don't understand that no matter you're living in a hot or cold era, there are always hot and cold summers and winters. As Scott said, don't confuse climatology with meteorology!

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  14. This makes me laugh and sigh all at the same time...the headline reads:

    CHURCHILL REACHES 30 DEGREES BEFORE WINNIPEG IN 2008!

    Yes it is true, as of 1 p.m. Tuesday, July 22, 2008 Churchill, Manitoba records a high of 30 degrees Celsius. Although I cannot confirm whether this was actually 30 (it may have been 29.7 or something like that) later in the afternoon the town reached a high of 31, meaning that 30 obviously has been achieved.

    With a mighty South-West wind of 40 km/h gusting to 60km/h it happened, Rob has this ever happened before? If so I doubt it has happened many times. That is 13 degrees above normal for Churchill, whereas in Winnipeg we can't squeak out a measly 4 degrees above normal, INCREDIBLE!

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  15. The official data from Environment Canada says they hit 31.4 in Churchill. Pretty hot for that far north.

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  16. Hey, What are the trend models saying for August? like in temperture and in Precip. because really it hasn't been that active with thunderstorms in manitoba and since we are almost done summer could we still see some very hot tempertures?

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  17. I sure hope the long rage GFS is right!

    It's forecasting temps in Southern Manitoba to climb to 100-105 F!

    That's about 38-41 C , also that's without humidity and resulting humidex added on!

    I sure hope it's right, because I miss the major Summer heat!

    Not to mention, the model also hints at a severe weather episode along with those temps!

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  18. There is certainly some major heat in the forecast...but that doesn't necessarily mean severe weather in my opinion.

    The reason I say this is due to the upper air temperatures. At the surface it may be 35 degrees, with a DP of 25, creating extreme CAPE values (just as an example). With the warm upper air temperatures needed to create those extreme values the capping would likely be too strong to create severe storms. However at the end of the heat wave a low pressure system will likely move, ushering in colder upper temperatures and therefore breaking the cap. I would see the most likely scenario as being a good stretch of really warm temperatures, followed by a big severe weather outbreak at the end. It is really teasing to see those high CAPE values over us, when they can't even by utilized!

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  19. The sky looks a little hazy today, is this from thin clouds or forest fires?

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  20. It's from forest fires from northern saskatchewan, A northern wind is blowing the smoke towards western Manitoba.

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  21. Interesting situation...which is hardly surprising.

    The GFS indicates that warmer temperatures are in store for the next couple of days. However it doesn't look very likely that the Winnipeg airport will reach 30 degrees this July.

    My only question is whether or not this has happened before? Even in the somewhat miserable 2004/2005 summers we easily passed 30 in July. This is absolutely incredible, once again I ask whether this has happened before...I neither have the time nor patience to sift through years of weather data, but I am sure Rob would know!

    P.S. Just to brighten/dampen your spirits, here are the past four July 25 highs:

    2004: 29.3
    2005: 19.9
    2006: 27.0
    2007: 35.3

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  22. Scott.. Look back at July 1992 and that should make you feel better about this year. That July, Winnipeg's warmest temperature was a measly 26.7C. Only 3 days hit 25C or more the entire month. Average high for the month was 21C.. some 5 degrees below normal. Rainfall above normal.. sunshine way below.

    This year, we've at least had some warmth, even though it hasn't hit 30C at YWG airport. Average high has been 24C, 3 degrees above 1992's average. We'll hit 25C or more at least 10 times before the month is over. Rainfall has been below normal, and sunshine has been average. So all in all, we're doing a lot better than we did in 1992. Overall, this July has generally been a comfortable month.. a lot of people don't mind the lack of extreme heat.

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  23. That is true, for people like me the heat is sometimes simply a symbol, rather than a comfort zone. The lack of strong thunderstorms in the Red River Valley this year also seems surprising. Perhaps it is just a shock back to reality after coming off of such an active summer last year.

    Hopefully August will finally be above average, at best this July will probably only come close to average.

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  24. 29 C
    LETS hit 30 C today!!!!!!
    We are so close
    I wonder if we will make it!!!

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  25. We unofficially got to 30 in Steinbach today (29.7C).

    Looks like Winnipeg may get the chance early next week!

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  26. Theres a big tornado watch in saskatchewas, is this risk coming to manitoba tommorow? I hope not.

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