Saturday, June 30, 2012

A hot and sunny Canada Day on tap.. thunderstorms possible Monday

It's going to be a hot and sunny day for Canada Day celebrations in Winnipeg and southern Manitoba Sunday. Temperatures are expected to hit the 30C mark Sunday afternoon under blazing sunshine and light winds, so don't forget the hat and sunscreen if you're out! Fortunately, humidity levels will be tolerable with afternoon dewpoints in the mid teens expected. By late Sunday, thunderstorms are expected to fire up over southern Sakatchewan, possibly severe. These storms are expected to track across southeast Saskatchewan into southwest Manitoba Sunday night into early Monday, before weakening somewhat as they push into the Red River valley by midday Monday. Additional thunderstorms are possible later Monday over southern Manitoba depending on how much morning activity clears. Sunny and hot weather is expected to return Tuesday before another threat of thunderstorms moves in Wednesday.

90 comments:

  1. Will be interesting to see how early it clears on Monday, with the NAM showing LI at -11.2 and CAPE reaching 4000, and dewpoint above 20C. GEM is a little more reserved.

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  2. It's getting too dry in South St. Vital.

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  3. Good day to be poolside or at the beach today.. blazing sunshine, and very little wind to ventilate things. Dewpoints are higher than I was expecting.. around 20C in Winnipeg right now due to the almost calm wind which is preventing ventilation of drier air. Dewpoints will likely drop a bit this afternoon with a little bit of mixing, but otherwise.. a scorcher out there today! Stay cool everyone and Happy Canada's day!

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  4. 28C at the airport as of noon, but most backyard stations in Winnipeg are over 30C already (including mine) due to the strong sun and lack of wind to mix things up. In this case, backyard stations are giving a more realistic indication of how hot it really feels out there. I can just imagine how hot it is out on Osborne street today!

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  5. Whats the chances of rain or thunderstorms at grand beach tomorrow?

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  7. NAM is showing CAPE values over 4000 J/Kg and LI's near -11 tomorrow afternoon. Might get huge severe storms, what do you think Rob?

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  8. huge severe? lol

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  9. Correction: NAM is showing CAPE values over 4000 J/Kg and LI's near -11 tomorrow afternoon. Might get some powerful storms, what do you think Rob?

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  10. Tomorrow's tricky.. we have a chance of some elevated thunderstorms popping up over SE SK and SW MB overnight into Monday morning which would push a lot of cloud and possible showers into Winnipeg/RRV by midday.. which would limit the amount of heating and instability for us in the afternoon. If overnight activity is not as extensive or weakens quickly, then we have a better chance of seeing hot and humid conditions over us Monday, with low 30 temps and low 20 dewpoints which would generate those high CAPE values. Even so, there's a pretty good cap over us with a lot of warm air aloft, and low level forcing is not the greatest to overcome the cap and initiate storms. There is some shear to work with and lift from an upper trof moving through which would help to break the cap and trigger some storms in the afternoon.. but timing may be better south and east of Winnipeg.

    Bottom line, a bit of a mess.. but potential for some strong to severe storms if things line up. Better assessment tomorrow morning based on overnight activity and morning soundings.

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  11. Rob,

    Question...

    I hear of a better severe weather threat for us wednesday..what is the latest on that potential threat?

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  12. Looks like one of the forecast sattelite models are predicting that some of the morning cloudcover from the elevated storms that are forecasted tonight in Saskatchewan will clear out by 10Z. This will likely give us a chance to heat up providing a great atmosphere for thunderstorm development, depending on the Cap strength.

    Again it all depends on how things play out in the morning.

    Feel free to have a look by clicking My name....

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  13. Models are not typically very good at forecasting the remnants of nocturnal thunderstorms.

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  14. Yeah, overnight and morning MCS activity is a crapshoot when it comes to the models. June 9th is a great example. The HRRR was the only model that showed a big MCS pushing across southern MB. It latched onto the idea late Friday night.

    Tough to say how the MCS will organize and how it will behave tomorrow morning. We'll have a much better idea tomorrow morning, like Rob said.

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  15. Cap (or Capping Inversion) - A layer of relatively warm air aloft (usually several thousand feet above the ground) which suppresses or delays the development of thunderstorms. Air parcels rising into this layer become cooler than the surrounding air, which inhibits their ability to rise further. As such, the cap often prevents or delays thunderstorm development even in the presence of extreme instability. However if the cap is removed or weakened, then explosive thunderstorm development can occur. sounding.

    The cap is an important ingredient in most severe thunderstorm episodes, as it serves to separate warm, moist air below and cooler, drier air above. With the cap in place, air below it can continue to warm and/or moisten, thus increasing the amount of potential instability. Or, air above it can cool, which also increases potential instability. But without a cap, either process (warming/moistening at low levels or cooling aloft) results in a faster release of available instability - often before instability levels become large enough to support severe weather development.

    CAPE - Convective Available Potential Energy. A measure of the amount of energy available for convection. CAPE is directly related to the maximum potential vertical speed within an updraft; thus, higher values indicate greater potential for severe weather. Observed values in thunderstorm environments often may exceed 1,000 joules per kilogram (j/kg), and in extreme cases may exceed 5,000 j/kg. However, as with other indices or indicators, there are no threshold values above which severe weather becomes imminent. CAPE is represented on a sounding by the area enclosed between the environmental temperature profile and the path of a rising air parcel, over the layer within which the latter is warmer than the former. (This area often is called positive area.)

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  16. Just wanted to let people here know that it looks like we'll have 2/3rds of AWM out chasing tomorrow. Stop by http://aweathermoment.tumblr.com and check out the forecast, as well as updates from our chasers in the comments / a live twitter feed!

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  17. Good stuff Brad.. we'll be virtually tagging along with you!

    Slight risk of severe storms over southern MB and eastern Dakotas today.. hinging on what happens with the remnants of the overnight convection off to our west. Ample moisture in place with dewpoints in the low 20s today.. wild card is how much sun will be available to trigger convection this afternoon. Feeling is that there should be enough dissipation of cloud to get us into the low 30s, which would be provide enough energy to trigger storms. Moderate shear, and lift from a weak trough with upper support should be enough to fire up some tstorms over RRV and SE MB this afternoon.. with strong wind gusts, hail and heavy rain as main threats.

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  18. By the way, June 2012 ended up with an average of 17.8C at YWG airport, or 0.8C above normal. We've now gone 12 straight months with a monthly temperature above normal (although May was only 0.2C above normal, it was still above). This makes the last 12 months the warmest 12 month period in Winnipeg history at 5.93C. Weather records began here in 1872.

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  19. Today looks like a pretty potent setup over Southern Manitoba and North Dakota when it comes to severe weather. Many features that brought a line of severe storms to Saskatchewan yesterday, which produced large hail and a few tornadoes, look to rest over south-central Manitoba/eastern North Dakota by this afternoon. We'll have a few features in place that may hinder strong convection today, but by all counts, the potential exists for a strong-to-severe storm breakout over the Red River Valley.

    Some cloud cover will advect in over the next hour or two, remnants from the convection in Saskatchewan, and inhibit daytime heating for 3-4 hours. Some of it will burn off as it passes through, so the sun may peek out here and there. This feature is by far the single greatest chalenge to the convective forecast today: if the clouds don't clear out by early afternoon then there's a good chance that there won't be enough daytime heating to trigger the storms. If it does clear out, though, look for daytime highs near 32°C today with a sticky dewpoint as high as 23°C, making it feel much closer to 40 than 32°C.

    If we get our afternoon heating, all the parameters are in place. CAPE values are progged to be 2750+ J/kg (perhaps as high as 4000 J/kg), lifted index values near -10 will be in place over much of Southern MB and E. North Dakota, a strong upper-level jet will be in place giving us 50 knots of deep shear, and 0-3km EHI values look to promote the development of supercells through much of the region.

    Fortunately for residents of Southern Manitoba, a developing surface low in North Dakota will back winds over S. MB slightly this afternoon, while developing an increasingly strong SE flow over much of the eastern portion of the state. Based on the positioning of systems, combined with the model-progged 0-1km EHI values, I'd say the highest risk for tornadoes will remain on the US side of the border, from Central North Dakota then sliding eastwards through Grand Forks/Fargo into central MN. On our side of the border, the favorable deep-shear and helicity will still likely develop supercells, however the greatest threat will be large hail (golf balls to baseballs under the big storms), strong winds, and the potential for localized overland flooding due to heavy downpours. These threats also exist in ND/MN.

    A graphical outlook for today is attached and available here: http://cl.ly/Hnvx

    If sharing please link back our blog ( http://cl.ly/Hp6j ) for additional context to the graphic.

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  20. Extreme instability values (over 4,000 J/KG) already in parts of southern Manitoba. Could get very interesting this afternoon!

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  21. When do you think this cloudcover will clear out?

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  22. Someone needs to issue a humidex advisory asap ;)

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  23. Humidex advisory just issued..

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  24. Rob,

    question....

    Severe tstorm watches and warnings are only in effect south of transcanada highway along the american border today..does this basically mean the severe weather threat will remain there for today given us virtually no chance of seeing storms at all today?

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  25. @Anon:

    I wouldn't be surprised to see that watch expand northwards once (if?) the clouds clear out of our region. Personal opinion: there's definitely a threat for severe weather through much of southern Manitoba (see: http://cl.ly/Hnvx ).

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  26. I think we can still see some storms in Winnipeg today.. but the main action will be to our south which will rob us from our severe potential today. We will need to clear out of this convective debris quickly this afternoon to have a chance of more severe storms over Winnipeg, but at this point, that doesn't look likely. Sure would be nice to get a good storm to give us some rain, and maybe cut these oppressive conditions today! Awful out there!

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  27. Some cells beginning to fire up near the Lac du Bonnet area.

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  28. Think the cloud cover has ruined the chances for Winnipeg today. Temp has dropped a few degrees here at my station also. Too bad, I was going to take the kids for a chase!

    Dan

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  29. Watch got expanded.

    SEVERE THUNDERSTORM WATCH FOR:
    =NEW= BISSETT - NOPIMING PROVINCIAL PARK - PINE FALLS
    =NEW= WHITESHELL - LAC DU BONNET - PINAWA
    STEINBACH - ST. ADOLPHE - DOMINION CITY - VITA - RICHER
    MORDEN - WINKLER - ALTONA - EMERSON - MORRIS
    SPRAGUE - NORTHWEST ANGLE PROVINCIAL FOREST
    KILLARNEY - PILOT MOUND - MANITOU.

    THERE IS A RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
    EVENING.

    THIS IS AN ALERT TO THE POTENTIAL DEVELOPMENT OF SEVERE
    THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS.

    MONITOR WEATHER CONDITIONS..LISTEN FOR UPDATED STATEMENTS.
    IF THREATENING WEATHER APPROACHES TAKE IMMEDIATE SAFETY
    PRECAUTIONS.

    IF YOU WOULD LIKE TO REPORT SEVERE WEATHER, YOU CAN CALL
    1-800-239-0484. PLEASE NOTE, THIS PHONE NUMBER IS ONLY FOR
    REPORTING SEVERE WEATHER.

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  30. So its the cloud covers fault. We get the left over garbage cloud cover from a weakend system which further robs us from getting anything further. Talk about insult to injury

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  31. By the way, a head's up, if you're seeing a new design on the NWS' page if you're looking for what warnings are in effect down south, you're not hallucinating or on the experimental site.

    Just thought I'd let people know that they've made it live.

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  32. This summer is more and more becoming a déjà vu of summer 2011 lol.

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  33. Very unfortunately imo

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  34. SEVERE THUNDERSTORM WARNING FOR:
    =NEW= R.M. OF REYNOLDS INCLUDING HADASHVILLE AND RENNIE.

    AT 1:50 PM A POTENTIALLY SEVERE THUNDERSTORM WAS LOCATED NEAR
    HADASHVILLE MOVING NORTHEAST AT 60 KM/H. NICKEL SIZE HAIL AND
    WIND GUSTS TO 90 KM/H ARE POSSIBLE WITH THIS STORM ALONG WITH
    TORRENTIAL RAINFALL OF 25 MM IN A SHORT PERIOD.

    THIS IS A WARNING THAT SEVERE THUNDERSTORMS ARE IMMINENT OR
    OCCURRING IN THESE REGIONS. REMEMBER THAT SOME SEVERE
    THUNDERSTORMS PRODUCE TORNADOES. LISTEN FOR UPDATED WARNINGS.

    IF YOU WOULD LIKE TO REPORT SEVERE WEATHER, YOU CAN CALL
    1-800-239-0484. PLEASE NOTE, THIS PHONE NUMBER IS ONLY FOR
    REPORTING SEVERE WEATHER.

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  35. So so SO sick and tired of this constant repeat scenario of everything missing us!! When will things ever change?? I don't remember it ever being this bad!

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  36. clearing skies showing up on Sattelite, we still have time for severe weather. It is also still quite humid in areas where the sun is shining, don't give up hope!

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  37. Just seems like everything is over for us now with the main front passing through dry and moving east and the winds shifting to the west. Hoping now for that untypical scenario where storms sometimes fire up behind the front despite all odds against you!

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  38. Those new NWS pages look pretty slick.. nice new design. Info is laid out better, and easy to find.

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  39. Rob,

    I noticed a wind shift to west this afternoon but it remains incredibly humid...humidex around 40..are thunderstorms chances for us diminishing as the day goes by with frontal passage going through

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  40. Anon.. Yes, our winds have shifted to the west, but the drier air is back over western MB and southern SK, so it will take a awhile before we see our dewpoints drop into the teens. As a result, we'll stay with those 40C humidex readings into early this evening before things cool off a bit after sunset. Dewpoints should be a bit lower Tuesday (mid teens instead of low 20s) so Tuesday's 30C heat shouldn't feel as oppressive as today. Once you get dewpoints over 21C, you are just melting out there..

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  41. Rob, a question for you about warnings. Why do warnings have no stated expiry time? There's the exception of southern Quebec, but why isn't it included nationwide?

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  42. Man, if only there was a sounding from Winnipeg today.

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  43. Connor.. EC is moving towards a new warning program in which warnings will have expiry times mentioned. The new program was to have started this month but has been delayed due to technical issues. However, the plan is there to have valid times in future warnings.

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  44. Rob,

    question...

    With today's thunderstorms chances pretty much finished what does wednesday's potential bring, any severe weather chances?

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  45. or let me guess, something will throw a wrench in that potential as well like what's been happening so far this season...looking alot like last year...storms either miss us to the west east or south or no storm development at all.

    another question Rob...

    Why is the cap always so strong here? in Saskatchewan it seems like storms have no trouble blowing the cap, what's different here?

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  46. I reiterate the post above and are wondering about the same thing

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  47. Have a cell starting to pop west of the city just south of Elie.. ain't much, but something to monitor.

    Anonymous.. Wednesday looks like another marginal day for us. Front is coming through at the wrong time.. around midday.. for anything really severe. Looks like we'll be getting leftovers from a line of convection that will be firing over southern Saskachewan Tuesday, with a good chance of severe storms there Tuesday afternoon/evening.

    As for why Saskatchewan seems to get more severe storms than us, they are closer to the west Coast upper trof which does two things.. 1) brings in colder air aloft which destabilizes airmass (as well as weakens the cap), and 2) brings in stronger winds aloft (shear) These help to increase chances for severe thunderstorm development. Further east in southern Manitoba, we are often under an upper ridge when the West Coast trof comes in, which tends to bring warmer air aloft over us (stronger cap) and pushes the jet stream winds further north (less shear) This lessens the chances for severe storms over us, until we get a good upper trough moving through at the right time of day.

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  48. the term thunderstorms i find is used a little too often in the forecast for the very little of it that we actually do see especially here in Winnipeg. It's pretty hard to take the forecast of severe weather seriously whenever it's talked about here because 99% of time nothing happens and for us here in Winnipeg if severe storms do form by the time we see them they've pretty much fizzled out. We definitely are not in a good spot for those who love storms. Unlike here, in SSK when severe weather is forecast it actually does occur. We saw more storms bach in March through May then now and at that time it was much cooler. Something definitely wrong with that picture. We've been listening to this supposed more active pattern for us for weeks now and yet we still are waiting for it..time to drop that notion i think...really starting too look like 2011

    Rob, what's your opinion on this?

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  49. Outflow boundary coming thru with some towering cumulus.. cell popped NE of the city but not much else.

    We definitely need the rain after June finished below normal for precipitation, and with no measurable rain in 2 weeks.

    Daniel

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  50. I'm a little disappointed that we didn't see storms in the city today, but not because I like storms.

    The forecast worked out...alright. Severe storms pushed across the southern RRV this morning, however a lot of cirrus blowoff prevented us from heating up enough before the trough swung through this afternoon. Further east in the Whiteshell, which had a couple more hours of sun than we did, absolutely exploded as the trough moved in.

    The reason I'm a little disappointed is that today -seemed- to be our best shot to get some precipitation. We haven't had any measurable precipitation for a couple weeks now, and Wednesday doesn't look too promising (unless the whole system slows down a bit and comes through later). After that it looks...dry. After a very wet few weeks at the start of the growing season, not getting any precipitation for another couple weeks could be quite devastating to many plants that haven't had to develop a bigger root system, instead focusing on top growth with the ample water supply.

    Here's hoping for Wednesday, and perhaps that the upper ridge will break down a little sooner than later so perhaps we could even get an actual synoptic rainfall event over all of Southern Manitoba, not just convection.

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  51. Anonymous.. Every year is different. I wouldn't throw in the towel on this year just yet.. plenty of time for good storms here, at least through the next 4-6 weeks. (although I admit that the prospects of a hot dry summer just to our south may limit thunderstorm potential here) Patterns can change, which can be difficult to see ahead of time. Note also that the odds of a getting a severe thunderstorm at your exact location are pretty low in any year. Even though the setup may be good, we're still talking about a small scale phenomenom that you need to directly hit your location. Not as common as you may think. I've been in Winnipeg for 12 years now.. and I can probably recall 4 or 5 severe storms that I have encountered here. When I moved here, I thought I'd be seeing great thunderstorms every year.. but that hasn't been the case. Just have to be patient.. or find a chase team :)

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  52. A couple of points re severe tstorm/ heavy precipitation for Winnipeg..

    As Rob stated, during the cold low season, which usually runs from May to the end of July, disturbances will pass off to our NW or weaken to an open wave as they move thru.. robbing us of upper support and dynamics.

    The other aspect to remember is that Winnipeg is at the bottom of a flat, featureless basin. There is a down-slope trajectory from almost every conceivable direction towards the city. We are away from the effects of the Manitoba and Pembina escarpments to the west, lake breezes to the north, and upslope terrain, dark trees, in the Canadian shield out east. This produces that bubble effect we see here so often suppressing surface based convection.

    Additionally, smaller scale waves often pass just to our south across the northern plains and upper midwest. These systems tap the LLJ and low level moisture/instability transport. They are associated with nocturnal MCSs that frequently pummel the midwest. I'm sure the occurrence of those systems falls off dramatically near the Canadian border.

    Daniel

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  53. Thanks for the info guys... I guess it's just a matter of positioning and timing.

    rob,

    as far as the prospects of a hot dry summer just to our south, does that include us as well here in Southern Manitoba?

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  54. Just in reply to all the action Saskatchewan seems to be getting, climatically Saskatchewan is drier than Manitoba. Always has been and always will. If they had more storms then us then their climate would be wetter which it isn't. I don't think all this activity is normal for them. Normally I would think Manitoba is better for storms since our access to gulf moisture, the main perpetrator behind our summertime thunderstorms, is closer. What do others think? I just don't think any of this is normal.

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  55. What an absolute BUST today's public forecast was!

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  56. Re anonymous..

    Even though Saskatchewan and SW Manitoba historically have lower rainfall totals than the RRV, that has not been the case in recent summers.. future trends are unclear. Saskatchewan will always experience more evaporation from westerly flows and low dewpoints than Manitoba however.

    This summer and the past one, we have been experiencing a split pattern.. where cold lows off the pacific are being deflected more to the NW and intensifying due to a strong upper ridge, while smaller waves occlude/split off the upper trough and move across the midwest.

    Daniel

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    1. Thanks Daniel I always appreciate your posts. What makes this scenario extra depressing is there is no chance really after today for any kind of interesting weather to take place as the upper ridge builds again, keeping things dry for another week.

      It's also depressing to learn that we're at an actual geographical disadvantage you'd mentioned about how everything slopes down towards us and we lie too far away from physical features and what not and that we're in an actual bubble that won't ever change the way the weather behaves around here

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  57. We still can get severe surface-based storms here, just a bit less likely than surrounding areas. With a NW flow for example, we can tap convection that forms off the south shore of L Manitoba.. those have been some of the biggest daytime storms in recent years.

    Also, some years the LLJ extends a bit further north into Canada and we get lots of nocturnal storms with heavy rain.

    Daniel

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  58. don't know about the rest of the city but the air quality in Westwood is just awful! Smells like a hog farm out there. What a write off this day has been - too hot to do anything and now the evening air smells like a turd!

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  59. It is a bit frustrating to be in the position we are right now. That's just the way it goes, though. I can't complain much since I got a pretty good storm at 1pm this afternoon. Nice shelf cloud, heavy rain, and lots of lightning.

    Southern Manitoba has had multiple quiet storm years since 2007. 2010 has been the best of the bunch since but not a blockbuster year. 07 stands out for most as the best they've seen and it's tough to argue that.

    05 through 07 was quite nice in southern MB. Of course, we all know what happened in 2007 late in June. Aside from that, there were numerous other great set-ups throughout the summer.

    06 was a scorcher. Big time ridge built over Manitoba and kept us quiet in July. May and parts of June were active on top of the ridge. The pattern broke down or shifted late in July with multiple nice events through August. Overall, a good year for storms.

    05 is my personal favorite. What makes it unique is that it was quite a cool, miserable summer. But we still got numerous good storm events. For those that were around, you may remember some of the big night-time complexes that affected southern MB, including Winnipeg. So many good lightning shows that year.

    Father's Day morning is still my top local storm event. A small MCS that organized in western ND the prior night pushed through early in the morning. Lots of wind damage in the Altona, Gretna, and Letellier areas. Quite the scary experience. I remember the constant flashes of lightning while getting pelted with 100 km/h+ wind gusts and extremely heavy rain.

    The flat US ridge that summer really benefited us. System after system pushed across the Prairies from west to east. It would cool down behind strong frontal passages. We'd then get a day of return flow and hit the upper twenties and increasing humidity as the next front moved through. There were some hot, humid days but not as often as we've had the past few summers.

    July 2 was one of the top events of the year. Dave Carlsen shot this tornado video near Pilot Mound that evening.

    http://www.youtube.com/watch?v=b7u0MsbRJPc

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  60. Thanks for the summary Derek. As you point out, we can get some good years here for storms, but it's not a given every year. At the end of the day, it all depends on how the overall pattern sets up, and that varies every year.. not only here, but in the US tornado belt as well. (look at last year compared to this one..)

    A couple more comments about SK vs MB storms..

    1) Geography: Actual area of southern SK is larger than southern MB. Half our area is taken up by the MB lakes or forests, with a relatively small area composed of wide open Prairies. Compare that to southern SK which is wide open from AB to MB, and from the US border to Prince Albert parklands. In that regard, SK has more open space for storms, while southern Manitoba is more restricted in land space. (kind of like Minnesota vs South Dakota) That alone gives SK an edge in being able to see more storms.

    2) Dynamics: The best severe thunderstorm setups is with a large upper trof pushing in from the west coast with a strong mid and hi level SW jet, overriding a good S-SE moist low level flow. These deep upper trofs typically push in from the Pacific across the Rockies and into the western Plains, before lifting or weakening as they get into the central ccntinent. Thus, pure dynamics tend to favour SK more than MB (obviously not all the time, but often) while MB tends to have better thermodynamics (warmth and moisture) Net result is that supercells are more likely further west where dynamics are often better, with storms transitioning to more multicell or linear type events as you get into southern MB. That's not to say we don't get supercells here.. we certainly can and do.. but in terms of overall setups, I think that SK would have an edge in supercell potential compared to us.

    3) Drylines: Southern SK (especially SW SK) can get drylines advecting in from southern AB, which can be a good focus for thunderstorm development, and tornado potential. Drylines tend to fade out east of Moose Jaw. Thus, southern SK can have a sharper dewpoint gradient from west to east, compared to southern MB which would tend to have a more uniform dewpoint field.

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  61. In terms of supercells it does make sense that Saskatchewan gets more. They do have more tornados on average as well. I'm thinking more general thunderstorm activity whether it be severe or not I would think Manitoba gets more considering we're closer access to golf moisture (same thing when comparing western united states with the eastern united states).

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  62. CBC's forecast is 31C and sunny for Wednesday. Odd.

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  63. One way to compare MB and SK storm wise might be the relative lightning stats for each such as 2005 was the worst/best year btw 1998 and 2008 for Cloud to ground stats.

    Lightning Activity in Canadian Cities

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  64. CTV Winnipeg also shows sunny and 31 tomorrow. They must use the same software.

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  65. Could be interesting tomorrow morning through until the afternoon, EC is forecasting showers with thunderstorms during that timeframe. What do you think?

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  66. This comment has been removed by the author.

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  67. Doesn't look very good Mike! Thunderstorms will go up in northwest Ont. where you were last week.

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  68. EC, The Weather Network, Weather Underground, the Weather Channel, even the Norwegian met service is forecasting thundershowers for Winnipeg tomorrow. Just our own CTV and CBC weather sites have Sun and 31C.

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  69. Ah. CTV just changed their icon, so now CBC is the lone wolf. LOL

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  70. All are on board now with thundershowers tomorrow. CBC just changed their forecast and dropped the temp by 4 C. Better late than never. Now watch it stay sunny and hot!

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  71. John Sauders Forecast is now with the others who are forecasting storms, Including Google weather, Intellicast, Wunderground,Weatherchannel,Accuweather, Weatheroffice, and Weatherbug.

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  72. Keep in mind the forecast you see from CBC is automated on the weekend, as John Sauder is not at work on the weekend. So let's not blame John for not having the storm potential icon for tomorrow. Just a reminder.

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  73. So CBC's automated system had 31C and sunny when all the models showed showers and cloud? Or does it use some other strange model maybe.

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  74. Just caught some live tornado touchdowns on Tornadohunter live stream in southern SK..

    http://live.tvnweather.com/#

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  75. Rob,

    question...

    Do you think that the severe weather in SSK will become a squall line tonight and move through the province overnight into tomorrow morning with possible strong winds and hail or are we looking at a decaying MCS?

    And is there any chance of severe weather later tomorrow here in the RRV or will it be mainly SE MB and NW ONT?

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  76. Another nice event in Saskatchewan. The rich get richer. They are west of the main ridge and reaping the rewards.

    NAM and other models do show elevated convection affecting parts of southern Manitoba tomorrow morning, maybe into the early afternoon hours. By the time surface based stuff fires, the front will likely be off to the east.

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  77. Yes, I think it will turn into a squall line which will continue to push eastward across eastern SK tonight into SW MB overnight and Wed am. I think however that it will be losing steam by the time it reaches us here in the RRV by midday Wed.. Any further development tomorrow will be mainly east of us along the Ontario border into NW Ontario as well as nrn MN..

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  78. Models increasingly agree on stalling this system out over SW MB / the western escarpment of the RRV. Might give a little bit of time for things to cook a little further east in the morning...

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  79. Wow..just looking at the lawns across the city and they are not very green..drying out...suddenly when it looked we getting out of the drought back in may we are slipping back into it..Been very dry and hot of late.

    Rob, are there indications that this hot and dry weather will continue at least over the next 2 weeks?

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  80. Anonymous.. Long range guidance and CPC outlooks point to an upper ridge building over the western Prairies later this week into the weekend, which would tend to give us warmer and drier than normal weather over southern MB over the next week or two. That'll probably mean more brown lawns, but I actually don't mind the reprieve from mowing the lawn every 3 days!

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  81. Rob,

    Could that mean we could be getting into some of that USA heat with that upper ridge building in?

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  82. Saw some CG flashes of lightning while heading back home. Stay safe!

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  83. Insofar as brown lawns - it doesn't take rocket science to know that you don't cut your lawn short during hot dry weather. Forget what your neighbour is doing - leave it long during any hot spell and cut (or better yet mulch) once the heat breaks. If this means no cutting for a month that is not a problem even for an electric mower. Always always always cut/mulch long (3") during July & August.

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  84. SW MB hit hard overnight with some strong storms... 78 mm of rain in Boissevain with a gust to 91 kmh between 6-7 am. 30-50 mm rainfall amounts common over the far southwest. We're finally getting some rain here as well, but not as heavy as to our southwest. Still, there are some stronger cells to our west that may give Winnipeg some heavy downpours later this morning.

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  85. Some of the more impressive rain totals from the CWB Weatherfarm mesonet over SW MB.. Turtle Mtn area really hit hard.

    Boissevain.... 102 mm
    Dunrea ....... 91 mm
    Killarney .... 83 mm
    Minto ........ 69 mm
    Elgin ........ 69 mm

    Peak wind gusts of 50-90 km/h, with peak rainfall rates of 125-250 mm/hr. Impressive.

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  86. July 4 of last year was the only thunderstorm we had until August 18. Hopefully this year July 4 wont curse us again.

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  87. Lightning in the Altona area this morning has been nothing short of incredible. Frequent cloud to ground strikes. Severe stuff remained just south of the border.

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