Tuesday, July 25, 2017

Seasonably warm weather to close out July.. but 30C heat continues to elude Winnipeg

It will be a nice warm week ahead with high temperatures generally in the mid to upper 20s over the RRV and southern MB. Conditions should be generally dry as well with little in the way of showers or thunderstorms expected through Friday. The next threat for organized showers will be on Saturday as a weak frontal system slides through southern MB. The greatest heat through the end of the month however will still be focused out west over SK and AB which have experienced multiple days of 30C or more this month. In Winnipeg, we have yet to hit the 30C mark in July, even though precipitation has been below average and sunshine has been plentiful. The upper pattern this month has brought the bulk of the heat over western Canada with cooler temperatures over eastern Manitoba into Ontario.  There is a chance Winnipeg may be close to the 30C mark by the end of the week. Since 1872, there have been 12 Julys in Winnipeg that have failed to reach the 30C mark, most recently in 2009. With one week to go, we'll see if July 2017 is added to that list.

50 comments:

  1. Rob is july going to finish top 30 coldest? What's the monthly mean right now? I'm not sure if the EC listing is accurate because of the missing data.

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  2. July average through the 24th is around 18.5C (those 3 missing days won't affect the average much) For us to finish with a top 30 coolest July, we'd have to finish with an average below 18.5C. With generally warm weather through the rest of the month (daily mean around 20C) it's unlikely we'll have a top 30 coolest July. Which is OK by me!

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    1. Aww I thought we might as well get a top 30 coldest considering it's been kind of miserable anyway.

      Are we looking at the potential for a top 30 coldest summer? It certainly feels like it should be.

      Even though july likely won't be a 30 coldest, it will finish below average, which will mark the third consecutive month below the mean average. A new streak? I hope so! And I hope it'll continue into the fall and winter as I want a classic old fashioned winter this year. Although I agree a couple of 30C days in there would be nice for August.

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    2. I don't think too many people would describe this month as "miserable". It's actually been quite pleasant with lots of sunny days, comfortable temps and humidity, adequate rain (mostly at night too) and no mosquitoes! It's been a terrific month for outdoor activities. I think most people would think this was a perfect summer month, despite the lack of 30C heat.

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    3. Yeah idk. I just feel it hasn't been the greatest summer month. I mean as you can tell I like cold weather but honestly I would like to have some good summer heat before the season is done. I'm longing for a couple of 33C+ days.

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  3. Rob, what are your thoughts regarding storm threat for Saturday? Are severe storms possible in Southern Manitoba/RRV?

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    1. Slight risk of some storms popping up Saturday afternoon/eve ahead of a weak frontal trough pushing across southern MB. But dynamics look weak, as well as wind shear. So a few cells may pop up Saturday, but the severe threat looks low at this point.

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  4. Medicine Hat AB hit 33C today, their 17th day of 30C or more this month. And it looks like they'll be 30C or more the rest of the month, so they'll end up with 22 days of 30C or more in July. Quite impressive, but they've had more. 3 July's had 27 days of 30C or more, namely 1936, 1917 and 1914. 2 others had 24. 22 would tie 1926 as the 6th most 30C days in a month in Medicine Hat. But Medicine Hat is no stranger to 30C heat in July. They average about 11-12 30C days every July.

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    1. Medicine Hat is forecast to reach 37C today. And its seven-day outlook has highs fluctuating between 32C and 37C. Its humidex tends to be next-to-nothing too.

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    2. Rob why do they get so much hotter than us being at the same latitude as well? Aren't their winters warmer too?

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    3. Southern AB is warmer than southern MB due to the influence of the Rocky Mountains, as well as its drier climate. Areas east of the Rockies often get chinook warming with air coming down the eastern slopes of the Rockies, which can warm them up considerably, especially in the winter. In the summer, they can get hotter temperatures due to the extreme dryness over southern and southeast AB, which allows air to heat up more efficiently than air with more moisture (as we have here) Also they have no large moisture sources (eg lakes, forests, etc) which can help to modify hot airmasses. So their climate is more desert like than ours, even though they are at the same latitude as us.

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    4. Thanks rob. So basically our climate is colder because we don't get the influence of the Rockies? I've heard of Alberta getting up to 20C in January while it struggles to exceed freezing for the entire period of DJF here. In southern Alberta do they have snow on the ground all winter like we do given the fact that they get those warm ups?

      I think we could hit 30C today. What do you think?

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  5. Given the forecast I think we will get a 30C this month.

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    1. If we don't hit 30C tomorrow (Friday) then we should do it Saturday for sure. But I think we have a good shot at it tomorrow. Note that Saturday may see some late afternoon tstorm activity.. not currently reflected in the sunny forecast.

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    2. I suspect we will reach 30C today

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    3. A high of 28.7C at YWG airport today, but it did hit 30.1C at the Forks. 30.3C at my backyard station. Most places in Manitoba hit 30C or higher today except the far north and near the big lakes. Winnipeg airport was one of the lower readings in southern MB today.. not sure why that would be.

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    4. The airport is always colder it seems. I wonder if we will get a 30C in the last 3 days of this month.

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    5. Would like to see an analysis in the occurrence of >= 30 C temperatures since the station was moved the last time. Calibration or site may be an issue.

      The fact that the recording station is continually being moved to colder and colder location (further out to the NW and more affected by cold drainage flows possibly following the Omand's creek basin) needs to be taken into account when doing any sort of trend analysis. Would be a great way of obfuscating evidence of global warming wouldn't it?

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    6. Why would they be moving it to colder locations?

      Despite the fact it's sitting in a relatively cold location we have seen a huge clustering of record warm years since 2000. I actually think it's important to have the recording station in a cool airport location because it gives an idea of what the temperature should be without the urban heat island effect. If we recorded from say the forks than it would skew everything and all the old records would be worthless.

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    7. The station has been moved multiple times including as recently as a few years ago (after 2000). No idea what the reasons for the moves were. The effect in question is different from a typical lack of urban heating.. there is an issue with cold drainage affecting the station during night time (especially with snowcover). It is not uncommon in some situations for the airport to get colder than surrounding Manitoba-Ag stations (situated in rural areas).

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  6. EC is predicting only 27C for Saturday?? Seems odd given the other forecasts that are out there. I thought we'd hit 30 today but I guess not

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  7. Well no 30C once again today for YWG Airport. In fact temps have taken a nosedive in the last while. Down to 23C as of 3 PM behind the cold front and weak showers that are passing through. Thunderstorm threat has pretty much diminished for the Winnipeg area at this point. Cold front is producing some storms well west and southwest of here but nothing severe as of yet. Best chance for severe weather now is well south of Winnipeg along the US border.

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    1. Another bust.... as usual. No storms for us. I thought for sure we would make 30C today....

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  8. Winnipeg Airport reporting a reading of 30.2C as of 3PM. Rob's Obs reporting 31.3C. Looks like it won't be a 30C free July after all.

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    1. Official high of 31.0C at YWG airport today, and 32.1C at the Forks (as well as my site). Felt much hotter with that blazing sunshine, light wind, and high dewpoints. Scorcher! But not as hot as southern SK today. Up to 38C (actual temp) in Regina and Moose Jaw!

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    2. Yes it was certainly a hot day! I saw the 38C temps in southern SK on EC's website. Pretty amazing! Do you think we will hit 30C again today?

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  9. Another bust for Winnipeg! Windy, hot conditions causing rapid drying today. Will be the third consecutive month of below normal precipitation.. and its starting to add up. Hopefully some rain as the cooler air moves in the next few days.

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    1. I wish we'd just get some good storms for once. Humidex of 40 and we can't even get a drop of rain or rumble of thunder. I hope the dry pattern doesn't continue into fall and winter.

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  10. July 2017 will tie for 26th least 30C days since 1872 ( 2 days )

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  11. July finished with a mean of 19.3C according to EC's records. This mean is 0.3C below the average which marks our third month in a row of slightly below normal temperatures.

    So since July had those 3 missing days of data in environment Canada's logs, do they never actually record the months mean temperature? Do they have the actual highs for those days in their records and it's just not showing on the public section or do they really not have them?

    What kind of records does EC keep and why aren't they readily available to the public? I'm grateful for the weather records website by JJ. It got restored in June and it's updated and better now. It's the website I check every time I want to see a record. Does EC keep track of these records and just not show them to the public?

    Apparently they don't track low maximums or high minimums which I think is odd. As our federal weather service they should be keeping track of all the records. JJ's weather books are easily the most comprehensive and complete records database for winnipeg available anywhere.

    The NWS in the USA keeps track of records and publicly displays them so why cant EC sort out their ridiculous mess. They provide 1938-2008 data to the media which is grossly inaccurate especially considering winnipeg had good climate records all the way back to 1872, I don't understand why EC doesn't utilize this.

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    1. Matthew.. Eventually, those missing records should be added to the database at some point, but it may take awhile. The problem with EC climate data input right now is that a lot of it is automated with crude quality control checking. If there's missing data, it will stay as missing until they are informed of the missing data and it can be added manually. A lot of this data input and QC used to be done right here in Winnipeg and things got done a lot quicker, but now climate services are done out of Toronto, and it can take awhile to correct (if it ever does)

      As for the records database, EC is working on a database that merges climate records for a particular site together to span a longer timeframe and incorporate different stations in the same general area. Thus, Winnipeg would get a merged database from 1872 to the present using records from St John's College to the current airport site (which is what JJ does for his records database). There are some issues with it which they're trying to sort out, but a beta version is being tested. Hopefully something comes out of it soon. I agree that EC's records database is a mess right now, and frequently advertises "records" for a ridiculously short time frame. As you say, we're very lucky to have a site like JJ's here in Winnipeg that continually updates the Winnipeg records database with up-to-date and accurate stats.

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    2. Yes I am very grateful for the JJ site. I hope EC figures out their records situation because we should have had the merged 1872-2017 database a long time ago.

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    3. Correction: According to JJ July actually averaged 19.1C, not 19.3C as I stated earlier. EC's data must be wrong because of the missing value.

      So far if you put together June, July, and augusts mean so far we get 17.4C, which is tied 28th coldest summer since 1872. Considering it's only the third day of August though this mean will likely warm and probably won't be a top 30 coldest summer unless the last half of August is very chilly.

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  12. ..And no rain for today. Things will continue getting drier even as we experience cooler conditions.

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    1. Yep unfortunately we missed out on the rain yet again.

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  13. Days are starting to get noticeably shorter now... even the tree across the street is starting to drop a couple of leaves now. A sure sign that fall is on the way, despite the fact it's only early August. And with no major heat in the forecast through at least mid month, could we be looking at an early start to fall?

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  14. Rob I notice that the Weather Underground reporting for your station and all others has an unusual forecast for today. The written forecast on the WU app calls for much warmer today than yesterday in "forecast on Demand" mode and much cooler than yesterday in the "NWS" mode. In east StPaul The wind direction and speed change as well. Is this a contrarian view or a program error?

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    1. The WU forecast is an automated forecast based on weather data from the local site.. Not sure what their algorithm is, but I suspect it compares temps from 24 hrs ago to help with the next days forecast. In this case, it was a much cooler start yesterday than today which may explain the "much warmer forecast" for today. Obviously, there's more to consider but that may be one variable throwing the forecast off.

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  15. Rob. What is going on with EC's August monthly summary so far? Most days are blank and many of the few that are there have missing values. It's kind of frustrating because there's no way to tell what the mean temperature of the month is now. I can't believe we can't even rely on our federal weather service.

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    1. There were problems with the data coming from the airport weather station over the long August weekend that didn't get fixed until after the holidays. As a result there are several days of missing data over that time. At some point, the missing data will need to be updated with "estimated" data for those days, but I don't know when that will happen.

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    2. Thanks rob. But the station itself was reporting data and taking measurements the entire time as the environment Canada website was working. So how come they don't have the data?

      So do we have no idea how the month is turning out? We'll need data to determine where the summer ranks.

      Sometimes I think the old fashioned mercury thermometer was better lol.

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  16. Intensifying drought conditions locally with Rob's site only recording 5 mm half way into August. Persistent Rex block pattern with upper and surface high pressure over Manitoba undercut by 'troughiness' over the Central and Northern Plains. Multiple weather systems have split apart or skirted around the province - with models suggesting a repeat for Tuesday/Wednesday system.

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    1. We've had some very chilly nights. This blocking pattern seems to be bringing hot days but cold nights. Normally we don't get cold at night like this until a couple weeks after now.

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  17. Rob will there be enough rain tomorrow to seriously dampen da drought (pun intended) trees in south central St Vital are showing the effects
    . Without immediate and substantial rain they will not be with us in mid late October as They were last year.

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  18. Area of showers and embedded t-showers has developed over central N Dakota towards S Manitoba associated with weak LLJ and PWATs of 40 mm. Mean flow would advect these towards Winnipeg *if* forcing holds up. 12Z runs of NSSL 1 km WRF showing potential for heaviest accumulations in N Dakota (25-50 mm) but suggest 15-25 mm for our region - which would be very welcome. Leading edge would arrive in the next few hours, but precipitation is light and may dry up. Bulk of heaviest rain would occur 12-6 am.

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    1. Pretty good validation from the model.. although QPF is slightly overdone. Radar estimates from Bismarck and NDAWN stations suggest a corridor of about 20-30 mm of accumulated precipitation thus far under region of convection.

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    2. NDAWN stations in N Dakota show a corridor of 30-50 mm QPE from west of Bismarck to Devil's Lake. Unfortunately amounts drop off drastically near the Manitoba border. Around 5 mm locally, with monthly total rain only around 10-15 mm for the city. The drought continues..

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  19. I don't know how much rain we will get but we could certainly use some.

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  20. Drought conditions will be exacerbated considerably tomorrow with desiccating conditions projected.. there will also be wild fire concerns.

    Strong SSW flow of 40 km/h indicated from high resolution model guidance. Need a SSE trajectory for enhanced wind speed from funneling effect up the RRV, but SW component will help facilitate mixing and reduce dewpoints and RH. Some uncertainty as to moisture return and evapotranspiration (from areas of N Dakota that have received up to 125 mm of rain this month).

    This will also affect convective potential tomorrow evening as cold front moves in. Depending on the moisture available.. 1000 to 1500 J/kg CAPE will be present. Cap will have to be overcome - and given previous similar cases - there will likely be isolated to scattered cells forming by early evening in areas of better mesoscale forcing (around lakes, sloping terrain, etc). Not looking good for much rain in Winnipeg.

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