Monday, August 01, 2011

Winnipeg sets mark for driest July on record..

The hot and dry weather of the past month has resulted in the driest July on record in Winnipeg since records began almost 140 years ago in 1872. Only 10.0 mm of rain was recorded at Winnipeg airport in July 2011, beating the previous driest July of 2006 at 10.5 mm. Normal July rainfall in Winnipeg is around 70 mm so rainfall this month was a meager 14% of normal. Rainfall was a little higher in other parts of the city in July including downtown (17.8 mm at the Forks) and northern sections (20-25 mm over North Kildonan/E St Paul areas) due to locally heavier showers and thunderstorms earlier in the month. But southern and western parts of the city have been the driest with only 8-10 mm recorded in July along the south perimeter.

The dry weather has been the result of a split in weather systems across the RRV this past month, with the jet stream bringing synoptic systems and significant rainfall across the central Prairies, while scattered thunderstorms further south have been tracking mainly south and west of the RRV through Saskatchewan into the Dakotas (see Prairie precip anomaly map above). The result has been a lack of precipitation events especially over the northern RRV, Steinbach and the Whiteshell areas. This is in sharp contrast to the start of the growing season that saw cool and wet conditions through May and early June across the region. The dry weather now has become a serious concern for farmers whose crops have not developed deep enough root systems to tap into more plentiful soil moisture deeper down in the earth.

The southern Red River valley was not quite as dry in July, being grazed by some thunderstorm complexes tracking through North Dakota. Areas from Morris to Emerson saw around 50 mm in July, while heavier amounts were recorded south of the border including Grand Forks at 67 mm, and Fargo at 133 mm.

Some July rainfall totals included..

Winnipeg airport..... 10.0 mm
Winnipeg Forks ...... 17.8 mm
Charleswood ........... 14.0 mm /Rob's Obs/
Brady landfill ........... 9 mm
Oak Bluff ................. 9 mm
St Vital .................. 14 mm
Whyte Ridge ............ 20 mm
N. Kildonan .............. 20 mm
E St Paul .................. 24 mm

Starbuck .................. 8 mm
Steinbach ................. 9 mm
Sanford .................... 10 mm
Portage ................... 14 mm
Pinawa .................... 16 mm
Selkirk ..................... 17 mm
St Pierre ................... 26 mm
Winkler .................... 35 mm
Carman ................... 38 mm
Morden ................... 44 mm
Morris ...................... 47 mm
Emerson ................... 55 mm
Grand Forks ............ 67 mm
Fargo ........................ 133 mm

Gimli ......................... 70 mm
Arborg ..................... 57 mm
Brandon .................. 65 mm
Dauphin .................. 153 mm
The Pas .................. 141 mm

7 comments:

  1. This is what everybody wanted, right?

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  2. Not everyone.. many of us want thunderstorms. On a purely selfish level, I'm enjoying this weather.. but I concede that we really need some rain.

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  3. BTW, Rob's Obs still not updating due to FTP problems with SHAW. Hopefully I can get it sorted out soon..

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  4. Rob is this the third consecutive year for this no updating at end of July??

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  5. Jim..I think it was early July last year or the year before.. but yes, it does seem to occur around this time. And of course, I can't get SHAW support because of long holiday weekend..

    I can manually FTP the images to my website.. but I have better things to do than FTP computer files every 5 minutes!

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  6. Well I think I've solved the problem.. an upload folder was mysteriously renamed and was causing FTP errors. Not sure how that happened as I never change that folder specification. Never know when those computer gremlins will strike. Hopefully that does the trick..

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  7. Nice site!! Great info, I am always very interested in weather facts and figures!! Cheers!!

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