Topic: Canadian severe weather July 18-22

[Mike]

There's some interesting weather forming in Alberta again over the next few days.  Profiles re wind shear and the like were not that strong a few days ago, but things have picked up.  With the Canadian tornado season seeming to hold momentum members might like to keep an eye on things for anything and make comments.

Here's a satpic of storm initiation for today thus far.


Mike

[Jimmy Deguara]

Hi Mike,

Do you have some satellite imagery that shows what occurred from this system and a copyright notice link to the resource?

Regards,

Jimmy Deguara

[Mike]

I shall hunt some down and post the results with copyright info to keep everyone safe.

Mike

Have found some animation and graphic of today's weather in Eastern Canada.  The animation did not stick, but the image is impressive.  CAPE values are up to 3000+ today (their time) and there's strong storm convection brewing in the NW to NE portions.  The mixing ratio model is also pretty strong. The jetstream graphic shows an enormous amount of storm activity in all areas shown by the lightning bolt icons - I can only wish....!

       * Acknowledgement to Environment Canada /GOES Eastern Canada satimage/Reed Timmer mixing ratio graphic *

[Mike in Canada]

Hi. Being a resident of Edmonton,which is pretty much in the centre of Alberta, I've noticed just how awfully humid it's been the past few days. I'm not an expert in meteorology, but I've noticed that the dewpoint in Edmonton's been up to 20°C since around noon and hasn't dropped below 16°C in the last 24 hours. It's been so humid that the air temperature hasn't dropped below 22°C in the last 24 hours and that it was still uncomfortably warm and muggy today despite mostly overcast conditions this morning and early afternoon.

Of course, this current weather pattern is highly unusual for Alberta, and I personally don't recall having seen this level of humidity during warm/hot weather here in this part of Alberta since the time of the Pine Lake Tornado in 2000 and the Edmonton Tornado in 1987.

Currently (5:00 pm MDT), the temperature is 28°C and the dewpoint 20°C, with hazy skies clearing from mostly cloudy conditions earlier in the day. And, yes, it's uncomfortable out there.

I've yet to see any big storms firing up in the foothills of the Rockies, which I find a bit strange, but a line of storms have already begun in earnest NNW of Edmonton east of Slave Lake, about 250 km NW of Edmonton and all the way into southeastern Alberta.

[Mike]

Welcome, Mike with your first post!

 Thanks for giving the information on the weather there.  I hear that today and tomorrow in Alberta is definitely ripe for supercells and possible tornadoes if the conditions persist.  You'll find that the area you mentioned is quite good for severe weather formation due to the lanscape there. 

To the NW/NE of Canada is your own 'tornado alley' zone and certainly this year you've experienced some severe weather.  Looking at the radar from Edmonton last night there were large storms brewing on all sides of you, NW, N, NE and E, so I'm not surprised things are looking good.

 If you could keep everyone updated on what you are observing that would be fantastic for all members - if you get photos of the storms that would be a bonus, Mike!

regards, Mike

[Mike]

Here's some sat pics 20/7/2007 of water vapour and cloud cover from the Canada area, includes most of US also.  Strong chance of severe storms still eventuating in eastern and southern Alberta. Some supercell activity was observed in Edmonton but they did not last that long.  Areas mentioned above in areas of Alberta still show signs of good supercell formation.

Have included some satpics from 12:15 Goes satellite * courtesy of the College of Depage Weather site.

[Mike in Canada]

Thanks, Mike.

Thing is, no thunderstorms really came over Edmonton yesterday or last night, though I did see some of those huge thunderheads to the east. Though it cleared up to mostly blue skies by evening, it still remained warm and humid well into the night. However, the overnight low managed to go down lower - down to 16°C, and this morning is not as terribly humid as it was the day before. Today dawned absolutely clear, but now high cirrus clouds are already starting to come in.

As of noon today, it's 24°C and the dewpoint only 10°C and the RH 41%, with some breezes from the south at 11 km/h - more normal (and comfortable) summer conditions for Edmonton. Thunderstorms might start cropping up in the foothills later this afternoon, but because there's increasing cloud cover in the foothills and central Alberta, and with conditions being less humid now, I'm not holding my breath..In fact, there are currently no severe thunderstorm watches or warnings anywhere in Alberta, though southern Saskatchewan has had severe t-storms this morning.

[Mike]

Thanks for that.  I should have corrected the original post to not say 'in Edmonton' and from viewing the radar image at the time Edmonton and Calgary was spared the storm activity but outer zones showed cells., pays not to assume!

 What is the cut-off month for thunderstorm activity in Alberta, Mike?

Mike

[Mike in Canada]

Thunderstorm activity will usually end around the first week of September or the last week of August in Alberta.

It's currently (12:23 pm) 24°C, with a dewpoint of 10°C and sunny skies with a few cirrus clouds. Nice and dry. Thunderstorms do not seem to be in the forecast for the next couple of days, but you never know.