Canada Day Severe Weather (July 1)

[Mesocyclone97]

Surprised no one posted about tomorrow yet so thought I would start the thread. Looks like my area (GTA) will miss the most intense action, which is slated to occur farther east . An interesting MCS (Derecho) is currently east of Michigan, and is on track for Southern Ontario, though....

[Stormydude]

Aaaaaaand the derecho is gone. I predict that Windsor will get the start of a line of severe storms around mid morning. This line will push through London with damaging winds, and proceed to appear like it will slam into Kitchener. Then the line will break up just enough to give some light rain and quiet thunder before reforming before it reaches Toronto and Hamilton by mid afternoon. Meanwhile, north of the line, two supercells will form, spawning two EF1 and an EF2 tornado somewhere between Barrie and Peterborough. These cells will be met up with another strong line which will race through Eastern Ontario for the late afternoon and continue through Southern Quebec through the evening. All severe weather will end by 1am July 2nd.

Now and to wait and see how much of this will happen!

[tice23]

This has been a tricky one predict.

here are my thoughts:

As it crossed Michigan its direction has been mostly eastward, the new cells are now tracking north east bringing that segment across southern ontario. there is plenty of CAPE to continue fueling the system as well as high levels of shear particularly closer to 6-11am period which hopefully will sustain the system and new cells to the north east as it comes through. i think the most intense weather from this first system will track from sarnia at 4am to orillia at 10am covering most of southern ontario with its swath. particular caution for tornadic storms from goderich to new tecumseth starting at 6am.

in the afternoon i see the second line bringing more storms to the same regions, perhaps extending more southerly, and the northern portion of this storm intensifying from muskoka to sudbury with elevated tornadic potential around parrysound around 3pm,

That's my guess anyway.

[tice23]

Also, warnings and watches have been up for some time, i'm going to bed, and hopefully there will be some storms to chase when i wake up.

2:57 AM EDT Tuesday 01 July 2014
Severe thunderstorm warning in effect for:

    Sarnia - Petrolia - Western Lambton County

Updated or ended by 4:30 a.m. EDT.

At 2:57 a.m. EDT, Environment Canada meteorologists are tracking a line of severe thunderstorms capable of producing very strong wind gusts, dime to nickel size hail and heavy rain.

The strongest storms will affect the regions between 3:00 AM and 4:30 AM.

Take cover immediately, if threatening weather approaches. Fast moving water across a road can sweep a vehicle away. Strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles. Remember, severe thunderstorms can produce tornadoes. Go indoors and move away from windows and skylights. Avoid areas of the building that could be affected by falling debris such as tree limbs. Avoid driving through water on roads. Watch for possible washouts near rivers, creeks and culverts. In Canada, lightning kills up to 10 people every year. Remember, when thunder roars, go indoors.

Emergency Management Ontario recommends that you take cover immediately, if threatening weather approaches.

Environment Canada meteorologists will update alerts as required, so stay tuned to your local media or Weatheradio. Email reports of severe weather to storm.ontario@ec.gc.ca or tweet with the hashtag #ONStorm.

For more information:
http://www.emergencymanagementontario.ca/english/beprepared/beprepared.html.

[tice23]

well that was a lot less exciting than i had hoped :/

[Stormydude]

I was right about it breaking up before reaching Kitchener, otherwise, I've been totally wrong so far!

[Mesocyclone97]

Looks like nothing much is developing, guess that decaying MCS that went through really modified the atmosphere ahead of the front and took out a lot of the energy from the atmosphere. At least we have a safer Canada Day then, I guess?

[Raedwulf]

Bit of an iffy start for southern ontario for a storm season..I've said it again and again over the past few years..hard to top 2006 and 2009..everything else sort of seems lack luster...fingers crossed we get some beautiful structures this year..but don't want to get my hopes up.

[tice23]

I would like to learn what kept systems like this one from exploding, theres atleast a handful every year that look like they have all the right ingredients, then poof, they fall flat. EC seemed to be spot on with their watches and warnings this time around by not over extending the regions, but what did they see?.....

[justinb]

Originally Posted by tice23

I would like to learn what kept systems like this one from exploding, theres atleast a handful every year that look like they have all the right ingredients, then poof, they fall flat. EC seemed to be spot on with their watches and warnings this time around by not over extending the regions, but what did they see?.....

Apparently it was the decaying overnight/early morning MCS and associated convective debris and outflow boundaries that came through the regions. It caused significant convective overturning which killed the instability. NWS SPC and Environment Canada knew in advance from experience that this would cause significant uncertainty and that modelling would not pick up on this primarily due to limited resolution. Having said that there are times when this is expected to occur yet severe storms break out regardless.