August 1, 2014

[WayfaringStranger]

Severe thunderstorm warning in effect for:

Newmarket - Georgina - Northern York Region- Uxbridge - Beaverton - Northern Durham Region - Lindsay -
Southern Kawartha Lakes - Peterborough City - Lakefield - Southern Peterborough County - Innisfil - New Tecumseth - Angus
Orangeville - Grand Valley - Southern Dufferin County - Shelburne - Mansfield - Northern Dufferin County - Mount Forest - Arthur -
Northern Wellington County - Hanover - Dundalk - Southern Grey County

Updated or ended by 5:41 p.m. EDT.

At 2:42 p.m. EDT, Environment Canada meteorologists are tracking a severe thunderstorm capable of producing very strong wind gusts, dime to nickel size hail and torrential rain.

Take cover immediately, if threatening weather approaches. Fast moving water across a road can sweep a vehicle away. Large hail can damage property and cause injury. 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 or tweet with the hashtag #ONStorm.

For more information:
http://www.emergencymanagementontari...eprepared.html.

[Stormydude]

There's quite a lot of rotation on the storm moving just north of Oshawa. EC should really put a warning up on that storm.

http://radar.weather.gov/radar.php?r...01111&loop=yes Here's NWS Buffalo radar.

[tice23]

two cells to watch right now are the one between keswick and newmarket, and the one south of port perry.

first one has decent rotation through the lower levels, but nothing to crazy yet, the port perry storm is showing defined rotation through the upper levels but nothing major at the surface yet, both cells have potential though.

beat me to the post stormy dude, lol. but yes i defintely see it


[edit]
I took a screen cap of the 1.50 deg from king city, you can really see it there, but the 0 deg scan is still muddled

port perry by kevintheiss, on Flickr

[tice23]

another cell to watch is developing north of strathroy, it also has some rotation, 24,000ft top

[DarkSky]

Summary:

656 
AWCN11 CWTO 021008
UPDATED WEATHER SUMMARY FOR SOUTHERN ONTARIO AND THE
NATIONAL CAPITAL REGION ISSUED BY ENVIRONMENT CANADA
AT 6:08 A.M. EDT SATURDAY 2 AUGUST 2014.

THUNDERSTORMS DEVELOPED SUDDENLY FRIDAY AFTERNOON IN AN INCREASINGLY
WARM, HUMID AND UNSTABLE AIR MASS THAT WAS OVER SOUTHERN ONTARIO.
THERE WERE A FEW REPORTS OF PEA TO MARBLE SIZED HAIL, TORRENTIAL
DOWNPOURS AND FREQUENT LIGHTNING FROM THE THUNDERSTORMS. THIS IS AN
INTERESTING CASE WHICH SHOWS HUGE VARIATIONS OF RAINFALL AMOUNTS
ACROSS THE REGIONS. WHILE AREAS NEAR LAKE ERIE AND GEORGIAN
BAY ESCAPED WITH NO RAIN AT ALL, MANY LOCALES EXTENDING FROM NEAR
SARNIA ACROSS WATERLOO REGION TO NORTHERN PARTS OF THE GREATER
TORONTO AREA WERE SOAKED WITH 10 TO 25 MM OF RAIN ACCORDING TO
WEATHER RADAR ESTIMATES. RAINFALL AMOUNTS OF 25 MM OR MORE WERE
RECORDED IN A FEW LOCALITIES, AS SHOWN IN THE TABLES BELOW.


THE FOLLOWING IS A SUMMARY OF WEATHER EVENT INFORMATION RECEIVED BY
ENVIRONMENT CANADA AS OF 12.00 MIDNIGHT EDT.

LOCATION                     EVENT
BUTTONVILLE AIRPORT          27.8 MILLIMETRES OF RAIN
UXBRIDGE                     28.6 MILLIMETRES OF RAIN
COOKSTOWN                    PING PONG BALL SIZED HAIL

THE FOLLOWING ARE COURTESY OF THE GRAND RIVER CONSERVATION AUTHORITY

LOCATION             TOTAL RAINFALL AMOUNT IN MILLIMETRES
DUNDALK                      42.0
WELLESLEY                    31.6
NEW HAMBURG                  38.0

THE FOLLOWING ARE COURTESY OF TORONTO REGION CONSERVATION AUTHORITY

LOCATION             TOTAL RAINFALL AMOUNT IN MILLIMETRES
G ROSS LORD DAM              70.4
MILNE DAM                    55.8


PLEASE NOTE THAT THIS SUMMARY MAY CONTAIN PRELIMINARY OR UNOFFICIAL
INFORMATION AND DOES NOT CONSTITUTE A COMPLETE OR FINAL REPORT.