Jun.23, 2010 - SPECIAL WEATHER STATEMENT

[DarkSky]

162 
 WOCN11 CWTO 231458
 SPECIAL WEATHER STATEMENT
 ISSUED BY ENVIRONMENT CANADA ONTARIO REGION.  10:58 AM EDT WEDNESDAY
 23 JUNE 2010.

SPECIAL WEATHER STATEMENT ISSUED FOR..
 CITY OF TORONTO
 WINDSOR - ESSEX - CHATHAM-KENT
 SARNIA - LAMBTON
 ELGIN
 LONDON - MIDDLESEX
 SIMCOE - DELHI - NORFOLK
 DUNNVILLE - CALEDONIA - HALDIMAND
 OXFORD - BRANT
 NIAGARA
 CITY OF HAMILTON
 HALTON - PEEL
 YORK - DURHAM
 HURON - PERTH
 WATERLOO - WELLINGTON
 DUFFERIN - INNISFIL
 GREY - BRUCE
 BARRIE - ORILLIA - MIDLAND
 PARRY SOUND - MUSKOKA
 HALIBURTON
 RENFREW - PEMBROKE - BARRY'S BAY
 ALGONQUIN
 BURK'S FALLS - BAYFIELD INLET.

..SEVERE THUNDERSTORMS POSSIBLE IN SOUTHWESTERN ONTARIO BEGINNING
 THIS AFTERNOON..

A COMBINATION OF A WARM..HUMID..AND VERY UNSTABLE AIRMASS AND A
 DISTURBANCE APPROACHING SOUTHERN ONTARIO MAY RESULT IN STRONG TO
 SEVERE THUNDERSTORMS ACROSS A LARGE PART OF SOUTHWESTERN ONTARIO
 LATER THIS AFTERNOON INTO THIS EVENING.  A SEVERE THUNDERSTORM WATCH
 HAS ALREADY BEEN ISSUED FOR EXTREME SOUTHWESTERN ONTARIO INCLUDING
 WINDSOR AND SARNIA.  THE MAIN SEVERE THREATS WILL BE DAMAGING WINDS
 AND HEAVY RAINFALL AMOUNTS IN EXCESS OF 50 MM.

..HEAVY RAIN MOVING IN TONIGHT FOR REGIONS FROM EAST OF GEORGIAN BAY
 TO THE UPPER OTTAWA VALLEY..

THE VERY MOIST AIRMASS COUPLED WITH AN INTENSIFYING LOW PRESSURE
 SYSTEM WILL PRODUCE LOCALLY HEAVY RAINFALL AMOUNTS OVER REGIONS FROM
 FROM EAST OF GEORGIAN BAY TO THE UPPER OTTAWA VALLEY.  THE HEAVY RAIN
 WILL BEGIN NEAR GEORGIAN BAY EARLY THIS EVENING AND SPREAD EASTWARD
 THEREAFTER.  FOR MANY LOCATIONS 20 TO 30 MM OF RAIN ARE LIKELY WITH
 LOCAL AMOUNTS UP TO 50 MM POSSIBLE WHERE ISOLATED THUNDERSTORMS
 AUGMENT THE RAINFALL TOTALS.

..HUMIDEX VALUES APPROACHING UPPER THIRTIES THIS AFTERNOON..

A WARM AND HUMID AIRMASS WILL PRODUCE HUMIDEX VALUES IN THE 35 TO 39
 DEGREE RANGE ACROSS MANY PORTIONS OF SOUTHERN ONTARIO TODAY. HOWEVER
 THESE HUMIDEX VALUES REMAIN JUST BELOW THE ADVISORY THRESHOLD OF 40.
 COOLER AND DRIER AIR RETURNS FOR THURSDAY.

END/OSPC

[Derecho]

Not as exciting as this mornings SWS about the potential for tornadoes today. They removed tornado and replaced it with heavy rains in the updated statement.

Ay-yaye-yaye.