This map (click on the picture to see a larger version), which I found on the Agriculture Canada site shows the areas of extreme dryness for this season in southern Ontario.
We are located to the right of London near the tip of Lake Ontario where the yellow (low) and orange (very low) regions converge. The long range forecast shows that there may be a chance of rain on June 24. That would make it roughly a month since the last decent rain, which brought only 2/3 of an inch.
I ran sprinklers this morning and evening and so far I've used up 2/3 of the water from the water truck, which delivers about 40,000 gallons to the cistern. The gardens that I watered are looking very grateful indeed, as it got up to 32C today (almost 90F).
I have to admit that in spite of all my grumbling about the weather and no rain, the garden looks wonderful early in the morning and positively magical in the evening. I must sit out more, and get away from the computer and the hoses. Don't ya love summer?