Friday morning's significant rain event

We woke up to a significant rain event Friday morning with 35.4 mm coming down between 7:45 am and 8:15 am. This translates to a 1 in 10 year precipitation event.

Although that was definitely the peak of the event, between 7 and 9 am we got around 50 mm.

One factor that probably intensified the runoff was that we had received about 10 mm of rain overnight making the ground just that much more saturated. Thus the rain that hit in the morning was more likely to run directly off into the river systems instead of percolating into the ground.

To show how localized the storm was the Grand River rain gauge in Brantford only recorded about 4 mm of precipitation this morning.

Here are some pictures of the Silver Lake at around 11 am this morning:






You can contrast the water level will the even larger storm we had back in July of 2008:

http://uwweatherstation.blogspot.com/2008/07/record-rainfall.html