Grey Bruce has gotten almost a full month’s worth of rain in the first ten days of the month.
“Certainly it’s more than just anecdotal, people feeling there’s been a notable amount of rainfall, we can just see it in the daily observations from the Wiarton airport. The last six days solid has seen notable amounts of precipitation,” says Environment Canada Warning Preparedness Meteorologist Geoff Coulson.
He explains, “The Wiarton airport has already received 97.2 mm of rain so far this month, and in terms of looking at the long-term average rainfall for the whole month of October, it’s actually the same value, 97.2 mm, so we’ve received about an average month’s worth of rain for the area and we’re only about a third of the way through the month.”
Coulson adds, “It’s a significantly wetter than normal start. In terms of records, we’ve still got a ways to go to be rivaling the record for the whole month of October and that was set back in 2013 when 207 mm fell.”
He expects the region will get more rain in the coming weeks, but adds, “It’s still difficult to say whether that record is going to be at risk or not.”
Coulson also says Tobermory had similar numbers to Wiarton, noting, “They picked up 85 mm so far this month, so again, wetter than normal.”
He says, “It’s been a combination of a series of storm systems moving through the area, as well as fairly frequent off-lake showers. We’re getting cooler air coming down from Northwestern Ontario moving over the relatively warmer waters of Lake Huron that’s generating instability, convection clouds and shower activity and these bands of showers have locked in over the Bruce Peninsula and southern parts of Georgian Bay.”
“Today is another example of this off-lake shower activity,” says Coulson, adding, “We’re seeing on radar this cooler than normal air mass moving over Lake Superior and northern Lake Michigan, Lake Huron and then moving into the Bruce Peninsula so it’s relatively localized shower activity along the Bruce Peninsula, southern Georgian Bay area. As soon as you go much, much further north and much further south of that area, there’s really not all that much going on.”
Coulson says, “It’s the exact same mechanism that causes lake-effect snow when we get temperatures a little bit colder than this, again instability as we get colder than normal air moving over the relatively warmer waters of the lakes.”
There will likely be more rain this month, says Coulson, explaining, “We still do notice a mention of shower activity off and on over the course of the coming days. There is a large-scale storm system we’re keeping a close eye on that’s going to be coming out of Colorado in the coming days. It looks like it could bring some notable rainfall with it, but right now the models are keeping most of that rain down in southwestern Ontario, more in the Windsor and London area,” says Coulson, noting it’s possible it could reach the southern Georgian Bay area too.
He says we could see a bit of a break in the next couple of days where the showers become more spotty, adding, “Then we’ll keep a close eye out for that system on the weekend. If it stays where it is right now, most of that rain will fall south of the area.”