April 10, 2019: Falling Behind

I felt like it was time to look back and see how our current ice conditions compare to those of the last few years at this date.

As it happens, I have pictures from April 9th for 2019, 2018 and 2015. For 2016 and 2017, I have pictures from within a few days of that date. Of course, they were all taken from different heights and in different directions… but Town Island appears in each one, so I’ve marked it with a big red arrow. The arrows point roughly north, by the way.

Don’t forget: you can click on the pictures to see a full-screen, zoomable version.

Lets have a look. Here’s one of yesterday’s pictures. April 9, 2019.The low camera angle makes this picture hard to decipher, but zooming in may help. Not a whole lot of open water yet this year.

A picture taken exactly one year earlier: April 9, 2018.But cheer up, last year was worse. Look at all that strong white ice on Rat Portage Bay. Ice-out in 2018 wasn’t until May 14th, though, so doing better than that is setting the bar pretty low.

Two years ago: April 7, 2017.2017 was an early spring. The ice was all gone a couple of weeks from now. In this picture you can see that Safety Bay and Keewatin Channel are running freely, and water reaches out past Town Island towards Scotty.

Three years ago: April 13, 2016.2016 was mild, too. By the 13th of April, the water extended almost as far as 2017. Then things slowed down and we held on to some ice until early May.

Four years ago: April 9, 2015.April of 2015 had progressed more than this year, but ended up having a normal ice-out of early May.

I don’t have pictures from the right time period in 2014, and the camera I used then wasn’t as good. I can tell there was more ice at about this time than there is now. That’s cold comfort: ice-out in 2014 wasn’t until late May.

In summary, you can’t really look at one day and make an accurate prediction that spans the coming weeks. However, I will say that it no longer looks as if we have much chance of an early thaw. We’d need favourable conditions to be ice-free by early May, and the forecast doesn’t offer much hope of that.

Here’s one reason why: Stu Everett posted a comment that sheds light on how much difference snow cover makes. The short version is, it doesn’t just protect the ice from the sun’s rays. It also lowers the region’s air temperature by preventing the warming of the soil. Here’s his full explanation:


You have commented on the air temperatures in Kenora and how they seem to be holding below normal. I quote from an article I read recently: “Snow cover, or lack of it, can have a dramatic effect upon temperatures. For example when there is no snow on the ground at La Crosse, WI, the January daily average temperatures are 11.2 degrees warmer than when there is snow on ground.” OK, so let’s make that 5 degrees C.
Looks like temps will not return to normal until the ground becomes snow free. As we locals all know, there remains a fair amount of snow cover in the area, and that snow is really dense, more like ice than snow. There are still 5 cm of snow at the Kenora airport according to their data for yesterday. At the beginning of the month we had 8 cm at the airport, so the snow melt rate is really slow this year. Last year on this date there were 12 cm of snow on the ground and it took 10 days to become snow free.
So what does this mean for LOW ice out? Well I calculated last year that it is 27 days on average from no snow cover at the airport to ice out on LOW. Given the short term forecast, it seems unlikely that the airport will be snow free until this weekend at the earliest. At this time of year those 5 degrees might mean refreezing overnight, which delays melting a great deal. Last year it took some double digit temps to finally get to snow free at the airport, and that, according to the forecast seems highly unlikely in the near future. But let us be optimistic and say the airport is going to be snow free this Sunday. 27 days from Sunday is May 11. Hate to say it, but this year sure looks a lot like last year, you called ice out on the 14th, right?
One caveat though. Last year the temps got into double digits almost every day by about the 19th of April. No sign of that happening this year according to the long term forecast, sigh…..looks like another late breakup, probably after the (optimistic) May 11th cited above.
That’s pretty depressing. While I’m reluctant to forecast a late ice-out on the basis of any one single factor, we’re now looking at three unfavourable things: extensive ice, significant snow cover, and forecast cool temperatures.
My predictive method is mostly ice-based. I use comparisons like the one in this post to measure progress and gain perspective. It’s not looking great.
Stu’s preference is to look at snow cover. He’s not optimistic at all.
Sean uses mean daily temperatures: starting when that value rises above freezing, he weighs the forecast warmth against the severity of the winter. The mean temperature isn’t consistently above freezing yet, so he hasn’t even started his calculations.
Accuweather offers a forecast for all of April. That’s a long way ahead, so let’s consider it largely speculation, but they aren’t calling for double-digit temperatures until the week of the 21st.
And we’re looking at another snowfall Thursday night.
Heavy sigh.