I haven’t had any reports of ice in two days, and although the satellite images are not crisp, there’s no sign of ice anywhere near where it was last seen. I’m pretty sure the last of it is gone.
The only question in my mind is whether to say our ice-out date was yesterday or today. I’m leaning towards yesterday, May 13th.
You might be wondering how accurate our predictions were. I looked them up for you, and I’ll summarize them here. I’ll include both the first estimate from early April and the revised estimate in late April when we learned there was a winter storm coming.
I work in five day periods because, like this year, we don’t always know the exact date the last speck of ice melted. Sean Cockrem and Stu Everett picked specific dates, but I’ll spot them two days leeway either side to make it fair.
I work from aerial photos and satellite images. In early April, there wasn’t much open water to judge by, so I made my first guess a very vague one, based on reports of thinner ice than usual. I initially said I thought we’d be ice free in the first ten days of May. That was off, and on April 20, when the winter storm was imminent (and we had more meaningful aerial photos and satellite images) I revised it to May 11-15. That worked out to be a good guess.
Sean Cockrem uses winter temperature records and spring forecasts. As the spring weather unfolds, he replaces forecast temperatures with actual ones, and revises his graphs. His first graph called for us to hit his proposed thaw index on May 10. Two days grace puts him covering anywhere from May 8 to May 12, so his first estimate was pretty close. He waited until April 28 to factor in the unexpectedly bad weather, and revised his estimate to May 14, giving him a May 12 to May 16 bracket, and bang on.
Stu Everett goes by snow cover. He’s been watching the thaw for a long time, and he goes by the average time-span from when the snow melts to when the ice melts. He initially predicted May 10, so we’ll expand that to May 8 to May 12 to give him the same margin of error as Sean and I. That didn’t quite work out, and that late April snowstorm threw a serious wrench in his calculations by giving us days more with snow cover. He revised his estimate to May 15. So I’ll expand that to May 13 to 17, and he got a hit, too.
So in summary, once the thaw is well underway, we all managed to make a reasonable estimate two or three weeks in advance. Our predictions five or six weeks in advance were less accurate, of course.
So thanks for tuning in, and even warmer thanks to everyone who sent photos, submitted reports, made comments, or asked insightful questions. The true strength of Ice Patrol comes from pooling our knowledge.
Ice Patrol will now wind down for another season. I’m still hoping for a good satellite shot of Lake of the Woods, and I’m keeping an eye out for one of the Red Lake/Trout Lake area, too.
Oh, let’s finish with a photo that Guy Belluz submitted as a sign of spring.
He found a painted turtle hatchling near the water’s edge in the French Narrows area. He made sure it got to the water.