May 12, 2018: Satellite Saturday

Ice on Lake of the Woods continues to melt away.

Devon Ostir took this picture of the last scraps of ice on the Manitou yesterday, near Wolf Island and Hare Island.

This morning he reports it is all gone.

Satellite imagery confirms that ice is vanishing. Here’s Saturday’s picture from the Aqua’s MODIS camera in true colour.

Shoal Lake has significant ice, but on Lake of the Woods, the patch south of the Barrier Islands is fading fast. The sheet of ice at the south end, near Baudette, is both bigger and whiter, but it looks very fractured, and wave action in that huge expanse of open water will probably make short work of it.

Here’s the false-colour version of the same image.

The ice actually shows less clearly in the artificially filtered scheme. Ice in the last stages of melting (see an old post about candling here) always looks the same as water in the false-colour images.

The weekend should stay sunny, breezy and warm, with temperatures at or above normal. If the remaining ice on Lake of the Woods lasts through Sunday, I expect it will vanish on Monday. I’ve already got my year-end graphs ready to go.  Shoal Lake might take a day or two longer.

 

May 8, 2018: More Good News!

I got pictures from two more co-workers. Tom Hutton and James Biesenthal were flying together, and they both took pictures.

First, the ones from Tom Hutton.

The classic Keewatin waterfront shot to get us started. No more ice in Safety Bay.

Here’s a closer look at Crowe Island, Anglican Island and Channel Island. They’re all clear, but there’s ice out past Thompson Island.

This third picture shows Gun Club Island in the left foreground, then Treaty Island and Roger’s look joined together by the low angle. That’s Town Island in the middle distance, left of center. Beyond it, by Nantons Island, there’s still ice.

Now some pictures from James Biesenthal. There’s some overlap with Tom’s pictures, but I’ve selected a few that offer a different view.

This is the Winnipeg River, looking south with Locke Bay spanning the frame in the background.

Further south, James photographed the west channel of the river, with Keewatin in the distance.

Then Darlington Bay with Keewatin in the center of the picture.

Then from over the Keewatin bridge, this shot of the cluster of islands that include Mackie’s, Cameron, Cross, Kalamalka, Gourlay and Yacht Club islands. Further right, Turnbull Island and Rheault Bay. You’d have to zoom in to see the distant ice on the Manitou.

The last shot is of Treaty Island, with Shragge’s to the right of center and Channel Island at the wingtip. More to the left are Rogers, Galt, and Town Islands. There’s still enough ice to block passage to Scotty Island, but it won’t last long.

Monday’s high was 28.3°C, but Tuesday was quite a bit cooler, reaching just 13°C. By Wednesday night, the Weather Network forecast says we’ll be dipping down to 1°C, and rising to just 9°C on Thursday. I don’t think it will matter much: for Lake Dwellers near Kenora, the lake will be navigable.

Although cool, Thursday should also be sunny, so the satellite photographs will show if there’s any ice remaining by then. Some ice may persist on the south part of the lake for a few days longer. Shoal Lake is going fast, so it might go at the same time Lake of the Woods this year.

In case you missed seeing the reports in the comments section, Clearwater Bay is open, West Hawk Lake is open, and down by Sioux Narrows,  Long Bay is open.

May 8, 2018: Good News!

I didn’t go flying today, but my co-workers at MAG Aerospace did. They had a long day, arriving home just in time to catch some pictures in the evening light.

First home were John Sweeney and Andy Zabloski. Andy flew, John took pictures.

Blindfold Lake shines in the foreground of this picture looking west at Bigstone Bay with Hay Island in the distance. To the left, Andrew Bay looks open, but south of the Barrier Islands looks like there’s a huge area of ice remaining. Click on these pictures to see the high resolution version that you can zoom in on.

In this second shot, the plane has moved closer to Route Bay. Bigstone Bay is almost entirely open. The most ice is between Hay Island’s Needle Point and the mainland’s Heenan Point, and it’s just soft pan ice.

Hay Island, Moore Bay, Bigstone Bay. More water than ice now.

Scotty Island is just above the aircraft’s nose, and beyond that is the Manitou. Whiskey Island is still ice-locked, but all the ice looks soft and ready to disintegrate. Ptarmigan Bay and Clearwater look open, and I had a comment from scowtan2015 this morning to say that Clearwater’s ice blew out last night.

Town Island in front of the King Air’s nose this time, and everything is open around Treaty Island, Rogers Island and Galt Island now.

The next batch of pictures came from airline pilot Matthew Render, a regular guest contributor. He supplies me with pictures of Shoal Lake.

Matthew took these at six o’clock this evening; the pictures look north. The first one shows the west shore of Shoal Lake: everything is clear north of Twin Points including Rice Bay, Snowshoe Bay and Indian Bay. I’m not so sure about the north shore: cloud cover makes it hard to see if there’s ice or not.

Matthew’s second photo has Dominique Island in the foreground, and there’s still plenty of ice in view, but Matthew says it retreated a lot in the twelve hours between his morning flight and his evening flight today.

Caroline talked to a guy from the Sioux Narrows area this morning, and he said Long Bay cleared out last night.

Summary: vast areas of Lake of the Woods are open now, and the remaining ice is weak and floating loose, but cloud cover blocked the satellite cameras today, so we can’t get an overview of the whole lake.

More pictures are coming from my co-workers. Two other MAG Aero crews landed after Andy and John did. They’ll send me pictures this evening, and if their photographs cover different areas I’ll get them up late tonight or early tomorrow morning.

Thanks to everyone who pitched in to help with Ice Patrol today!

May 6, 2018: Satellite Update

I’m back in Kenora, and the lake didn’t melt while I was gone. Not all of it, anyway.

Here are today’s satellite images, starting with the true colour picture from Terra satellite. There must have been big changes near downtown Kenora, but there’s just enough cloud in the top right corner of these to obscure that part of the lake.

The false colour version makes it clear that the lake is still more than 3/4 covered in ice, but it’s all weak and breaking up. It will be gone soon.

To see a reference picture, with some landmarks labelled, visit the FAQ page.

I’m not scheduled to fly tomorrow, but if I can talk a friend into to taking a couple of pictures, I will.

IN THE MEANTIME, CHECK THE COMMENTS: PEOPLE ARE POSTING FIRST-HAND REPORTS.

 

May 4, 2018: Updated Graph

I’m out of town for the weekend, so no new pictures, but I did get an updated graph from Sean.

May4

The actual daily mean recorded by Environment Canada is  is shown as the string of blue dots. Notice how close it is to the yellow line, which is Sean’s prediction based on the weather forecast. Nailed it!

That means we’re staying on track for a fast thaw, and if we keep it up for another week, we’ll be ice free!

A note on how this prediction works: Sean starts his graph on the day when the average temperature (daily mean) goes above freezing for the season. False starts in March don’t count, so that happened on April 17 this year.  Then he looks back at how cold the winter was to get an idea how thick the ice is, and he uses data from years with similar winters to estimate how many warm days we’ll need to melt it.

This year, he estimated we’d need a “thaw index” of 200. Last Sunday, when we hit 25 degrees, we had a mean temperature of 16, so he adds 16 points towards our target. On Tuesday, we had a cold day, and only managed to add two and a half points.

The initial guess, based on an old mid-April forecast that turned out to be pessimistic, (dashed yellow line) was that we’d rack up the desired index of 200 by May 18. That’s reasonable: one month to go from above freezing to fully thawed is realistic for a late spring.

The fastest spring thaw in recent years was 2007, and is represented by the red line on the graph. It took just three weeks. The weather forecast we had in April didn’t look that promising.

But now we are getting close to having a thaw that fast! Sean’s revised estimate, worked out when the May forecast called for warmer temperatures, is that we might be ice free by May 11. That would be 24 days, compared to 20 in 2007. That’s still a forecast, not a guarantee, but we’re staying on track so far.

The Victoria Day weekend is no longer in jeopardy, and we have a good chance of the lake being entirely open for next weekend.

Boat access to islands close to Kenora, such as Town Island and Scotty Island, should now be just days away.

May 3, 2018: Winnipeg River

My flight today didn’t take me over the lake or close to Minaki, but we did briefly fly north of Kenora, so I did manage a couple of shots of the Winnipeg River from the south end.

The first picture looks north west from over the north end of Dufresne Island. The white stuff near the nose of the airplane is just a wispy little cloud. Locke Bay and Muriel Lake are in the middle distance. Still some ice there.

For this second shot, we’ve turned more north, so you can see Big Sand and Gun Lake near the horizon. Both are frozen. Closer to the foreground are the mouth of Locke Bay and Laurenson’s Island. The streaky bits at the bottom are the same cloud as in the previous picture.

That’s as close to Minaki as we went before we needed to turn towards the airport.

This is Lower Black Sturgeon, seen from the west. The ice there is melting along the shore and looks like it could go completely in the next few days if we stay warm and sunny. Silver Lake, visible in the distance, is a deep lake and will take much longer.

Kenora has three suburban lakes: Rabbit Lake, Round Lake and Laurenson’s Lake. I photographed Laurenson’s the other day, and it was starting to go. Today Round Lake, the smallest of the three,  went completely in a matter of hours. In the morning it was icy. By lunchtime it was opening up, after lunch there was only a small patch of candled ice at the downwind end.

I will be out of town for the weekend starting tomorrow, so there will be no fresh pictures for a few days. I won’t have access to my desktop computer, only my tablet,  so I will be limited  guest photos, if there are any, and updating the satellite links.

I expect the thaw will carry on without me.

May 1, 2018: Good News!

It seems as if our recent warm weather should be moving us towards an earlier thaw. But by how much? My gut feeling was that three very warm days should advance the ice-out date by about three days, but I’ve been holding to my estimate of May 15-18 until I could get better analysis. That arrived today, from Sean C.

His newest graph shows what rapid progress we’ve made, and that the latest weather forecast suggests a faster melt will continue. If your browser has shrunk the graph to fit your screen, you can click on the graph to see it at full size.

Here’s a summary for anyone who doesn’t remember, or didn’t see the old graph: the steep red line represents a really fast thaw (2007), while the green line shows a sluggish spring (2004).

The general idea is we need enough warm weather to melt the winter’s ice. For a cold winter like we just had, we need a thawing index of about 200, marked by the horizontal dotted red line.

The blue dots represent our actual progress towards that target, based on our recorded daily mean temperatures. You can see that we’ve been piling on the warm days, almost matching the red line.

The dotted yellow line is Sean’s old forecast from the previous version of this graph. It’s based on the long-term weather forecast we had in mid-April. He used the forecast high and low to estimate the daily mean temperature as halfway in between, and plotted a prediction based on that.

The solid yellow line is Sean’s new prediction for daily mean temperatures based on the latest forecast. You can even see how today’s cool, cloudy weather set us back a little: look how the yellow line drifts away from the red after the last blue dot.

Sean looked back at the actual highs and lows recorded each day and compared them to the mean temperatures calculated by Environment Canada after the fact, and he’s learned the mean is likely to be a degree or two warmer than the midpoint. He’s revised his new yellow line accordingly.

As we get into May, we’re not using such long-term forecasts as we were two weeks ago; Sean can now work mostly from the fourteen-day outlook. The newest forecasts are milder, so overall, the outlook is quite a bit better.

Sean’s new track shows us thawing by May 11. That sounds about right to me.* Remember, we’re talking about 100% ice-free on Lake of the Woods. Your favourite island may be reachable before that date.

*Sean’s graph is temperature oriented, but we could still have variations in humidity, wind and sunshine that could speed things up or slow them down. I like to give a range, so I’m hedging my bets and saying May 10-15.