The crouching you mentioned is for the lightning crouch position... crouched down on your toes with your heels touching, covering your ears. Google “lightning crouch position” for an example.

Not sure why you would leave the tent though? I get that there’s aluminum, but if your tent is surrounded by tall trees, and if lightning did happen to strike in your immediate vicinity, wouldn’t it strike the tall trees rather than your very low (aluminum) tent?

For me, if I’m mid travel and I see lightning, I get to shore ASAP and try to find decent cover. I feel safe getting back on the water 10-20min after lightning, if the skies look good. If skies still look bad, I’ll stay longer. If I’m already on campsite, I usually stay in the tent or under a tarp and wait it out.

Thanks for the replies - the worst of any of the thunderstorm stuff will probably be my son.  We got caught in the canoe in a bad one, just barely got out of the water and back to a tent in a state park when he was little, and it was banging like crazy with a very foreboding sky for several hours.  He's been apprehensive of thunder/lightning ever since, can't say I blame him.  He'll be sleeping in a hammock....probably safer than any of us relative to lightning, but I'm sure feeling more exposed since he won't have a cuddle buddy.  If we get a big banger overnight my wife and I will probably get a visitor, and that's fine.  He's a good kid, I don't mind sharing space with him!

This trip is a little different in that my entire family is going - for the first time all of us, and my daughter's bestie is going as well, so I have charge of somebody else's daughter, which makes me nervous.  She'll be fine, but I need to make sure I take her back home in one piece!  Also interesting because this trip is kind of a milestone for my wife.  Some medical issues last year at this time resulted in terrible walking/balance issues, and she's worked so hard on physical therapy - she's ready to go.  Six months ago she needed a cane, today you'd never know.  I'm saving some of this for a trip report that I hope will share her great success, but it should be something else.  We are going Magnetawan, to Casey on Day 1, then through Rain to Jubilee on Day 2, then day 3 looping up through the Petawawa (upstream) to Daisy....then out on Day 4.  Nothing super-exotic, though Day 3 will be six carries and our longest day for sure.  I've been to all of these places before, but some of those places it has been 25 or 30 years, and there are a few special places along the way - the first place I ever saw the park, the place where I camped one time with my dad, etc.  I'm almost looking forward to the trip report more than the trip!

This sounds like a wonderful trip with the family!

Weirdly enough, I get less scared of thunderstorms when I'm in the backcountry than when I'm home inside my house (I realize this is NOT rational).

We always make sure to get off the water at the first sound of thunder. If it's threatening to storm but hasn't hit yet, we'll continue paddling but be constantly eyeing the best place to take out. We'll ping pong from good take out spot to good take out spot so we're never far from shore if it does hit. If we were on a river with high cliffs, I'd probably play it safe and not paddle that section until the storm passes. 

Like Uppa, we hang out under the tarp and enjoy the show. If we're stopped just on shore and not at camp, I put my pack under my canoe to keep it dry and take cover from the rain in the trees staying away from widow makers or super tall trees. The actual storm part never lasts that long. The rain may continue but the storm passes fairly quickly. 

I've also stopped before at other people's campsites and taken shelter with them under their tarp. Anytime I've done this, people are so friendly. One family made me a hot chocolate and another group shared a beer with me! 

I know you're supposed to get out of the tent (so you can see if a tree is about to fall on you) but if it storms at night, I just snooze through it as best I can. I do always make sure to double check that the tent is set up in a storm safe spot (no dead limbs above, not in a hollow that might fill with water and not at the top of a hill). 

Just set up a couple tarps over common areas and you can still be outside enjoying the storm from a dry position.  I've been in a few storms in the park and my best advice is to have a tent you dont have to worry about leaks or set a tarp over the tent as extra protection, and set up at least 1 big tarp tied to trees over an area you can all sit or stand under.  It's nice to have an area outside to make some food, coffee, hot chocolate, etc while watching the storm show.

Should this be in the winter camping area?

Uppa beat me to it ... I just stay in the tent ... honestly I usually fall back to sleep and my kids are pretty much used to it too. 

However if thundershowers are forecasted and given the choice I do choose a campsite that is not below the tallest tree in the area ... unless its a shang gra-la site then its worth the gamble.

We were camping on Big Crow one time at the ranger cabin (wind bound) and that night lightning blew the top off the fire tower on the hill just behind us.  We heard the lightning and knew it sounded a bit different when it hit ... but didn't realize what had happened until we paddled out and looked back at the mountain the next day.  So never camp right below a fire tower either .. ! 
 

I have watched it,  i was on south eastern side of macintosh lake on that Friday, 2 tree came down on our site. Met a guy on the 935 port out of misty (while we were navigating a blow down from the Friday storm) who told me he had a tree come down on his site on daisy during the wind.      What a crazy day that Friday was.  Macintosh looked like superior in the late afternoon.

I didn't get into the park until Monday the 24th, after the storms.  However, I can only think that what I saw on Cork was due to the storms.  Here is a pic of the path to the thunderbox on the southern most site.  Both sites had multiple blow downs.  I would not have wanted to be there when they all went down.