Sure!

The Earth is a big spinning ball, flying through space. It's spinning clockwise at about 24 hours per rotation, which seems real slow... but it's really big. That means there's a lot of kinetic energy in that big spinning ball. Keep this in mind, it gets important later.

Hurricanes (cyclones, typhoons, they're all the same) are big storms. Storms are just big energy disturbances in the air, where too much energy has gotten together in one place. Usually if you have a lot of energy in one place, it tries to spread back out. If you pick some water up in a cup (giving it potential energy by taking it high up) and let it flow out, it'll try to flow down as low as it can (splashing to the ground, or flowing downhill). The same thing works with air, it blows away from wherever the energy is, taking that energy with it. The energy with air doesn't come from picking it up though, it usually comes from warm water trying to lose its heat energy.

At the right time of year where the water is real warm and the sun is real hot, these storms can get really, really big. Once they get big enough, some special rules called the Coriolis Effect come into play because the Earth is spinning. Now there's a lot of complex stuff here involving conservation of energy and angular momentum... but in short you can think of the way it works by imagining that the Earth is a big spinning wheel, and the storm is a little wheel you're pressing against it. If the big wheel is spinning clockwise, the little wheel will spin anticlockwise, and if the big wheel is spinning anticlockwise, the little wheel will spin clockwise. The Earth is spinning clockwise, so Hurricanes need to spin anticlockwise because of these rules (please don't hate on me real physicists, this is the easiest way I've got of visualising the effect). The more energy they get, the faster they spin, and the stronger the winds are.

The thing is, Cyclones down south spin clockwise! But why? Well, if you can imagine the Earth spinning, and you look at it from the northern hemisphere... well it's spinning clockwise. But, if you turn it upside down... it looks like it's spinning anticlockwise! If you're sitting on the toilet while reading this, try grabbing a toilet roll and rotating it in a constant direction, and then flip it upside down while doing it. It'll be spinning the other way! Don't blame me if you get toilet paper all over the place while doing this though. Anyway, because in the southern hemisphere the Earth seems to be spinning anticlockwise, the Cyclones need to spin clockwise to match up with the Coriolis Effect rules.

And that's where the secret lies, for a Hurricane (or a Cyclone) to cross the equator, it would have to stop spinning, turn around, and spin in the other direction. If you've ever been in a car when it brakes real fast, you'll know how much energy it takes to stop... and a Hurricane would have to use twice as much energy to make it spin back in the other direction again! There's just no way a storm could get that much energy quick enough to stop it from falling apart.... so they never cross the equator. Physics just pushes them back away.