Putting ITUProp to the test

There aren't too many WSPR stations emitting from the far northern regions of the world.

Over the past few weeks, a Canadian ship has been making its way along the North West Passage, running a 200mW WSPR beacon as it goes.

It's become clear that CG3EXP, the beacon on the ship, is heard quite consistently around 16:00UT daily, here in Wales.  The tiny signal generates a receive report here of around -20dB SNR.

How does the ITU propagation webware fare against this reality-check?

Here's the point-to-point prediction, based on the last known position of the ship and my receiving position.

Clearly, the prediction is pretty accurate!