You should try with a powered hub, a pi really needs one for a device which consumes significant power, like a weather station. That said, I'm not sure how much power a Davis stations needs to draw from the USB port, given that it has its own power supply.
At the moment, we are at a caravan park close to
Inverewe Gardens in the North-West of Scotland. We're spending Easter here before moving off North again, probably arriving back home in Sanday a week on Monday, after seven months away.
This the view from our van today:
inverewe.jpg
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