Heavy rain to come across central and western Scotland through Saturday and Sunday.
Latest forecast totals look like this to midday Saturday....that's 40 to 80mm across a large swathe of central and western Scotland ...

The midday to 1am Sunday period shows further rain totals of 20mm+, although this is eased c compared to the morning ...

Sunday morning, 1am to 1pm shows the rain focussed a little further north with a further 20mm over the Highlands, but easing further south.

All in all a weekend to be prepared for some localised flooding and, combined with the chill, one to be very wary off it walking.
More on mountain weather conditions this weekend at our sister weather forecasters www.MWIS.org