We had 5F on Christmas eve, here north of Seoul, and I was out there growing eyelash icicles for my early Festive 500 kms. I have a cheap pair of gloves from the LBS that I was wearing, and for the first time ever, my hands stayed dry in them. Normally they turn into micro saunas and your hands are swimming, but warm, at 20-30F. I often use softshell fleece gloves from Decathlon, like this morning on my Festive 500 commute, that are cooler, but dry inside at 20-30F. I have Northwave winter boots (MTB SPD clipless) that are sort of okay; it's my one weak spot in my winter gear. I wear double socks and things are okay at 20-30F, but that 5F morning was brutal.
We had a heavy band of snow roll through and the high pressure system that was pushing it along hung around after it, dropping temperatures through the floor and freezing the bloody snow in place. Down in Seoul the local city wards have mainly done a good job of clearing, but some *cough* Dobong Gu *cough* have large sections of bike path that are unrideable. I guess their snow removal budget was picked over earlier in the year for flood clean up, the cash ran out and now we have half a foot of churned up dry snow lying around up there on the main north-south bike path in Seoul. Get past there, though, and Dongdaemun Gu's path is like normal. Really frustrating TBH. Uijeongbu paths have thin openings separated by snow ridges, thawed and frozen into ruts. You need goggles if you have that sort of thing near you, because if you're wearing a lycra face mask below your fleece balaclava/tube scarves, the condensation from your breath will hit the glasses and freeze in place. Closed goggles are okay/a bit better. To avoid the worst of the ice/slick packed snow, you need to see where you're going.