having dived commercially for years cold hands part of the norm look at the northern diver web site for titanium lined neoprene gloves they reflect the heat back if you put a pair of surgical gloves on too much warmer. i also use fur lined rubber gloves for the boat you can buy them with latex seals to keep water tight, the secret is layers to trap air so the sking stuff very good with the down type material too.
once the hands are cold tough you need to warm up chemical hand warmers are good especially the reusable ones where you boil them up to reactivate plus charcoal hand warmer they last a long time.if using neaprene take a flask of hot water rinse them and put straight on the layer of water stays warm. lastly the tail tale off the engine at tick over can be a lot warmer than ambiant tempratures just to get the circulation going again in the extrematies.
Try Endura Strike waterproof mountain bike gloves. I wear them all winter on wet windy cold rides both commuting and off-road. I'm usually 60mins each way on a commute and longer off-road on days when it's too bad to take the rib out.
I've tried neoprene gloves and ski gloves and these win (ahem) hands down
Ski or motorcycle gloves tend to be the gauntlet type which will funnel rain off your sleeves into the gloves so not much use. Neoprene gloves are great most of the time but if you're out for hours in continuos cold rain eg SAR work your hands will suffer. Showers are ok but continuos rain just takes the heat out of the gloves and your hands . Maybe a pair of rubber gloves over the neoprene might do the trick but haven't tried it yet. As someone else said if your hands are cold before putting them on your hands will never warm up in neoprene gloves.