There is no reason for a cyclist to ever suffer from cold hands during winter rides—there are so many options available I am sure you can find something to keep your hands toasty warm even in the worst of conditions. If you love long rides in harsh winter conditions you should consider getting a pair of Bike Poagies (aka, pogies).
Bike Poagies are manufactured and sold by Dogwood Designs, a small business located in Fairbanks, Alaska (and those folks know what cold weather is really like). Bike Poagies fit over standard straight bicycle handlebars and allow you to slip your gloved hands in and ride in warmth and comfort. They are extremely lightweight, but offer an enormous amount of insulation around your hands.
Bike Poagies have a durable nylon shell on the outside, polyester insulation in the middle, and a nylon taffeta lining. There is also a lightweight internal skeleton to make sure the Poagies hold their shape. To attach Poagies to your bike you just slide them over your handlebar and then cinch them down around the bar with the attached elastic strap. There is also a gusset where you put your hands into the Poagies that you can close to keep the cold air out. However, I leave mine open most of the time because my hands get too warm when the Poagies are sealed up too tightly. If your bike has bar ends (like the Ergon GC3 Handlebar Grips) these Poagies will fit over them perfectly and allow you to still use several different hand positions. Bike Poagies are roomy enough that you can store a couple of energy bars or gels in them to keep them warm (or a chemical hand warmer if needed).
Standard Bike Poagies are good down to around -15 Fahrenheit. Dogwood Designs also offers Poagies Plus which are supposed to be good down to around -40 (I’ve never had a chance to try these out for myself). Both versions of Poagies are available with an optional reflective trim if you have to share your route with either cars or snowmobiles.
Bike Poagies sell for $95, and the Poagies Plus sell for $148. The optional reflective trim is an additional $12. Both versions of Poagies are available in an unbelievable seventeen different colors: Red, Royal Blue, Yellow, Neon Green, Hot Pink, Safety Orange, Electric Watermelon, Purple, Gold, Forest Green, Charcoal, Light Gray, Navy, Kelly Green, Chocolate Brown, Olive Green, and All Black.
The folks at Dogwood Designs do not have a Website. However, you can email them at firstname.lastname@example.org for a current brochure (they will send it to you as a PDF file).