With the weather starting to shift and overnight lows dipping into the 20's, and even teens to zero in some sections of the canyon, Boulder Creek is in a winter slumber right now. The lower reaches closer to town will be the most consistent due to warmer temperatures, while above the tunnel is iced over. The ice is starting to get thick from the Boulder Flycaster's hole all the way up to Castle Rock. Above Castle Rock the creek has a bit of open water, but the flows are extremely low, clear, and cold. Your efforts will do best if focused around Four Mile Canyon and closer to town during winter. During warming trends venturing farther up the canyon can be more productive, but only if overnight lows are staying close to freezing. Small bugs have been working better recently with the colder temperatures, but terrestrials will still dray strikes from sluggishly cold trout. Warm days will be best for the top water bite, but dry dropper, and double dropper in deeper plunge pools will still be the way to beat them up. Look for the best fishing to be during warming trends when daytime highs are in the 50's, and before storms roll in. The partly cloudy days before a storm can have you fishing dries all day long. Through town the fishing has been best in the deeper holes and pools. Fish stack up in these areas for winter and you can pull numerous fish from one pool by resting it for a few minutes between fish. Try san juans and leeches along with small buggers and crawfish patterns along the bottom. Dry fly fishing will be best with small mayflies and midges, and beetles and ants do surprisingly well deep into the winter, especially on the warmest days. You can catch fish in Boulder Creek every month of the year! You may be limited to town on the coldest days, but the fish are always looking for a small san juan in the winter. Small zebra midges do well all winter as well. Close to the shop this is our home water that we have people on almost every day.