October in Yellowstone

Seasonal Phenology Notes from the Greater Yellowstone Area

On this page you’ll find October phenology notes for Yellowstone and surrounding areas (mainly Cody, WY). If you’re wondering what it’s like in Yellowstone in October – browse through to get an idea.


October 1

  • 2014: YNP | Upper Geyser Basin – First snowfall showing on the webcam this morning.

October 3

  • 2016: Had a soaker of a rain that left Cody 1.5″ of rain. I’m sure it’s snow higher up.

October 4

  • 2016: Snow was on all the high mountain peaks this morning and Sylvan Pass was closed since late yesterday due to snow.

October 5

  • 2016: Cody WY – While at Cody Coffee in the old airport, I saw a pair of Trumpeter Swans fly over and land somewhere beyond Alkali Lake.

October 7

  • 2014: Cody | Buffalo Bill Reservoir – Still seeing American Pelicans today. A few Bluebirds are still around, though.

October 8

  • 2016: Sylvan Pass & East Gate area – One Bison seen at Mummy Cave area. Another bison was above Sylvan Lake and heading east with a bad limp. He was gruffing and had his tail raised with cars that slowed for photos, so I’m guessing he might have been tapped by a car. On my drive out of the park, I saw him again and he had almost reached the east gate and wasn’t limping quite so badly.

October 10

  • 2016: Wapiti WY – Mule deer started to return to their winter grounds in Wapiti.

October 11

  • 2016: Cody WY – First measurable snow this morning of 1/4″ that melted off. Snow showers through the day that set in for good in the evening.

October 13

  • 2014: Cody | Wapiti – Saw 3 Mountain Bluebirds today at our house – possibly the last day. (JW)
  • 2014: Cody | Buffalo Bill Reservoir – Two American Pelicans still hanging out. The dust abatement dike from the Northfork is just above or slightly below the water level. (JW)
  • 2015: Cody | Wapiti – Report came in that the Mule Deer are returning to their wintering grounds.
  • 2016: Cody WY – Woke to 4″ of snow this morning on the grass and deck – heard they got more out east of town.
  • 2016: Yellowstone | Sylvan Pass – Another bison was making his way over the pass to spend the winter along the North Fork.
  • 2016: Yellowstone | West Thumb G.B. – Needle ice had formed overnight.

October 14

  • 2016: Wapiti WY – a report came in of winds on some high ridges above Wapiti that reached 82 mph and 100 mph (gusts).

October 17

  • 2014: Cody | Wapiti – A large grizzly bear was encountered in the Wapiti area (JW – report from neighbor PF)

October 21

  • 2015: YNP | Mary Bay – Trumpeter Swans returning for the winter. One group had two adults and 5 cygnets.

October 23

  • 2016: Sylvan Pass & East Gate area – On my way driving into the park, saw one Bison seen at Newton Springs. One Bison on the road coming down off the pass heading east. One Bison on the road heading east at Lake Butte Overlook. One Bison at Sedge Bay Dome (but the herd was just over the hill at Mary Bay, so not sure if he was migrating to the North Fork for the winter). On the way out, there was one at Steamboat Point (mayee the one that was at Sedge Bay?) and one at Cub Creek (maybe the one that was at Lake Butte Overlook earlier?).