The Channel Islands are five outstanding islands. Great kayaking and snorkeling are to be had here. I've gone twice, both times in Summer, so that's all I can speak to.
The five islands are accessible by plane year-round though by boat only Anacapa Island and Santa Cruz Island. However, accessibility is always weather depending. The other three islands San Miguel, Santa Barbara, and Santa Rosa are accessible by boat from April to October/November. Boat trips are not offered daily. Booking in advance is essential. Check the conditions and closures of the islands first. Channel Islands Conditions
Most visitors come during the summer from June to August. Due to the limited transportation opportunities, it doesn’t get too crowded.
The islands have a cool Mediterranean climate, but weather varies considerably from island to island. The winter is cool and wet - summer is warm and often dry. Most precipitation from November to April with its peak in January and February and drier from May to October. Summer is the driest period. The climate is influenced a lot by the sea. Fog may appear, especially on the outer islands during the night but can occur at any time. The islands are often windy, and strong winds occur on the outer islands. Strong eastern winds from October to January. Sea temperature is around 50°F (10°C) in winter and around 65°F (18°C) at the end of summer.
Each season has its own character, different weather, and outdoor activities. The best time to visit one of the islands depends on what you are looking for as well as the activities you’re planning:
Snorkeling: It's snorkelers paradise and best at the end of summer until fall with a sea temperature of about 65°F (18°C). A wetsuit is recommend to stay longer in the water.
Watersports: Besides snorkeling, summer until fall is also the best time for sailing diving, kayaking, and swimming. Many consider early fall as the best time of year for diving or snorkeling as ocean temperatures go up to 70° (F) and visibility may reach 100 feet.
Whale Watching: January until March has the highest chance for gray whale sightings.
April to September is the season for blue and humpback whales due to the high plankton concentration. Year-round spottings: orcas, minke whales and different species of dolphins. Besides, it is common to spot seals, sea lions and water birds.
Birding: Birding is outstanding in the Channel Islands. Some endemic birds occur here like the Island Scrub Jay on Santa Cruz Island. Best time is the nesting season in spring. Shorebirds are best seen on Santa Cruz, Santa Rosa, and San Miguel.
Surfing: In the winter and spring the north shore is best, and in the summer and fall it’s the south shore. Best access to all surf spots by private boat due to the remote locations. Besides being one of the best times for surfing, in the winter also some of the best sunsets occur.
Wildflowers: Depending on the amount of rain from the end of winter until spring some continue to bloom during summer. Gumplant, buckwheat, poppies, and verbena can still be viewed in the summer.
Yellowstone's abundant and diverse wildlife are as famous as its geysers.
Where animal sightings happen, depends on habitat preferences, weather and seasonal cycles of movement. Still, it's often a matter of luck but you can increase your chances by following our monthly guide. Read our full guide below and find out which animal can be seen in which months and season (spring - summer - autumn - winter). And if you want to make the most out of your wildlife visit, consider this incredible private tour: Private Yellowstone Wildlife Tour (with extremely knowledgeable, friendly, and professional tour guides. You'll remember this special tour forever!)
April - Early June (Spring)
Most animals can be spotted in or near the valleys. It's the time for baby bison, baby moose, baby bear, baby elk and many more. Also a good time to spot wolves and grizzly bears. Grizzly sightings occur mostly at night, dawn and dusk. A great grizzly bear spot in spring is the shores of Yellowstone Lake. Gray wolves are often seen in Lamar Valley and Hayden Valley.
Mid-June - July - August (Summer)
Bears and other animals leave the valleys and head for higher areas in June/July. But still, visitors often report bear sightings throughout June. Later in July and August the chances to spot grizzlies or black bears in the valleys are very low. However, bison are still there, starting to rut in early August. Warm, great weather but also peak tourist months.
September - October (Autumn)
Animals return to the valleys. Elk rut throughout September. The fascinating rut can be witnessed up-close in Mammoth Hot Springs, near the northern entrance. Together with amazing fall colors it’s one of the best time to view or photograph almost every animal including elk, moose, bighorn as well as wolves and grizzly. Visitor wise it gets slightly less busy in September after Labor Day weekend. However especially weekends are still busy. In late September/early October the crowds start to dissipate.
November December- January - February - March (Winter)
Winter in Yellowstone! A magical time and least crowded. Most animals are in or near the valleys. Some can be spotted near the steaming geyser basins. Winter is the best time to view wolves. You can also observe bison, elk, bighorn and others. Also, a really great time for photographers, since animals are easier to spot against the snow. Grizzly bears can't be spotted, since they hibernate in winter until mid-March. Finde more tips for a winter visit on the official NPS website: Visiting Yellowstone in Winter. Especially useful are the lists with open facilities in the winter and the warming huts. One thing we'd always do again in winter, is a snowmbile tour. That's an amazing experience. We can recommend these guys (they are excellent!): Full Day Snowmobile Tour from Jackson Hole (Tip: bookmark the link). The best lodging in Jackson: Inn on The Creek (via booking.com with price guarantee)
Time of Day
The best time of day for wildlife viewing is either dawn or dusk: Animals usually feed during the early morning and in the evening. That's why they're often more visible at these times as they're up and moving around. In general dawn is even superior: Be at the valleys just before at sunrise and stay until 9 AM. It's also less crowded. However, dusk is also great, particularly for elk viewing in Sept. Sunrise - Sunset Yellowstone
Avoiding Tourist Crowds
Yellowstone National Parks gets heavily crowded in the peak summer months. If you plan a summer visit, book your hotel well in advance.
The most crowded months are June, July and August: Congested roads, overflown parking lots and the popular places are packed: Old Faithful, Grand Prismatic Spring, the Grand Canyon of the Yellowstone, Mammoth Hot Springs. The month of May is still moderate visitor wise. However, it gets very busy on Memorial Day. Later in September visitation starts to drop off after Labor Day weekend. However, it's still busy, even more so on weekends. In late September the crowds start to thin out. In October it's getting a lot quieter again.
How to avoid the crowds during peak months? Arrive early! The rush hour in YNP starts between 9 and 10 AM. Get up as early as possible! Another way is to dodge the crowds is by staying late: The main attractions are packed between 10 AM and 4 PM. Get there later, as it doesn't get dark before 9 PM anyway. Another big advantage when arriving early or staying late: You'll get to see more wildlife at dawn or dusk (see above). Extra tip: Check the official NPS Webcams a few days before you arrive during certain daytimes.
There is one word which is true for Yellowstone's weather: Unpredictable! Temperature drops and rain can happen almost any time in spring, summer and fall. Thunderstorms in summer are common in the afternoons. Bring layer of clothes and always rain gear.
If you'd like to avoid snow completely, then don't visit before May/June. It still can snow in June at some places but it will melt very quickly. By late May the valley floor is usually snow free. In higher elevations you may still see some snow in late May and June. That's important to know if you go hiking. After the summer you can expect the first real snow in October. As a local expert says: 'You can count on snow on the ground in Yellowstone by Halloween!'. However, never let the snow stop you from coming. October is an excellent month: Quiet and still so much wildlife to spot! In spring late April and May are our preferred months, regardless of the snow. Just keep in mind that until late April it still can feel like winter!