The Alaska cruise season is five months long -- from May to September -- but not all Alaska cruises are created equal. From one week to the next, summer in the Last Frontier can see noticeable differences in weather, cruise pricing and what's in season. Whether you're looking to find some savings or spot bears, catch a king salmon or plenty of daylight, you'll have to book accordingly.

To help you set the right expectations for your Alaska adventure and pick the best month to cruise, Cruise Critic breaks the Alaska cruise season down by month and compares nine elements to consider during a cruise there.

A few things to note: Hours of daylight are rounded to the nearest hour and calculated by the average seen in the city of Anchorage; daylight hours in the port city of Seward are always slightly less. Temperatures are measured in degrees Fahrenheit and are based on Southcentral Alaska ports, which include Anchorage, Seward and Whittier; temperatures will vary in other areas of the vast state. Layers is the magic word in Alaska. While we recommend certain things to bring by month, you will want to bring plenty of items that are waterproof, wick moisture and can be layered (yes, this tip applies to socks and underwear as well). Due to the rapidness of weather changes in Alaska, it can be blazingly hot, damp and cold or severely windy -- all in a one-week cruise.

One final note. The truth is any month is a good month to visit Alaska, but locals tell us the very end of May and beginning of June offers some of the most beautiful weather. (Plus it's not at the height of crowding because most children are still in school).

May

Pricing: The Alaska cruise season begins mid-May, when temperatures start to warm. These first sailings are considered "offseason" and prices tend to be lower, particularly the first week of the season. Some sailings can be found for prices from £100 per day, but with the competitive nature of Alaska bookings, even May cruises aren't always a safe bet for having available space if you don't book in advance.

Weather: May is the driest month of Alaska's cruise season with just a 25 percent chance of rain. The average high is 54 degrees and the average low is 39 degrees.

What to Pack: You'll likely need a warm winter jacket to brave the Alaskan evenings in May. Unless you're bringing them to put under one or two other layers, T-shirts with short sleeves can be left at home -- you won't want bare arms this time of year.

Hours of Daylight: 17 hours

What to Watch for: If you're looking to hike the tundra -- treeless mountain tracts -- the snow doesn't really begin to melt until late June, which could prove tricky for maneuvering.

What's in Season?

Harvest: Asparagus begins to show up on farm-to-table menus, but for the most part, the Alaska growing season begins in June and July.

Wildlife: Spring (the earlier the better) is a great time to view wildlife because the trees aren't fully in bloom, meaning you can sneak a peek at critters between the branches. Once the green vegetation takes hold, Dall sheep, mountain goats and black bears are lured into areas where they are easily observed, according to the Alaska Department of Fish and Game. Migratory songbirds and seabirds also start to gather at southcentral nesting colonies.

Fishing: King salmon runs start in late May. Also beginning in late May through early July, the fishing is good for Arctic char (not to be confused with the near-identical Dolly Varden trout). Even if you're a seasoned fisherman, we recommend using a local guide to help find you the best fishing spot.

June

Pricing: June is a sweet spot before the influx of families and crowds (especially earlier in the month) and yet is still considered peak season so you'll see that reflected in the price of your cruise. Average starting prices for a weeklong sailing are in the range of £800 to £900 per person.

Weather: With a high of 62 degrees, a low of 47 degrees and relatively little rainfall as compared with the rest of the summer months, the weather in June is optimal. Long daylight hours add to the feeling of warmth.

What to Pack: Bring bug spray, long (but light, remember it warms up) shirts and pants, and polarized sunglasses for the many hours of sun reflecting off glaciers. (These are good to bring anytime.)

Hours of Daylight: 19 hours

What to Watch for: Mosquitoes. While everything is in bloom in June and it's picturesque to look at, expect the bugs to be biting. Also, watch for the summer solstice on June 21, which brings nearly 24 hours of sun, depending on how far north you are (Denali is a neat place to be.)

What's in Season?

Harvest: Herbs and greens begin to come into season in June, along with delicious pie fillings like cherries, boysenberries and rhubarb. Look for local specialties in cafes around your port.

Wildlife: Moose give birth around June, so you might be able to glimpse a calf, if you're lucky.

June is the best time to see herds of caribou, but you'll still need to be lucky to spot them. Book a float trip down one of the rivers in the Arctic National Wildlife Refuge in Fairbanks, and the chances of seeing a herd will be pretty good. Bird enthusiast? June is the best month to spot unusual birds such as Asian accidentals in Western Alaska, according to the Alaska Department of Fish and Game.

(Remember, as thrilling as wildlife sightings can be, the best time to see bear cubs or moose calves with their mother is also typically the most dangerous. Always use extreme caution when hiking or doing anything, especially alone, in Alaska. Being prepared for an unexpected bear or moose encounter can be the difference between life and death.)

Fishing: King salmon and sockeye salmon can be found in the waters during June. Rainbow trout begins its run in June and continues through the summer into September (the Copper River is known for them). Northern pike also runs June through September. Halibut fishing ramps up mid-June through August, but is still available for fishing trips in May or September (stick to Seward or Homer for halibut).

July

Pricing: The absolute middle of the Alaska cruise season, July is often the busiest month to travel here, and pricing will be close to full pop. However, you still might be able to book for less than £1,000 per person if you book in advance.

Weather: It's the warmest month in Alaska; expect highs of about 65 degrees with 51-degree lows. Rain begins to blow in with about a dozen inches, on average.

What to Pack: July is tough -- it can be hot or overcast and rainy. Pants that zip into shorts might seem lame but could be handy on all-day excursions. Bring rollable windbreakers or jackets that will fit into a day bag if you start breaking a sweat.

Hours of Daylight: 19 hours

What to Watch for: Many events around the state mark the Fourth of July. Two of our favourites are the Girdwood Forest Fair, with music, crafts and cultural events, which takes place annually in this small resort town outside of Anchorage and the Mount Marathon race in Seward.

What's in Season?

Harvest: July is when the growing season really gets in gear -- strawberries, tomatoes, cabbage, gooseberries and tons more will begin to find their ways into recipes and onto your plate if you eat in town.

Wildlife: Bear viewing coincides with the salmon runs, so it makes sense that with so many salmon in Alaskan waters, chances of seeing bear could increase in July. It's also the best month to visit seabird colonies from Southeast to Northwest Alaska, according to the Alaska Department of Fish and Game. Fur seal pups are born and Steller sea lions give birth beginning in July. If you're adventuring north near Nome, walruses "haul out" on Round, Little Diomede and King islands.

Fishing: King salmon can still be caught in early July; sockeye run through the month. Pink salmon can be found beginning in the middle of the month. Silver or coho salmon also begin their run in July.

August

Pricing: August is the end of the peak Alaska cruise season, so you might start to see some deals edge in late in the month, but expect full fares, for the most part.

Weather: In August, the chance of rain is more than 50 percent, so expect a few parades to get rained on. The high is 63 degrees and the low is about 48.

What to Pack: Plenty of rain gear including waterproof shoes and wool socks (wool dries much better than cotton).

Hours of Daylight: 17 hours

What to Watch for: The Alaska State Fair, which takes place in the Mat-Su Valley, is late in the month and typically runs into the first few days of September. The Talkeetna Bluegrass Festival combines camping, handicrafts and of course, bluegrass -- the music has been known to play up to 20 hours per day.

What's in Season?

Harvest: Blueberries! The Alyeska Resort hosts its annual blueberry festival in late August with everything blueberry you can imagine; about a week or so after, the nearby Girdwood Fungus Fair celebrates all things mushroom.

Wildlife: Bears are still in full view with salmon and berries still plentiful. Bald eagles can also be seen congregating near salmon-spawning streams.

Fishing: Pink salmon runs until mid-August and silver runs through the month. Seward's Silver Salmon Derby is always the second week of the month, one of the oldest and largest fishing derbies in the state. The Dolly Varden trout in late August were practically jumping into our boat on the Upper Kenai.

September

Pricing: The end of the cruise season and the beginning of school mark September as a quiet and lower cost time to head to Alaska. If you're lucky you might find a last-minute deal, but more and more cruisers are looking to book a holiday in the region regardless of timing, leading to early sellouts even for September sailings.

Weather: September can begin to get cool, and on top of that it's as rainy as August with up to 14 days of rain, meaning there's a good chance one of your excursions could get rained out. Temperatures drop to a high of 55 and a low of 41 degrees.

What to Pack: Bring heavy layers that will keep you warm but also stay dry.

Hours of Daylight: 14 hours

What to Watch for: If you're travelling in early September and can make it up to Fairbanks, there's a chance you might be able to catch a glimpse of the northern lights. Time and weather conditions play a major role, but it's one of the few perks to cruising toward the end of the summer.

What's in Season?

Harvest: Most crops remain in season through September.

Wildlife: According to the Alaska Department of Fish and Game, moose, goats, caribou and muskoxen mate in early autumn, often in open areas, and antlered male moose and caribou might be seen sparring. Despite the weather, this is still a good time to catch moose and other animals at Denali National Park, and bears can still be seen near berry patches and streams with salmon. Gray, bowhead and beluga whales migrate along the west coast.

Fishing: Silver salmon