In mulling over a 2012 Denali climb, I note that RMI does trips from mid-May to mid-June. What are the pros and cons of early versus late? Given how cold it gets, why wouldn't you always want to do it in June? Thanks!

Earlier:
Colder
Some say more stable weather
Less crowded
More work establishing camps

Later:
Warmer
More crowded
Camps often already established
More cracks open up

May climbs are cold and a lot of work. Your chances of summiting are pretty low and your chances of frost-nip (or worse - frostbite) are pretty high. Personally I prefer June... it's crowded but the temps are much nicer.

Don't go there guided (my group went unguided and I think it helped a lot. We spent less time lower down and more time at 14-17K acclimating for summit push) and if possible do not use west buttress. It is wayyyy too crowded. It is basically a marked trail all the way up. Every exposed section has fixed lines or tons of fixed pickets. If you do however, I thought going in the late may to shoot for a summit in June worked out perfect for me. We summited on day 11 I think, after waiting out a storm at 17K for 2 days after getting there. If you have decent speed leave for your summit bod before all the guided teams leave 17K camp (before 9am or so) because you will be stuck in a communist bread line for hours! It is very scenic and beautiful but WAYYYY too crowded. The only part I enjoyed is taking butter from the guys who set the new record on Cassin, that was entertaining.
Fact #1 We built only one camp (a half ass job in a storm right after getting to 17K). Next day we moved into a different one with walls.
Fact #2 It is not as cold all the time as people make it seem. When the sun is out and you are at 14K and bellow it is actually pretty warm
Fact # 3 it is a zoo
Fact #4 later in June you will want to travel on the lower glacier at night (snow bridges are stronger)

enjoy

I climbed the West Buttress this season. Our group (guided) flew in on May 9 and based on my experience I think an earlier date in the season is ideal. It is colder, but that can be a positive in that, as others mentioned, you will likely not have to travel at night to avoid weaker snow bridges on the lower glacier. Even for daytime travel you might avoid some unpleasant heat by going earlier in the season; the day our group moved to 14,200 it was surprisingly hot, so I have to imagine it can only get more so later on. Yes, you will likely have to do more work establishing camps. We were able to re-use some snow blocks from an abandoned camp at 14,200, but otherwise built all our own camps. But the major plus, in my mind, is that it is a lot less crowded. On the ascent we did not experience congestion and lines on either the fixed lines or the running pro between high camp and Denali Pass. When we descended from high camp on the 28th, on the other hand, I couldn't believe how many teams were moving up. I wish I had counted, it was crazy! All the camps had to have been twice the size, if not even larger, than when we were on our way up. If I had to do it all over again, I would definitely go for the same dates.

Early is better. May is better than June.

June gets to be too frightening. Too many avalanches, too many crevasses. And it's too damn hot on the glaciers.

I'll never go in June again.

I climbed it in 2009. I agree with the post above- don't go guided. You'll probably end up with extreme knuckleheads in your group. We started climbing May 24 and summitted June 7. The lower glacier was breaking up by the time we descended. I thought late May/early June was perfect, not to mention the eternal daylight. Have fun!

Jthomas,
I recommend going in May for many of the reasons stated above. My group was boots on the ground from May 16-June 2nd (May 30th summit). I found the trip conditions to be much warmer than expected (I realize that is subjective). In hindsight, I probably would have preferred to have started my trip a week ealier. I chose the May timeframe mostly to avoid increasing crevasse danger from warming trends. Even with very high awareness/diligence on the lower Kalhiltna while traveling out, I took funky crevasse fall from which I am still recovering. Ironically, the punch through/fall was due to warming conditions..hah!

Going with a guided group has its benefits and drawbacks. One unique benefit is that you get to meet and climb with some really interesting people from around the country and world. Whether you go guided or with your own group, the most important thing for you to go DO IT!!:) It took me ten years to call my own bluff and get the process going, but I'M SO GLAD I DID IT. It really is an amazing experience. The trip may be expensive and time consuming, but the memories and experience will be priceless. Good luck!

I went in May lasy year and happy I did with the bridges really opening up in June. I am going again in 2012 in May.(13th) Scott

The annual mountaineering reports for Denali include statistics on the busiest summit days. The stats usually reflect the time period for best weather and conditions each year. The busiest summit day varies year to year. It was June 20th in 2010, June 7th in 2009, and May 30th in 2008.

Alpinist wrote:The annual mountaineering reports for Denali include statistics on the busiest summit days. The stats usually reflect the time period for best weather and conditions each year. The busiest summit day varies year to year. It was June 20th in 2010, June 7th in 2009, and May 30th in 2008.

That's not necessarily true. It only means that the conditions were good on that particular day. I was one of those who summitted on May 30th, 2008. So many people summitted that day because the weather had been bad up high for more than a week before, so there was a huge backup of climbers waiting at higher camps. If I were to climb WB or West Rib again, I would start early May, same as my first trip.

Muddeer wrote:

Alpinist wrote:The annual mountaineering reports for Denali include statistics on the busiest summit days. The stats usually reflect the time period for best weather and conditions each year. The busiest summit day varies year to year. It was June 20th in 2010, June 7th in 2009, and May 30th in 2008.

That's not necessarily true. It only means that the conditions were good on that particular day. I was one of those who summitted on May 30th, 2008. So many people summitted that day because the weather had been bad up high for more than a week before, so there was a huge backup of climbers waiting at higher camps. If I were to climb WB or West Rib again, I would start early May, same as my first trip.

You must have walked right past my tent. We were camped nearest to Denali Pass next to the snow trail... I summited on June 1, 2008. The 30th was a rest day for us.

What's the Muldrow Glacier like in... August? I have two weeks off at the end of August and wanted to climb one of the lesser peaks after walking in from Wonder Lake. We were thinking Silverthrone's west face (so, not the north ridge); are crevasses / avalanches going to make it impossible (or not much fun)?

FYIW, Guide Dave Hahn told me last week as we descended together (on separate teams) that he had summitted 20 out of 26 times - all in late season (summit in July). A 76% success rate compared to an overall 50% for all expeditions throughout the season.

That said, we were part of 6 teams composed of both commercial and private who all sat out a week of high winds at the 14 and High Camps preventing any summits from early July 8 (?) to a mass exit of 50 climbers on July 18th. The lower glacier was mushy with many exposed cracks making the retreat slow and tedious. But it was warm!

Hey Alan- you guys did manage to hit a serious stretch of poor weather, which can happen at any time on Denali.

I've started up Denali in every week of the season from May 1 - June 26th over the years and have watched weather trends on the mountain for the past 18 years in the hopes of determining when the "best" time to climb might be. I've not seen any benefits to any time of the conventional season that create a compelling reason to choose one time over another.

ExciteableBoy was on the right track, in my opinion, but I'd say there are three sub-seasons:

Early (before May 7):
-colder (in the last few years, but not from 1998 - 2003 -ish)
-less snow up high
-probably windpacked/blue ice above 15,000'
-fewer people
-not sure the weather is any more or less stable
-you'll need to build your camps, but this isn't necessarily a bad thing...
-lower glacier may or may not have any lower crevasse hazard (really depends on the year!)

Mid (peak) season (May 7 - June 10):
-generally warmer down low, getting HOT as you get into June
-snow will start falling up high and can be considerable by late May, even to the point of delaying your move to high camp due to avvy hazard
-the majority of climbers for the season will be on the mountain (historic peak week starts +/- May 21- with 275 climbers one year!)
-mixed bag of weather, like always up there
-you might move into camps, saving effort, but the camps might be gnarly...
-lower glacier is generally in good shape, but not always!

Late season (after mid-June):
-Can be very hot up to 14K and can rain on the lower glacier
-it can snow a lot up high, making for great travel, if you're not breaking trail, but also avvy hazard
-fewer climbers, but many more than in April
-mixed weather
-generally lots of camps to choose from, so pick and choose
-lower glacier can be a minefield or can be in decent shape. You might need to wait a day or two for a freeze before traveling to KIA

The human variable is something to definitely consider. First of all, wrap your head around the fact that the West Buttress route is not a wilderness experience unless you head up in April. Embrace the social aspects of all the other climbers, as you are all in it together.

If 200+ climbers fly on in a given week and you have five days of bad weather, they'll get stacked up somewhere. We've seen teams turn back on summit day because they were too far back "in line" on the Autobahn, and it would have taken them 3-4 hours to climb to Denali Pass, a 1.5 - 2 hour jaunt.

Guide friends really like the early season time frame, but you need a really good day to summit, as it can be really cold up high. It's not ALWAYS cold up there, and we had a team summit from the north on May 1 a few years back, on a relatively warm day due to an inversion that settled over the mountain.

Later is better if you want to ski on the upper mountain. This only pertains to making turns, as capable skiers should consider traveling on skis at any point of the season.

When considering advice, I'd only caution you that anyone can have a relatively easy or hard time or two on Denali, and come away thinking that all the hype is just that (easy or hard). Folks who have seen the mountain in all its conditions might have different opinions on aspects of the experience.

To echo Jesus above- go do it! It is a beautiful, amazing place that anyone with a love of big, cold mountains needs to check out.

Ultimately- have fun up there!