Yellowstone / Grand Teton Advice
 

Hi,

Mu husband and I are planning a 2 week trip to both Yellowstone and Grand Teton Nat'l Parks either the 1st 2 weeks of June or the 1st 2 weeks of September. I was just wondering which is the better time to go? What is the weather like? Crowds? What things should we not miss in both areas? Any and all input greatly appreciated!

The first two weeks of September is a great time to go. The leaves have started to turn enhancing an already magnificent area.
The crowds are light and the weather is fine, though it does get cool at night.
We've been there in September and mid-summer and definitely prefer September.
As for what to see, I recommend you get a copy of Frommer's guide to the two parts. We found this small, easy-to-carry guide invaluable.

I was there June 21 of 01, and it snowed so hard they closed the roads. It was gorgeous, but that might be something to consider.

We were there the first week of June 2000 and had warm, sunny beautiful weather! The Beartooth Highway had just opened. The crowds were very light!

We have also been in mid-July and had snow...didn't close the roads tho. I think snow is possible any time!!!

Utahtea

I would always pick early Sept. No crowds, weather almost always lovely. (Although, that's a long time to spend in just that area; have you considered adding Glacier?)

We drove the Beartooth Highway in July and there was still enough snow at the top that people were skiing. I would look into weather stats. My hunch is September would be a better time.

I have been there in late May - early June, and in early September. Both have advantages and disadvantages. If you are here too early in May, the ranger programs are not yet in full swing.

By the second week in September, the summer ranger staff members have gone back to their regular jobs.

So there are ups and downs regardless.
I would say this year that right after Labor Day might be a good time to be there.

However, you don't escape crowds in Yellowstone during good weather!!
There will still be many tour buses bringing people in to the popular sites:
Grand Canyon of the Yellowstone, the Norris Geyser Basin, the Upper Geyser Basin (Old Faithful and all the rest), and the area around Lake Yellowstone.

My favorite areas in Yellowstone are as follows:

1. The Grand Canyon of the Yellowstone and those wonderful upper and lower falls. Incredible sight.

2. The Upper Geyser Basin, including thse geysers: Grand, Castle, Riverside, Daisey, and Old Faithful. These 4 are somewhat predictable, but the eruption time window is as long as 4 hours.
Grand is worth the wait. It is spectacular if you can watch it do its thing by the light of a full moon.
It is the one geyser in the park that draws rounds of applause from the viewers. I am not joking!!

3. Lone Star Geyser. Requires a hike along a flat trail part of which is an old road. The geyser itself is isolated and erupts every 3 hours or so. I take my lunch, take a rest under the trees, and wait. (bring something to lie on and enjoy the wait).
4. The Fountain Paint Pots and Great Fountain Geyser. Seeing Great Fountain is difficult because it is a little unpredictable. You must be prepared to wait, but it is worth it. I had to try several times before I finally was fortunate enough to see it erupt.

Slight amendment. Grand Geyser is spectacular - period. It is even more thrilling under the light of a full moon.

It was more than worth going out at 2 am!!

Believe it or not, but we were hardly the only viewers. Dedicated Geyser Gazers are there at all hours because Grand Geyser is just that - grand!

(That is what vacations are all about!!)

We have been in both months -June 2004
September 2005. There were definitely comparisons. The things we enjoyed most about the June trip was the snow still on the mountains which made for wonderful pictures and the green valleys with the beautiful wildflowers in bloom. June also made for more abundant waterfalls due to the run-off of the spring thaw. There also were less crowds at that time for us because I don't think that the family vacation season had gotten into full swing.
September - The aspens were so beautiful, along with the vibrant colors and beauty of the drive up from Salt Lake City.
The bugle of the elk was also a unique sound to hear at this time of the year.
There was no snow on the mountains - and we didn't see one snowflake! (I'm sure it was just a timing thing...)
We also experienced more retirees on the trip in the fall. (as our children - in their 20's said - a lot of geezer geyser gazers)

We always enjoy our trips through Lamar Valley to Cooke City and the drive up the Beartooth Hwy is a MUST.
Our children said this was one of the best things of their trip - seeing the mountain goats.