Mt Whitney Zone Forums General Discussion Seeking opinions on best month to hike the JMT

Hi Folks -
I'm looking for experience-based opinions on the best month, weather-wise, to plan a section hike of the JMT.
I plan to enter via the Bishop Pass Trail and exit at The Portal.
I'd like to do this in August/early September - trying to avoid mosquitos.
Thanks,
Shane

You know mosquitoes monitor the Zone, too!

September is my favorite month in the Sierra but it can get a bit chilly...like single digit chilly.

I was told that third week in Sept is when the weather "changes". Of my three Sept trips, I found that to be accurate. The law of averages suggests that this cannot be true all the time of course.

I tend to favor hiking the first few weeks of July because it tends to be less likely to be stormy. But Sept. is similar. I don't recall having problems with mosquitoes on any of my JMT section hikes, and nearly always hiked in July.

I hiked north on the PCT out of Tuolumne Meadows years ago, and we expected (and encountered heavy) mosquitoes. We were prepared, though: mosquito head nets, and a spritz of high % DEET repellent back of the hands and any thinly-clothed areas. When mossies were heavy, we just hiked on until we found a drier (and mosquito-free) spot to camp.

Steve's July theory got shot all to hell this year (2014), as I recall. I went (through-hike) in August last year (2013), did not have mosquito one, and had some rain on 5 days out of 23. Four in a row (typical late summer system) just after mid-point, then one more on second to last day, August 28 or so.

What you are describing, however, is a pretty short trip. I would slide it in there maybe first week of August to optimize best weather after mosquito season.

Whitney trips totaling about a month worth of days I have rained on a total of 5 minutes. However, there was a stretch where every Sierra trip I went on it rained...rain was rarely in the forecast.

Also to shoot Steve's theory full of holes, my worst rain in the Sierra was in July during a trip to the Pioneer Basin. I was after big winter and the skeeters were insatiable. This particular weekend Whitney got hit with a Biblical proportion storm.

If it is a dry winter the skeeters are not as bad and are gone earlier than after a big winter.

Thanks all - Happy New Year!

I've done the JMT in June, July, August, September and plan to add a few more months to that list.

Of the above months, my favorite for weather, bugs, water availability is August, but very crowded, very dusty, lots of smoke from fires possible, no snow, no flowers, scenery getting bland compared to July. Also, days are shorter, which for a high mile hiker makes a difference over July.

July probably the best all around, especially in high snow years. Fewer people than in August, long days great flowers and scenery, much more water (sometimes almost too much), and great alpine feel with still some snow around. Skeeters are on and off - some areas they are just insane, then in the next valley you won't have any. Last year, Bear Creek area was the only place we had real bug problems, no bugs north of there, almost none south. Weather can be unsettled, although even in a strong monsoon year, we usually only hit one or two rainy (or snowy...) days.

September - my least favorite so far. Short days, dull, brown scenery, getting very dry so you have to haul more water. No more flowers, tons of people on the trail who want to "avoid the August crowds" - I did a northbound hike in Sept and saw on average 100 people a day. Compare to about 20 southbound in any July (except Mt. Whitney trail where we saw 220 on one day). Weather stable, though.

June - in a dry year, you can do the trail in mid June, and you won't see many people at all. The more snow and deep crossings you can handle, the earlier you can start and the more solitude you'll find (except for those pesky PCT northbound hikers who come through rather early as well), but the more hard core the hike gets, especially on Mather and Glen, where snow can get you into sketchy situations if you don't know the exact trail routing and climb into the wrong slope. Almost too early for bugs for most elevations, but thick near the lower valleys. Weather much more stable than in July, but when it turns, it can still snow sometimes.