Weather planning for trips that are months out

I’d Google the nearest airport or town that might have records. In this case:

“Jackson Hole Airport (KJAC) weather history september”

Then I would correct for altitude — gets colder when higher; possible rain shadow effect — west wind crossing n-s oriented mountain ranges, and differences in foliage density and type between place of report and destination — denser woods with more ground cover are often more humid than nearby areas.

Flexible Itinerary …. options

I guess I would try wunderground dot com, get nearest town, get nearest weather station, look at history (make sure history link is correct weather station in url)…and read skurka’s article.

https://andrewskurka.com/backcountry-weather-conditions-forecasting-methods-sources/

Andrew Skurka has a good tutorial video on this very topic.  You can find it on his site by searching “NCEI”, that is, National Centers for Environmental Information.  The NCEI site is a bit clunky, but can be figured out with some persistence.  I used it recently to look up data for a trip I’ll be taking in September, though I noticed that the current process to obtain the data is slightly different from the Skurka tutorial.

Specifically look at data for El Nino years, as this now is one. That should give you more realistic weather expectations. This is the beginning of a new climatic era.

Look at the typical weather and climate averages (sun, rain, snow, winds, .. lightning .. but also hurricanes have interrupted late AT trips in the American south), but also be on the lookout for extremes/other patterns.

Then there’s alternate plans considering right now the American NE is getting inundated with smoke which has been the case in the American West … usually.  An old Backpacker magazine recommendation was plan for 200 miles the opposite direction in case weather disrupted plans, but maybe now (for long trips)  it’s look at the other side of the country?  Planes, trains, etc..

Example 1:

El Niño is making an early comeback for 2023 that could open the door for even more extreme weather in the last part of the year

https://www.accuweather.com/en/climate/el-nino-is-officially-underway-heres-what-that-means-for-the-weather/1538335

(seeing this every from the Los Angeles Times to Oklahoma news .. so choose your geography).

Another El Niño may mean a big storm in the late spring or even early summer desert for instance.

Example 2:

Hotter weather year over year is resulting in rattlesnakes coming out early …

https://www.nbclosangeles.com/news/socal-wil-see-more-rattlesnakes-this-year-heres-what-to-do-to-stay-safe/3143146/

and likely more numbers as temps in the upper 80°F is optimal for their digestion.   So there’s keeping an eye out, but also realize overgrown trails make this a little tricky if they don’t rattle.    If ssssnakey encounters rattle you (ok, pun intended), maybe plan SoCal and Arizona trips more towards the dead of winter (taking appropriate gear and clothing of course).

We do plan alternate itineraries for local (driving) trips, but that doesn’t work for trips like our upcoming Yellowstone trip, that involve flights and advanced reservations of back country sites.

Thanks for the wunderground suggestion – I knew there was a weather site with good history, but I was struggling to find it last week!

Also thank you for the Skurka suggestion. I’ve mostly only read his food info, will start going through the rest of the info on his site.