Four Corners/Durango

I've been through all those areas many times. As others have said, the later in spring you go, the more stable the weather should be. July typically has lots of rain/thunderstorms which can show up unpredictably. Flash floods are always possible even with blue sky above. Because a large part of the area is open range, (wildlife on the road) I never travel at night.

Gusting winds (crosswinds especially on bridges and passes) ARE NOT your friend, especially towing a trailer.

That said, those areas are stunningly beautiful when the weather is favorable. IMO, Zion, Bryce Canyon, Grand Canyon, Chaco Canyon, Carlsbad Caverns, Petrified Forest, Lake Powell, etc. are must see's but probably not possible in a single 1 month trip.

IMO, daily (sometimes hourly) weather reports ARE your friend.

Chum lee

I had a house in Durango for 13 yrs. The weather around Durango, CO/Farmington/Bloomfield, NM will be ok in March/Apr. Durango is 1000ft higher than Farmington and you have to go over a high plateau to get there which is where most of the snow will be. Last March Farmington was mostly in the 50-60 daytime and upper 20-30's at night, zero snow. Durango was close to the same (5-10 Degrees difference) with three days of light snow. There may be colder or even warmer weather in 2021. Just watch the forecast. So if you stay south of the CO line and only drive up to CO for day trips you should be ok. US 491 from Gallup (I-40) up to Shiprock (US64) is not closed although it does go through the Reservation which is closed to visitors. Watch for livestock on the road since there are open range areas.

Late March early April expect snow, probably the heavy wet stuff... and lots off it. I wouldn't if I were you.
Good luck!

:C

Yeah,I have to do this trip in the summer time. Thanks for the feedback, I appreciate it.

Some of the heaviest/wettest snows in Colorado are in April. Weather could be 70 degrees or 25 with snow. May would be a much safer chance of good weather.

I have been through through those areas a couple of times. The last time was very recently. Plan on the possibility of encountering snow. I did when traveling that area in early April a few years back.

The Navajo Nation is closed. Reopening by March or April isn’t in the cards. See...

https://navajonationparks.org/