Rain on the Rhine

Where do you get the rain forecast from? The next days seem to be widely sunny, except moments in the afternoon.

If you like castles spend some time in a castle tour / visit. For a whole day visiting Koblenz can be an option.

I hope you have checked that you have driving permission for Germany?

Carl, I wouldn’t worry too much about the weather forecast. As Mark said, it sounds like that may not be accurate and even so, weather changes from day-to-day. However, if you have rain, there are always things to do. You can visit some castles, like Berg Eltz or other places. I loved Burg Eltz and would recommend it even if you didn’t have to find a place to get out of the rain.

Also, I wouldn’t worry too much about the driving permission. Basically that law says that if you have a valid drivers license from the US, and you’re at least 18 years old, your license should be fine. I would suggest getting an international drivers permit, however, as I think they are required in Germany. You can get them at AAA for $20.

Info: I checked with authority Federal Ministry for Digital and Transport. They confirm that German driving permission law requires IDP in the cases mentioned here:
https://bmdv.bund.de/SharedDocs/EN/Articles/StV/Roadtraffic/validity-foreign-driving-licences-in-germany.html

Thanks, Mark - good to know for sure!

Carl, when exactly will you be there? The only weather forecast you can conceivably rely on is one that is maybe 1-2 days out, and even then, that's iffy. :-) Weather is weather, and forecasts are inherently unreliable.

If I have a valid drivers license from the USA, do I need an international drivers permit in Germany?

It rained when I visited the Rhine and I did everything I had planned on doing, including hiking, doing a Rhine castle cruise, and visiting castles. Clouds add to the atmosphere and make for moody photos.

If I have a valid drivers license from the USA, do I need an
international drivers permit in Germany?

to answer this question, an IDP is a translation of your valid drivers license into other languages, so law enforcement can understand it and know your identity and authority to operate a motor vehicle. See prior discussion on same topic here https://community.ricksteves.com/travel-forum/germany/international-driver-license

nixit71, the answer is yes. German law requires you to have an IDP and your drivers license from home. The IDP translates your license to the local language.

I love the use of the word may on government websites. This is from the US State Department @ https://de.usembassy.gov/driving-in-germany/

U.S. citizens planning to stay less than a year, however, may legally
drive in Germany for up to 364 days in Germany on their U.S. driver’s
licenses.

You can compare Germany to the State Department's information regarding Austria:

A U.S. driver’s license alone is not sufficient to drive in Austria.
It must be accompanied either by an international driving permit
(obtainable in the U.S. from AAA) or by an official translation of the
U.S. driver’s license (obtainable at one of the Austrian automobile
clubs, ÖAMTC or ARBÖ).

"The IDP translates your license to the local language." - It has to be more than that. UK drivers do not require an IDP to drive in the EU.