Road Trip to Meteora from Athens tomorrow

I certainly do not have experience with Greece in December. Having said that when we visited Delphiin May I can confirm that is is way up a mountainside and there were closed ski resorts in the area. That means snow. Driving in the mountains in snow is not the least bit appealing.
Frankly you plan to do both Delphi and Meteora in two days even in the summer is a whole lot of driving. The snow is probably doing you a favour by having you drop Delphi for Meteora. The drive to Meteora is about 5 hours. About three quarters of the drive is done on a big toll highway with no elevation to speak of. The road cuts of towards Kalameka but I do not recall much in the way of elevation until you actually arrive in Meteora. It is definitely up in the mountains. My guess is you might find some snow up there. The good news is the Monastery loop road isn't very long. The photo opportunity at the Monasteries in snow might be enough to tempt me to do the trip.

You might want to ask some of the staff at your hotel in Athens what they know about driving and snow conditions on the way to Meteora.

Thank you stanbr. This is very helpful. Meteora has no snow this week. And it is snowing in Delphi. I will drop Delphi.

I will ask at the hotel about getting to Meteora avoiding Delphi or higher elevation. Am from bay area, and we always avoid driving to Lake Tahoe truckee area while it is snowing!

I will ask at the rental counter at the Piraeaeus port whether they can rent me a snow chain .

thanks

The route I was suggesting does not go any where near Delphi. It is a toll road though. On this map it is listed as the best route.
https://www.google.gr/maps/dir/Athens/Meteora,+Kalabaka/@38.849685,21.622095,8z/data=!3m1!4b1!4m13!4m12!1m5!1m1!1s0x14a1bd1f067043f1:0x2736354576668ddd!2m2!1d23.7275388!2d37.9838096!1m5!1m1!1s0x13590faee8327f39:0x7127add4d8bc32ff!2m2!1d21.6305896!2d39.7217044

Thanks stanbr. Currently the map/route you suggested on google maps shows 4 hours(356 km). Apparently the route from
Delphi to Meteora is closed on google maps(to open at 10am). It looks like E75 all the way from Athens. The route via Delphi was e65/3.

For the toll, do I need some transponder device on the rental car, or would paying currency/change by Euro would be good. Are these tollbooths manned by people or throw coin/currency or transponder.

thanks

toll booths were populated by people as I recall.