Hi, I am planning a trip for late in 2019, and will land/direct flgiht, in Frankfurt airport and train to Nuremburg. Then travel to Vienna by ship, and either will fly out back to US after several days, from Vienna/Amsterdam/Atlanta or Vienna train to Frankfurt direct to Atlanta. Since the weather will be rather "iffy" in December of 2019 (not excited about extra flight segment in Winter), and since I think it would be less expensive round trip from Frankfurt, I am wondering how long and how complicated the train from Vienna to Frankfurt airport would be? Are there direct trains or does one change trains? I know I need to check the Bahn, just curious. Thanks for your input ahead.

Yes, there are direct trains from Vienna to Frankfurt; our children take them for athlete events to and from Frankfurt. The travel time is about 8 hours.

On Bahn.de I picked a random Wednesday in mid-December. Direct train (4/day) no changes, 6 hours 21 mins , 99.9 euros in 2nd class.

Most nonstop flights from Germany to the US depart in the AM hours.
Unless that flight to Atlanta was an exemption from that rule, you'd need another night in Frankfurt just to catch your return flight.
Or take the overnight train (NightJet) leaving Vienna Central at around 9pm, arrive Frankfurt Airport station 6am (no changes).

If your prime concern is the weather... I'd rather trust Vienna Airport to deal with adverse weather than German Rail ;-)
Aside from joking: When you book the open-jaw flight (US> FRA; VIE>AMS>US) on one ticket, the airline(s) is responsible to get you back to Atlanta by whatever is necessary. The train to plane connection you think about is not protected.

First direct train leaves Vienna weekdays 11am or so but you can leave on several earlier trains with one simple change of trains- see www.bahn.de/en - German Railways site and book there from 79 euros cheapest for one change trains - 155 full fare so book early. For lots on that see www.seat61.com; BETS-European Rail Experts and www.ricksteves.com. You may look into flying Vienna to Frankfurt probably just as cheap. The overnight train could be good - save money on a hotel.

https://www.nightjet.com/en/

Night trains Vienna-Frankfurt Flughafen (Airport)

official site

thanks all for the into. I sort of like the idea that the airline is responsible to get you on flight per comment by Cowboy. However, I think I will try to get the direct flight to Frankfurt for son and myself with FF miles. I would not have enough FF miles for return. So, if I just booked our two tickets from Vienna/Amsterdam/Atlanta, would that same thing apply, to get us to plane in FF without extra fees if held up with weather? I think that open jaw flight makes the most sense, but need to check cost for this. Does the train get held up very often in Late Dec/Jan? Thanks again.

Not sure if I really understand the plan.. but I give it a try anyway
When you book any flight that involves one or more connections on "one" ticket, this/these connections are protected.

I didn't mean that the trains break down regularly, but it's a bit of a hassle IMO to take the train from Vienna to Frankfurt, spend the night there, and fly back home next late morning.
If you lean towards the train to plane option, though, you could also check this:
ATL > FRA nonstop as planned.
Return.. train from Vienna to Munich (just 4 hrs), see a bit of Munich, fly nonstop Delta next day Munich > ATL.

Instead of backtrecking to Frankfurt (longer train travel, and you've been there before) you'd see another city, if only somewhat briefly. But better than nothing. Unless it was much more costly than returning from Frankfurt or via AMS.

Thanks all, I've made up my mind.....use my FF milesfrom ATL to Frankfurt for two tickets, fly back from Vienna to Amsterdam to Atlanta/pay for tickets, and hope for decent weather, as I hate flying in snowstorms in and out of Germany as I've done before. Had some scary flights in December, one to "test" the automatic landing electronics which was a hard landing, but on Lufthansa, so maybe better on Delta, but then probably wishfull thinking. Thanks again.

For whatever consolation or planning help this might be, our son has been stranded at Schipol (AMS) due to weather on a few return flights to the US from Vienna. If your connection looks in trouble, book a hotel as soon as possible (DS says the Hilton is nice).

And I know this is a year out, but if you're on the 0655 from VIE to AMS you'll need to reserve a driver; the City Airport Train and public aren't running early enough to get you to the airport on time.

thanks four fortravel. I'll save this if I can figure out how to do it.

Frankfurt is much maligned but in many ways is a fascinating city - sure it lost its old-world looks in WW2 but still retains bits of charm and world-class museums - I'd stay there day of landing and bop around. Or take the overnight train and spend your last day there - great shopping area.

Sue, either ask your concierge to reserve a car, or use the Airport Driver service; that way you will charged the flat rate versus the per kilometer/time rate.

Not to contradict fourfortravel's suggestion but for the sake of completion:
While the trains to the airport won't run in the very early morning hours, the Vienna Airport Line buses do.
https://www.viennaairportlines.at/en/
Nevertheless, I would go with fourfortravel's advice and let your hotel book an Airport Driver service. It should be around €30 flat fee, and I haven't yet seen a hotel in Vienna which would not advertise or offer that service, not only the high-end residences.

When calculating the time you need to be at the airport prior to departure, keep in mind that Vienna is a highly efficient airport and that your flight Vienna-Amsterdam is still within Schengen so there won't be passport control in Vienna just regular security screening.
The bottleneck may be how quickly or slowly KLM will take your bags at check-in (if you need to check bags), but so far security in Vienna has been a matter of zero to ten minutes waiting time.

Cowboy1968, thanks for adding that. I saw that, too, but depending on where the OP will stay there may not be public running early enough to reach one of the Bus Stops, and dragging luggage on a cold December morning (in the dark) to a Bus Stop would be a miserable way to end a holiday.

We used the Airport Driver last month, and the one-way flat rate was €36 for two persons and two medium cases. Just FYI.

Thanks cowby and four for travel, lots of good info here. Palen, been to FF quite a few times with friend living in Wurtzburg. Will fly back out from Vienna. Thanks all. made notes of all of this.