Interlaken to Jungfrau

I don't think so. You can usse the schedules at www.rail.ch to figure it out, but basically the train up from Interlaken takes 2 hours or a bit more, depending on which one you catch.

The very earliest one you could catch leaves Interlaken at 14:05, 5 minutes after you arrive. You would barely have time to stash your luggage in a locker (do this in Lauterbrunnen as you won't be returning to IL). This route gets you to the top at 16:20. The very last train down leaves the Jungfraujoch at 17:45. So IF everything worked out (meaning you actually caught that 14:05 train from Interlaken) you would have a little over an hour at the top. Not worth it for what it costs.

That idea will only work if you make the 2:05 pm train to Lauterbrunnen. Otherwise, it will be 4:00 when you reach Gimmelwald, and by the time you find your lodging and check in, and return to the cablecar station, you would miss the 4:30 and have to take the 5:00 pm cablecar, which doesn't leave much time for the top.

Why rush around? I don't know how far you will travel that day, but I would think you would like to walk around a bit; see Gimmelwald or walk up to Muerren, or maybe down the trail toward the Kilchbalm, as far as the bridge by the waterfall.

I also remember reading that the clouds are more likely to settle in later in the day. We went early in the morning and it was glorious - and definitely something you don't want to rush.

The first train up is cheaper, too.

Use the same afternoon for cable car to First (from east end of Grindlewald) -- best view in the world with the sun on the north face of the Eiger.

thank you all so much for responding. Unfortunately, we didn't plan enough time in Gimmelwald. We are taking the train in from Munich on Monday and then we go to Lucerne on Wednesday. We hope to maximize the short time we have.Probably a lot will depend on the weather- again, suggestions welcome and many thanks- Annemarie