I have a few figs ripening, and the temps tonight are supposed to dip below 40F.

Will the cold hurt the ripening figs?  I can put the trees into a shed for the night.

Thanks!

Good question.  We got down to low 40s last night.   I put a few of my tree in the garage.  Good thing I did because we got a lot of hard winds throughout the night that I didn't expect.

Here in NH I don't bother moving them in unless it is going to hit 32F.
We have been very close to 32F several times and leaving them out doesn't seem to stop normal ripening , just slows it down.
If it is easy to move them I'd do it , but I haven't bothered and so far still getting plenty of nice ripe figs from RDB , LSU Scott's Black , MBVS , Natalina , Gino's ,Vista, LSU Tiger ,Black Bethlehem, Atreano , Conadria, Latarolla, Maltese Falcon, Nero600m , Valle Negra, Vincenzo, Large Negronne.
It is supposed to hit 32 tonight here , so I might move a few in that are easily moved. 

Phil, I agree that is a good question.  A month ago we had a light frost while I was out of town, resulting in slightly damaged  leaves on most all my trees. The figs have still been good, I think it caused a handful to drop but overall not a mass abortion of immature figs. I have had several nights of frost since then and not all my trees are easily mobile so they have been left out to tough it. They are Petit Negra, Hardy Chicago, Malta Black, and RdB. These trees are holding out fine and slowly ripening figs, the key term is slowly. We get upper thirties to low fourties every night now and the pots/roots stay pretty cool which is causing the ripening process to take twice as long as it did a month ago. The figs are still good(better than no figs!), but on average they are way less juicy, less sweet, and the skin is more tough. I should add that the RdB hasn't ripened any figs recently because they are all figs that were put on late(zero have dropped), the first main crop figs ripened forever ago, but there are some I can see which are beginning to swell.

Not sure what the combination of requirements is, but in my experience, late fall ripened figs are never what they would be in August and early September. I think that day time temps below 80 are insufficient for good ripening, regardless of the time of year. Shorter days, and cooler nights may be part of the issue - don't know. Figs ripened in Central California, such as the ones at USDA/UC Davis typically ripen in weather that is 90-105F in the day time but quite possibly in the 50s at night. Maybe the longer days offset the cooler nights - don't know.

When I was as Wolfskill this summer, on August 19 and 20 the days were in the low 90s and nights high middle 50s, and that was more or less at the peak of the ripening season. That would seem to indicate that day length is more critical that night temps.

Another issue of night temps is what signals are being sent to the plant: 40s and 50s at night would probably signal "fall" and "go dormant", and probably stop sending signals to use resources for fruit, so the sugars may go to the roots rather than the fruit. Shorter days mean less photosynthesis, which means less sugars and flavors are being made by the plant.

The fruits still "ripen" (which actually means produce viable seeds to guarantee the next generation) but a plant that is in a "hurry" before dormancy may not put as many resources into making a tasty fruit (our idea of ripening) as it would earlier in the season.

Thank you all for your replies!

Looks like high 30's aren't that much of a concern.  I will leave them out. 

I am hoping to at least try one from Panachee.  The figs have been on there in stagnant stage since about mid-July, and a couple of them just swelled.  I realize they won't be as good as heat ripened, but some figs are better than no figs!

Thanks again!

If you're worried you can put plastic sheeting over them.   If you're really worried you can add in Christmas lights.