Yes, look for the GFCI outlet.

If you are unfortunate enough to have this person's electrician, it may even be outside! Assuming that dumb and dumber didn't wire your kitchen, I'd look for the GFCI in your kitchen.

Generally, cold weather doesn't cause electrical outlets to fail.

Soooo, what I missed when looking at the electrical panel is that the 2 breakers for the outlet strips have built in reset buttons. So I hit those and then switched the breakers off and on again and they are working. It was a bit confusing b/c the electrician told me over text that the outlet strips have reset buttons on them, but they don't. I went over those strips about 5 times, wondering if somehow I had missed a button, but no, there are no reset buttons on the strips. They are on the actual breaker switches. I feel a little silly for missing them, but I was also led a bit astray by the mythical outlet strip reset buttons . . .

No, they are outlet strips. It is definitely odd. I think the microwave was in use and the radio was on, but that was it. It's not like we had all the things plugged in and turned on. Very strange.

Glad you figured it out. I had something similar when I plugged in a plug and accidentally hit the reset button.

The microwave just sits on the counter and is not on a separate circuit. I wasn't 100% sure where on the counter I was going to put it until close to the end of our remodel. But here's a question. A day or two before the trip happened, we started having trouble with the MW. It was both arcing and making that awful electrical noise (loud "whomp" sort of). Could whatever happened to the MW have cause a problem with the circuit? And can I just say how annoying it is that this happened just a month after it was no longer in warranty?

Is the microwave that caused the recent trip the same one that was arcing, etc? If so, the problem is the microwave and it should NOT be used any longer as it has an electrical failure of some kind.

Yeah, we got a new one yesterday. Could that have caused the problem? It was on when the power went down, although it was not making that noise at the moment. I didn't realize the power had gone down until I went to get my milk from the MW and realized it wasn't hot.

Reading back over your posts, you mention no buttons on outlets, but instead buttons on the breakers.

In this case, it sounds like maybe GFCI breakers were used instead of GFCI outlets. These are typically used when a GCFI outlet wouldn't be readily accessible.

Now, building code dictates which would be appropriate - assume the inspector either approved or required this choice.

When there is an electrical fault in an appliance, current is going where it shouldn't and creates a dangerous situation. Your breaker saved you from further issue. You should not have used the microwave after the first incident. I'm very surprised that you did.

To tell you the truth, I forgot! When it first happened, I freaked out and turned off the MW, was annoyed, and went and did something else. I used it again later and it was fine. Until it wasn't again. I am glad to have those breakers. I assume they are required by code where I live. We had to upgrade our panel and it passed inspection.

Do you think the MW is what caused the trip? It was running normally when the trip happened.

It is HIGHLY likely that the microwave caused the problem when it developed electrical problems. You are lucky that the breaker tripped (as it should have) rather than something worse happening.

In the future, if something like this happens (a malfunctioning electrical item that arcs) and you're likely to forget that it did, remove the appliance from the area so that it cannot be used again and dispose of it properly. Electrical faults are serious.

Also, while arcing scares me, I have gathered that it's not always the death knell of a microwave. I have experienced it when reheating green beans, but only once in a while. In that case it was the beans, not the MW. I also read that if the MW is dirty/greasy, it can happen. Mine wasn't very dirty but I cleaned it anyway and tried it. Still arcing, and that's when I decided it was a lost cause and bought a new one.

I never understood the green bean thing, but I just googled and found this

https://www.npr.org/sections/thesalt/2016/10/03/495975189/snap-crackle-kale-the-science-of-why-veggies-spark-in-the-microwave