I'm guessing that for this scenario, the temperature is supposed to be more or less the same, and there is reasonable food production possible from diffused sunlight. The idea is about the specific effects of not being able to see much of the sky through cloud cover.
Many sciences might not be directly affected by the cloud cover. Before balloons or heavier than air flight are developed, there still could be development of ballistics. Ocean navigation wouldn't advance, at least until radio beacons or some other non-celestial method become available. The moon and sun might be inferred both due to tides, and because of the changes in light levels. Scientists would notice that weight varied between equator and poles. The
Focault pendulum would still work. So, they might be able to determine the Earth's rotation. I could imagine where scientists might infer a universe consisting of the Earth, moon, and sun, up until the time they could see above the clouds.