Weather plays an important role in gaining honour and getting your population quickly. Bad weather can cost you thousands of honour in each of your villages and hinder your ability to build up population quickly. You can use blessing to counteract the negative popularity you receive from bad weather but it can be costly in terms of faith points especially if you have multiple villages in multiple parishes.

Weather Event Popularity Effect
Storms - 30
Heavy Rain - 24
Rain - 18
Showers - 12
Drizzle - 6
Overcast 0
Break in the Cloud + 6
Sunny Spells + 12
Fine Weather + 18
Bright Sunshine + 24
Heatwave + 30

Weather Time

As you can see here the time left for a weather event is displayed in the events panel. Weather does not change every single day and as you can see here there is 2 days and nearly 5 hours of bright sunshine left. You can use this info to plan how you will maximise the weather. What I mean is during times of very good weather you should probably focus on making honour and filling your vassals with troops as your population will rise faster.