Hi, Iris -

Congratulations on what sounds like your first grow! Whatever you do, do NOT let those buds get wet at this stage of the game! That is simply ASKING for them to turn to mold, which can happen easily anyway in humid weather. The rain will also wash away the trichomes, so even if your pot survives, it won't be anywhere near as potent as if it had undergone a "dry" flowering.

Try to construct some sort of cover or awning that will completely protect the plants from the rain water hitting them directly. If you must, bring them into a brightly lit area in your house/apt. until the storm clears. Artificial lighting might be of help, but it's a little dicey when the girls are used to natural sunlight and are suddenly subjected to the different spectrum of indoor lighting.

Luckily, I have an screen-enclosed back porch with an awning, so if it looks like we're due for some precipitation, I make sure that's where the plants are. If you have an area like that available to you, I would definitely use it.