The rain is not just happening around Elaina's farm, it is also happening around the town. The soldiers are already alerted to this phenomenon where the Merfolks are suddenly surfacing on the land and everyone is afraid or curious as to what the merfolks are doing and why are they suddenly appearing like this out of nowhere.
As for Elaina, despite the warnings she received from the doctor, grabs her sword and readies for anything that will happen. She had a bad feeling about this new situation.
The Harvest Goddess seems to realize something as well and before Alessa can think of what to do. She returned to her realm and hid Mier there in hopes that the merfolk arriving would not see her.
"Alessa, you need to hide as well. You are hiding from them, right? Then go back to my realm and wait until the situation passes by!" the Harvest Goddess ordered the shocked Alessa.