Make a copy of this layer and blur the copy out, making use of the next selection: Filter - Blur - Smart Blur.

fairy tale - rainy day - 
photo effects

Change the layer's type on Darken this time and merge down the layers (ctrl+e).

fairy tale - rainy day - 
photo effects

Insert on a new layer a picture having portrayed on it a water reservoir:

fairy tale - rainy day - 
photo effects
   


Choose all the options shown here (Free Transform, Layer Mask and Gradient Tool) and place the layer above the picture to have the impression that the rain is falling out of the reservoir:

fairy tale - rainy day - 
photo effects

Apply to this layer the command Image - Adjustments - Gradient Map to select the same colors we have on the next picture:

fairy tale - rainy day - 
photo effects