Logging rainfall with Python

It looks like you are continuously setting your rain to 0 in your while True: loop.

Edit: Try something like this for your loop.

def timed_loop():
    rain = 0
    timeout = time.monotonic() + 3600   # 1 hour from now
    while True:
        if time.monotonic() > timeout:  # break if timeout time is reached
            # You place your code here that you want to run every hour. 
            # After that the loop restarts
            rain = 1  
            time.sleep(1)          # Short sleep so loop can be interupted
            continue

Edit 3:

With the following code you can record button presses over a specified amount of time.

import time

def bucket_tip_counter():
    recording_time_timeout = 3600  # Amount of seconds you want to have the timer run
    recording_time = time.monotonic() + recording_time_timeout
    button_timeout = 1  # This timeout is here so the button doesnt trigger the count more then once for each trigger
                        # You have to modify this to your needs. If the button stays activated for a few seconds you need to set the timer accordingly.
    count = 0           # Sets the counter to 0 at the start
    button = 0          # Here you need to replace the 0 with the GPIO pin that returns True if the button is pressed
    while True:         # starts the loop

        if button:         # if button gets pressed/bucket tipped
            count += 1     # up count by one
            time.sleep(button_timeout)  # wait specified timeout to make sure button isnt pressed anymore

        if time.monotonic() > recording_time:  # If the recording_time is reached the loop triggers this if condition
            print(count)   # print count
                           # Here you can also place code that you want to run when the hour is over
                           # Note that the counter wont start back up until that code is finished.

            count = 0      # set count back to 0
            recording_time = time.monotonic() + recording_time_timeout  # Set a new timer so the hour can start anew
            continue   # restart the loop

        time.sleep(1)  # small sleep to stop CPU hogging.