How to make a Rain Gauge:

Step 1: Take a empty plastic bottle of any size( e.g. 1.5 litre bottle(recommended). Cut th top of the bottle about a quater of  the way down where it meets the consistent diameter.

Step 2: Remove the bottle cap and invert the upper part of the bottle as the bottom part / as the funnel.

Step 3:Place the rain gauge in an open area where it will collect rain and a place where the trees or buildings would not block the rain gauge.

Step 4: Start measuring. Measure the amount of rainfall collected every morning at a fixed time.

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                                                       how it looks like in the end.