Which of the following is likely a sign that it will rain soon?

1. Rising temperature

   No. A warm air mass moving into your area might bring rain, but it also might bring sunny weather. Rising temperature by itself is not a good indicator of rain.

2. Decreasing humidity

   No. The humidity at ground level does not play much of a role in the formation of rain in the clouds. Just before it rains, the precipitation could cause the humidity to increase, but it would not cause it to decrease.

3. Wind out of the west

   No. Any weather front moving in from the west could cause winds, even if it was bringing clear, sunny weather.

4. Falling barometric pressure

   Yes! Low pressure fronts are commonly associated with rain and storms, so falling barometric pressure is a good indicator that rain may be on the way.

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