A storm is likely to come when:
deciduous trees flip their leaves due to wind direction
birds fly low in the sky, and go quiet
there’s a southerly wind (in the US)
there’s a red dawn in the east
layers of nimbus clouds move in opposite directions
the morning grass is dry of dew
an earthy scent rises from the soil and flowers
pine cones remain closed
a halo rings the moon at night
nights are warm in winter (cloud cover insulation)
smoke swirls and descends, instead of a steady rise
Remember, low pressure brings wet weather.