Rainbow as a weather indicator

A rainbow appeared in the sky on Wednesday shortly after sunrise, sparking different interpretations. Some saw it as a reassuring sign, while sailors historically viewed it as a warning of approaching rain or storms.

Formation of morning rainbows

The phenomenon occurs when sunlight reflects off water droplets during a shower. In the morning, the sun rises in the east, so for a rainbow to appear, the rain must be in the west, indicating the storm is moving toward the observer, not away from them.

Rainfall across France

A disturbance passed through France on Wednesday, bringing heavy rain across most regions. Rainfall reached 15 to 30 mm in many areas, with over 100 mm near the Mediterranean, and snowfall began in the Alps at 1,500 meters above sea level.

Persistent drought and wet conditions

Despite recent rain, 84% of France was still under a decennial drought as of September 20. The ground remains saturated, and new intense rainfall episodes are expected until mid-December, according to Météo-France.

Mediterranean weather patterns

This rainfall is part of a recurring pattern, with Mediterranean episodes typically occurring between September and mid-December. These events are linked to the warm sea temperatures and are expected to happen three to six times a year on average.

Future weather outlook

Météo-France predicts warmer-than-normal temperatures for the coming weeks, with increased humidity in the west. However, precipitation forecasts remain uncertain, and caution is advised, especially near the Mediterranean.

Importance of weather vigilance

A rainbow observed at dawn does not signal improvement but serves as a reminder of potential rain. This has been a long-standing warning for sailors and remains relevant as the ground remains waterlogged and heavy rain is still possible.