English: A cold snap swept across much of the United States in the opening days of November 2023. While temperatures in the Northeast plummeted sharply and the first frost of the season chilled much of the Mid-Atlantic, parts of the Central and Southeast also experienced unusually cold conditions.

The winter-like blast combined with strong winds and warm sea surface temperatures to create beautiful clouds across the Gulf of Mexico on November 1, 2023. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this true-color image of the chill-induced cloud streets on that same day.

Cloud streets—long parallel bands of cumulus clouds—form when cold air blows over warmer water and a warmer air layer (i.e., a temperature inversion) rests over the top of both. The water gives up heat and moisture to the cold air above, and columns of heated air naturally rise through the atmosphere. The temperature inversion acts like a lid, so when the rising thermals hit it, they roll over and loop back on themselves, creating parallel cylinders of rotating air. As this happens, the moisture cools and condenses into cumulus clouds that line up parallel to the direction of the prevailing winds.