Altocumulus clouds are mid‑level clouds that typically form between 6,500 and 20,000 feet. They’re made of water droplets, not ice, which is why they have that soft, textured, almost cottony appearance.

🌡️ They appear when:
• A layer of moist air rises and cools.
• That layer encounters a stable layer above it, which stops the rising motion.
• Small pockets of rising and sinking air create the repeating pattern — the ripples, rows, or “fields.”
The air then spreads out horizontally, forming patches or sheets.

📐 Why they form in patterns
Altocumulus often show:
• Rows
• Rippled textures
• Evenly spaced patches
This comes from gravity waves in the atmosphere — not the cosmic kind, but atmospheric waves created when air is lifted, sinks, then lifts again. Think of it like ripples on a pond, but in the sky.
Those waves create alternating zones of:
• Rising air → cloud forms
• Sinking air → cloud gaps

🌬️ What they usually signal
Altocumulus are classic transition clouds. They often indicate:
• A change in temperature aloft
• A weak front approaching
• A shift in atmospheric stability

Not necessarily storms — just change.

In winter, they’re especially common when the atmosphere is reorganizing itself after a cold night or ahead of a mild disturbance.

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The weather was going from 65 degrees yesterday to an anticipated 30's tomorrow, with a day today in the upper 40's. Rain is excepted later today, followed by light snow overnight.