Related Clues:

• Sign from above
• Thunderclouds, for sure
• Writing on the wall, e.g.
• Mysterious sign
• An eclipse, some think
• Foreshadowing
• Sign of the future
• Sign to heed
• Advance information
• Sign to interpret
• What a prophet reads
• Divine sign
• Soothsayer's observation
• Auspice
• Sure sign, for some