What does this sign indicate?

• The road ahead is closed during wet weather.
• Drivers should increase their speed to avoid slipping.
• The pavement ahead has been grooved to reduce slipperiness in wet conditions.
  Explanation:

  "This sign is used to inform drivers that the road surface has been intentionally grooved to improve traction and reduce the risk of vehicles slipping during or after rain."
• Wet weather is expected ahead.