Firefighters in Oklahoma are warning owners not to leave bottled water exposed in their cars.  The water, if struck at the correct angle by the sun, can act as a magnifying glass, focusing the beam.  The resulting beam can be hot enough to cause a fire. Although the likelihood of this happening is slim, it did occur in Idaho in 2017. So take the water bottle with you, or place it under the seat or other area not exposed to the sun.

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