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Wind-chill experiment

Here's how you can test whether water will freeze with an ambient temperature of 35° F (2° C) and a wind chill factor of 25° F (-4° C).  First, you need a fan since it takes a 15 mph (24 kph) wind to produce a wind chill factor of 25° F if the air temperature is 35° F.

1. Empty the refrigerator (ideally) or put the food on one shelf to allow air flow.  Take out any glass shelves or shelves that block air flow.
2. Set the frig to 35°; put a check thermometer in.
3. Set a pan of water on the middle rack.
4. Place a small battery-powered fan on the top shelf pointed at the pan of water.  A link for a $14 battery-operated fan is given below.
5. Estimate the air speed from the fan onto the water by feel with your hand.  Close the frig door as much as possible on your arm while estimating the air speed.  You probably can guess that the air speed is, say, somewhere between 5 mph and 20 mph with some confidence.
6. Calculate or look up the wind chill factor associated with your air speed estimates and refrigerator temperature.  A link for a lookup table is given below.
7. Stick a thermometer in the pan of water.
8. Check the temperature of the water until it reaches about 35°. 
9. Leave the experiment going overnight to see if the water ever freezes. 

Good luck!

NOAA: National Weather Service wind chill chart

Safety Central: $14-battery operated fan