Article: The first place to start is with your local weather. Turn on the local forecast or go online and look up the day's temperature. Be aware of any inclement weather and listen especially for excessive heat or cold warnings. Take note of the temperature if you have an outdoor thermometer. This will give you some idea of the conditions outside. But keep in mind that it doesn't give the whole story: thermometers record the air temperature. They do not register wind chill or heat index, which make it feel colder or warmer than the actual air temperature. Extreme cold can lead to hypothermia, when the body's natural temperature gets too low, or frostbite. The Canadian Pediatric Society recommends that children play inside in temperatures under -25C/-13F However, this is the absolute limit when the skin begins to freeze in only a few minutes. The state of Oklahoma recommends that children play inside when wind chills fall below 10F. However, kids need to come inside for breaks every 20 to 30 minutes when the wind chill is below 32F. In the United States, the National Weather Service will issue a wind chill advisory or warning when wind chills are low enough to pose a threat to human life. If your area is under such a warning, you should definitely keep your kids inside. Very hot conditions can put children at risk of heatstroke, heat exhaustion, burns from hot object like playground equipment, sunburn, and excessive thirst, especially during active play. Have kids stay indoors when temperatures are over 35C - 40C/95F - 100F and wait for it to cool down. If your kids are active, or if you live in a warmer climate, it is a good idea to limit play or exercise to cooler periods in the morning or evening. Avoid playing in hot weather between 10am - 4pm. The National Weather Service issues excessive heat warning and advisories whenever it is hot enough to be hazardous to human health. You should keep your kids inside if your area is under such a warning. Many schools have rules on what temperatures are suitable for outdoor play, and hold indoor recess if it becomes either too hot or too cold. Learn what rules your school has and try following them at home; if outdoor recess is cancelled, you'll know the temperature is dangerous.

What is a summary?
Check the local weather forecast. Keep children indoors in very cold conditions. Keep children indoors in very hot temperatures. Follow your school's guidelines.