A Wind Chill Advisory is issued by the National Weather Service of the United States when the wind chill is low enough that it poses a threat to human health and life if adequate protection is not taken against hypothermia and frostbite. The exact definition varies from state to state, and areas prone to colder temperatures will often require the wind chill to be lower before issuing an advisory.
Example
The following is an example of a Wind Chill Advisory issued by the National Weather Service office in Detroit, Michigan.
920 WWUS43 KDTX 212131 WSWDTX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 431 PM EST FRI JAN 21 2011 ...EXTREME COLD WIND CHILLS TONIGHT... .COLD TEMPERATURES IN ADDITION TO WINDS INCREASING TONIGHT AHEAD OF A LOW PRESSURE SYSTEM WILL ALLOW WIND CHILLS TO DROP BETWEEN -15 AND -20 ACROSS THE NORTHERN THUMB AND SAGINAW VALLEY TONIGHT. MIZ047>049-053>055-062-063-220545- /O.NEW.KDTX.WC.Y.0001.110122T0500Z-110122T1500Z/ MIDLAND-BAY-HURON-SAGINAW-TUSCOLA-SANILAC-LAPEER-ST. CLAIR- INCLUDING THE CITIES OF...MIDLAND...BAY CITY...BAD AXE... SAGINAW...CARO...SANDUSKY...LAPEER...PORT HURON 431 PM EST FRI JAN 21 2011 ...WIND CHILL ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 10 AM EST SATURDAY... THE NATIONAL WEATHER SERVICE IN DETROIT/PONTIAC HAS ISSUED A WIND CHILL ADVISORY...WHICH IS IN EFFECT FROM MIDNIGHT TONIGHT TO 10 AM EST SATURDAY. IMPACTS... * COLD WIND CHILLS MAY LEAD TO FROST BITE AND HYPOTHERMIA IF PRECAUTIONS ARE NOT TAKEN. HAZARDOUS WEATHER... * WIND CHILLS ARE EXPECTED TO FALL BETWEEN -15 AND -20 DEGREES LATE TONIGHT THROUGH TOMORROW MORNING. PRECAUTIONARY/PREPAREDNESS ACTIONS... * A WIND CHILL ADVISORY MEANS THAT VERY COLD AIR AND STRONG WINDS WILL COMBINE TO GENERATE LOW WIND CHILLS. THIS WILL RESULT IN FROST BITE AND LEAD TO HYPOTHERMIA IF PRECAUTIONS ARE NOT TAKEN. IF YOU MUST VENTURE OUTDOORS...MAKE SURE YOU WEAR A HAT AND GLOVES. && $$ RKReferences
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