Tornado watch includes Iowa and Illinois counties

UPDATED:  The National Weather Service expanded a Quad Cities-area tornado watch to include counties in Iowa and Illinois.

The watch that included Illinois counties was issued just before 4:30 p.m. and is in effect until midnight.  Iowa counties were added to the watch area just after 7 p.m. and they remain under a tornado watch until 1 a.m. Friday.

Iowa counties in the watch area are Des Moines, Henry, Lee, Louisa and Washington counties.

Illinois counties in the watch area are Bureau, Fulton, Hancock, Henderson, Henry, Knox, La Salle, Mc Donough, Mercer, Putnam, Stark and Warren counties.

A tornado watch is issued when weather conditions exist that would allow tornadoes to develop.

See the full list of area counties included in the tornado watch at this link:  http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=dvn&wwa=tornado%20watch

In addition to the tornado watch, Lee and Ogle counties in Illinois were among those under a severe thunderstorm watch until midnight.  See the full list of counties included in the severe thunderstorm watch at this link:  http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=dvn&wwa=severe%20thunderstorm%20watch