High-latitude sky watchers should be alert for auroras. A strong (Kp=7) geomagnetic storm is in progress.

Earth's magnetic field has been strongly disturbed since approximately 1300 UT on Sept. 26th when a CME hit our planet. The impact strongly compressed the magnetosphere, exposing geosynchronous satellites to solar wind plasma, and ignited auroras around both poles. Gordon McLellan photographed these pastels over Lake Michigan after sunset on Sept. 26th:

Aurora
© Gordon McLellanImage Taken: Sep. 26, 2011
Location: Lake Michigan, Manistee, Michigan, USA
Aurora_1
© Gordon McLellan

More Photos:
From Minoru Yoneto of Queenstown, New Zealand; from Ole Ambrosiussen of Hvinningdal, Silkeborg, Denmark; from Steven Graham of Christchurch, New Zealand; from Mika Puurula of Sotkamo, Finland; from Jonathan Tucker of Whitehorse, Yukon; from Julius Jahre Sætre of Vestfold, Norway; from Vanessa Gervais of Chisasibi, Quebec, Canada; from Sternwarte Riesa of Segelflugplatz Riesa/ Canitz, Germany; from Elizabeth Gyurgyak of Tananger, Norway; from Reed Ingram Weir of Northumberland, UK; from Krzysztof Polakowski of Rimforsa, Sweden; from Thilo Bubek of Tromsø, Norway