http://spaceweather.com INCOMING STORM CLOUDS: Three or four CMEs that left the sun earlier this week will arrive in quick succession this weekend. Mostly, the blows they deliver to Earth's magnetic field are expected to be weak, but the combined impacts could stir up significant geomagnetic activity. NOAA forecasters put the odds of a high-latitude geomagnetic storm at 55% on Saturday, increasing to 75% on Sunday. Check http://spaceweather.com for updates. AURORA ALERTS: Would you like a call when geomagnetic storms are underway? Aurora alerts are available from http://spaceweathertext.com (text) and http://spaceweatherphone.com (voice). You are subscribed to the Space Weather mailing list, a free service of Spaceweather.com. New subscribers may sign up for space weather emails at http://spaceweather.com/services/ .