Earth is entering a stream of solar wind flowing from a southern hole in the sun's atmosphere. First contact with the stream on Nov. 26 is producing green auroras around the Arctic Circle--but so far no geomagnetic storms. Wind speeds were elevated at an average speed of about 475 km/s. Forecast ... Solar wind conditions are expected to become further enhanced later today. A co-rotating interaction region (CIR) is expected to hit Earth's magnetic field late on Nov. 26th, according to NOAA forecasters. CIRs are transition zones between fast- and slow-moving solar wind streams. Solar wind plasma piles up in these regions, producing shock-like density gradients that can do a good job of sparking Arctic auroras. High-speed-solar-wind streams emanate from solar coronal holes. The fast wind interacts with upstream slow streams producing regions of enhanced magnetic field strength and particle density that are known as co-rotating interaction regions. Due to the reccuring nature of coronal holes near solar minimum, this results in periodic driving of the magnetosphere that can last for several days and input as much energy as a storm driven by a coronal mass ejection. High latitude skywatchers should be alert for aurora displays.