Sunspot AR1785 has grown just under 25,000 miles in 24 hours. It has widened and lengthened, which could lead to instability in the magnetic field of the sunspot. When the magnetic field loops and swirls it can collapse back in on itself; it's this that produces strong flares.
The shape of this region is changing all the time to a much greater extent than is seen in most sunspots. AR1785 is now 11 times the size of the Earth and is still growing as it moves across the Sun.
Within the next day or two it will be at the center of the Sun disc and any flares at that point will hit Earth directly.
There is an excellent video showing the change in size and shape here.
Today's sunspot number is 115 and NOAA estimates the chance of an M-Class flare today at 55% and an X-Class at 10%, though this is apt to be revised in light of the dynamic nature of the spot.
Chris Carrington is a writer, researcher and lecturer with a background in science, technology and environmental studies. Chris is an editor for The Daily Sheeple, where this article first appeared. Wake the flock up!