Welcome to the Flare Prediction System.
This page lists the active regions present on the Sun today, together with their probability
of producing C, M, or Xclass events. Flare probabilities are calculated using
NOAA Space Weather Prediction Center data
combined over 19691976 and 19881996 (details of which can be found in Bloomfield et al.,
2012, The Astrophysical Journal Letters, 747, L41, along with full forecast
verification testing). The percentage probabilities
are based on the number of flares produced by regions classified using the McIntosh classification
scheme (McIntosh, P., 1990, Solar Physics, 125, 251) during cycles 21 and 22. For example,
over both time periods there were 377 regions classified Eai. As this class produced 131 Mclass
events, the mean Mclass flare rate is ~131/377 or ~0.347 flares per day. Assuming the number of
flares per unit time is governed by Poisson statistics, we can estimate a flaring probability
for the following 24hours using P( one or more flares ) = 1  exp( mean ), i.e.,
P = 1  exp( 0.347 ) ~ 0.29, or 29% for an Eai class region to produce one or more Mclass
flares in the next 24hours. See Gallagher, P. T., Moon, Y.J., Wang, H., Solar Physics,
209, 171, (2002), Wheatland, M. S., 2001, Solar Physics, 203,
87 and Moon et al., 2001, Journal of Geophysical ResearchSpace Physics,
106(A12) 29951 for further details.
Click here for a description of the various active region classifications from the Royal Observatory of Belgium.
