Flare Forecasting

Using the daily observation of the photosphere performed by the Equatorial Spar of INAF - Catania Astrophysical Observatory, we provide an indication of the probabilities that each sunspot group visible on the solar disc may host solar flares of C-, M- and X- class.
The probabilities shown below are calculated using the USSPS acquired on 28 May 2026 at 07:00 UT. They are valid for the subsequent 24 hours.
The sunspot groups capability of hosting flares is based on the Poisson statistics of five parameters: number of sunspots and pores, projected area of sunspot group in tens of millionths of the solar hemisphere, group type according to Zurich classification, type of penumbra of the main sunspot, and relative importance between leading sunspot and density of the sunspot population.

Forecasting method description
NOAA AR
Catania Sunspot Group
Flare C-class
Flare M-class
Flare X-class


4443


14
9%
1%
0%


4444


17
13%
1%
0%


4445


24
11%
1%
0%


4452


26
33%
7%
1%


4447


27
32%
6%
0%


28
9%
1%
0%


NNNN


29
28%
4%
1%


4449


30
15%
1%
0%


4448


31
16%
2%
0%


4446


32
10%
1%
0%


4453


34
9%
1%
0%


4454


36
9%
1%
0%


4455


37
23%
3%
0%
Osservatorio Astrofisico di Catania
Via S.Sofia 78, 95123 Catania ITALY
Phone: (+39) 0957332111; FAX: (+39) 095330592
E-Mail (PEC): inafoacatania@pcert.postecert.it