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22 May 2000
20000521 Week Rotation Today Rotation Week 20000523

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 X-class events. Flare probabilities are calculated using NOAA Space Weather Prediction Center data combined over 1969-1976 and 1988-1996 (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 M-class events, the mean M-class 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 24-hours 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 M-class flares in the next 24-hours.

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 Research-Space Physics, 106(A12) 29951 for further details.

Click here for a description of the various active region classifications from the Royal Observatory of Belgium.

Region Flare Probabilities (%)
Number McIntosh C-class M-class X-class
No Prediction Found

NOTE: Occurrence of '...' indicates that McIntosh class was not observed in the period over which the Poisson flare rate statistics were determined. Values in parantheses/brackets give the NOAA/SWPC forecast probabilities for the occurrence of one or more C-, M-, or X-class flares. When viewed in real-time and before 22:00 UT, NOAA predictions are valid up to 22:00 UT on the current date. When viewed in real-time after 22:00 UT (or when viewing past dates), NOAA predictions are valid up to 22:00 UT on the following date. The most recent data can also be found at NOAA's 3-day Space Weather Predictions page.

Please contact Peter Gallagher if you have any comments or questions regarding this research.

Today's/Yesterday's NOAA Active Regions
NOAA Number
McIntosh Class
Sunspot Area
Number of Spots
08996 S21W62
β/β Ekc/Ekc 0810/0870 39/44 C1.7(21:34)
/ C2.1(19:21)
08998 S12W47
βγδ/βγ Eac/Eac 0450/0420 37/32 - / C2.5(06:30)
08999 N20W49
β/β Cro/Bxo 0030/0020 09/09 -
09002 N19W23
β/βγ Fki/Fki 0730/0720 58/49 -
09004 N12W35
βδ/βδ Dkc/Dkc 0530/0520 13/14 - / C1.9(16:38)
09009 S15E15
β/α Cso/Hsx 0040/0030 05/02 -
09010 N21E17
β/β Cao/Cao 0110/0090 17/11 -
09011 N17E26
α/α Hkx/Hax 0250/0240 02/02 - / C3.7(00:07)
09012 S29W63
α/β Axx/Bxo 0000/0010 01/04 -

Class (HH:MM) -Today
Class (HH:MM) -Yesterday

Events not associated with currently named NOAA regions: C6.3(01:20) C5.1(03:52) C1.3(11:56) C1.8(14:01) C1.2(16:23) C2.4(08:08)

Note: The tabulated data are based on the most recent NOAA/USAF Active Region Summary issued on 22-May-2000 00:30 . The greyed out and light-blue entries are values from the previous day. Slashed cells indicate that the active region has no spots. The latest positions of the active regions are given in both heliographic and heliocentric co-ordinates. The region positions are valid on 22-May-2000 23:30 .