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21 December 2001
20011220 Week Rotation Today Rotation Week 20011222

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
09733 N12W91
βγδ/βγδ Cao/Eai 0070/0310 03/15 -
09737 S29W91
αγδ/- Hsx/--- 0010/---- 01/-- -
09738 S18W48
βγδ/βγδ Cro/Dao 0020/0040 03/08 -
09741 N05W35
βγδ/βγδ Bxo/Cao 0010/0020 05/04 -
09742 N10W01
βγδ/βγδ Eki/Eai 0530/0320 45/24 -
09743 S11E05
βγδ/αγδ Cao/Hax 0120/0120 05/02 -
09745 N17E19
βγδ/βγδ Bxo/Bxo 0030/0030 08/04 -
09746 S17W34
βγδ/βγδ Bxo/Bxo 0010/0020 03/02 -
09747 N12E44
βγδ/βγδ Cao/Bxo 0090/0030 05/02 -
09748 S11E22
βγδ/βγδ Cso/Cso 0030/0030 04/04 -
09749 S08E58
βγδ/βγδ Cso/Cso 0080/0080 03/03 -
09750 S16W78
βγδ/- Dso/--- 0030/---- 03/-- -
09751 N04E54
αγδ/- Hax/--- 0220/---- 01/-- -

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

Events not associated with currently named NOAA regions: None

Note: The tabulated data are based on the most recent NOAA/USAF Active Region Summary issued on 21-Dec-2001 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 21-Dec-2001 23:30 .