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19 October 2012
20121018 Week Rotation Today Rotation Week 20121020

NOAA
8 Active Regions

Flare Forecast
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
11586 Hsx 4(1) 1(1) 0(1)
11589 Bxi 0(25) 0(1) 0(1)
11590 Bxo 5(1) 1(1) 0(1)
11591 Hsx 4(1) 1(1) 0(1)
11593 Hax 7(10) 2(1) 0(1)
11594 Cro 9(25) 1(1) 0(1)
11596 Eao 31(60) 9(10) 0(1)
11597 Dro 17(25) 5(1) 0(1)

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.


IDL Access

Today's NOAA Active Regions
Group Number
Location
Hale
Class
McIntosh Class
Sunspot
Area
Number of Spots
Flares
History
11586 S13W91
(923",-209")
αγδ/αγδ Hsx/Hsx 0050/0060 01/01 -
11589 N12W59
(796",138")
βγδ/βγδ Bxi/Dsi 0020/0090 13/14 C1.3(01:06)
C3.6(20:46)
11590 S30W43
(561",-544")
βγδ/βγδ Bxo/Cro 0010/0010 02/03 -
11591 N08W22
(353",25")
αγδ/βγδ Hsx/Dso 0170/0130 01/06 -
11593 N18E22
(-339",190")
αγδ/αγδ Hax/Hax 0030/0040 03/01 -
11594 S27E09
(-132",-530")
βγδ/βγδ Cro/Dao 0040/0050 04/04 C1.7(18:42)
11596 N11E59
(-799",121")
βγδ/βγδ Eao/Eao 0300/0300 04/04 C1.8(05:10)
11597 S21W44
(616",-415")
βγδ/βγδ Dro/Dro 0020/0020 04/04 -

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 19-Oct-2012 00:30 UT , the values to the right of the forward slashes representing yesterdays values or events. Regions with no data in above property fields have decayed and exhibit no spots. The region positions are valid on 19-Oct-2012 21:00 UT .