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30 September 2014
20140929 Week Rotation Today Rotation Week 20141001

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
12171 Cso 17(20) 3(1) 0(1)
12172 Fhc 0(90) 55(50) 0(10)
12173 Eac 81(90) 30(50) 14(10)
12175 Ekc 93(90) 82(50) 20(10)
12176 Bxo 6(5) 1(1) 0(1)
12177 Eac 81(65) 30(20) 14(5)
12178 Cso 17(20) 3(1) 0(1)
12179 Hsx 5(10) 3(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
12171 S10W71
(892",-201")
β/β Cso/Cao 0030/0100 05/12 -
12172 S12W48
(698",-272")
βγ/βγ Fhc/Fkc 0510/0490 28/56 -
12173 S16W59
(790",-318")
βγ/βγ Eac/Dac 0150/0160 11/22 -
12175 N17W69
(856",239")
βγδ/βγδ Ekc/Dkc 0500/0390 11/23 -
12176 N08W18
(294",26")
β/ Bxo/ 0010/ 04/ -
12177 N11E26
(-413",82")
βγ/βγ Eac/Eai 0200/0120 17/12 -
12178 S03E40
(-616",-136")
β/β Cso/Cao 0120/0050 03/04 -
12179 S10E51
(-734",-235")
α/α Hsx/Hsx 0040/0060 01/01 -

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 30-Sep-2014 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 30-Sep-2014 09:04 UT .