Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 28, 2014 at 05:45 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update October 1, 2014)] [Cycle 24 progress (last update November 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update November 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update November 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update November 1, 2014)]

[Noon SDO sunspot count 1K Reference: 4K (large file) (updated daily)]

[POES auroral activity level October 2009 - December 2012]
[Solar polar fields vs solar cycles - updated November 22, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet to unsettled on November 27. Solar wind speed at SOHO ranged between 288 and 440 km/s.

Solar flux at 18h UTC on 2.8 GHz was 178.8 (increasing 57.6 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 149.6 - the highest since May 7, 2014). The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.1). Three hour interval K indices: 13211212 (planetary), 03112322 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time), spots were observed in 15 active regions using 2K resolution (SN: 344) and 13 active regions using 1K resolution (SN: 243) SDO images on the visible solar disk.

Region 12216 [S13W25] decayed slowly and was mostly quiet.
Region 12217 [S19E15] decayed slowly and quietly.
Region 12218 [N16E29] was quiet and stable.
Region 12219 [N03W20] was mostly quiet. There is weak polarity intermixing and a minor M class flare is possible.
Region 12220 [S17W12] was quiet and stable.
Region 12221 [N04E57] developed slowly and quietly.
Region 12222 [S19E57] produced many C flares and has M class flare potential.
New region 12223 [N17W11] emerged on November 26 and was numbered the next day by SWPC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4028 [S07E00] reemerged with a penumbra spot.
S4029 [N11W41] was quiet and stable.
S4035 [S23E45] developed slowly and quietly.
S4037 [N12E11] was quiet and stable.
New region S4039 [S19E32] emerged with penumbra spots.
New region S4041 [N26E18] emerged with a penumbra spot.
New region S4042 [S05E37] was observed with a penumbra spot.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
C8.1 00:47 S21E73 12222  
C3.7 02:01   12222  
C5.0 04:48 S21E73 12222  
C2.8 05:53 S10W15 12216  
C5.4 07:02 S21E73 12222  
C3.3 08:48   12222  
C4.8 09:41 S22E68 12222  
C4.6 10:20   12222  
C5.1 10:59   12222  

Coronal mass ejections (CMEs)

November 25-27: No obviously Earth directed CMEs were observed in LASCO imagery.

Coronal holes

[Coronal hole history (since October 2002)]
[Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago]

A recurrent northern hemisphere coronal hole (CH644) was in an Earth facing position on November 25-26. The development of AR 12219 reduced the southernmost extension of this CH.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is poor to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be mostly quiet on November 28-30 with a chance of unsettled intervals on November 28 due to weak effects from CH644.

Coronal holes (1) Coronal mass ejection (2) M and X class flares (3)
     

1) Effects from a coronal hole could reach Earth within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Green: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% probability.

Active solar regions

(Click on image for 2K resolution) Compare to the previous day's image. 0.5K image

When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.

Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.

Active region Date numbered
detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlay
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12214 2014.11.15
2014.11.16
      S12W89            
12215 2014.11.15
2014.11.17
      N09W87           plage
12216 2014.11.19
2014.11.20
20 31 16 S13W25 0200 CAI CKI

beta-gamma

area: 0300

S4008 2014.11.19       N21W30           plage
S4012 2014.11.21       S03W46           plage
12217 2014.11.22
2014.11.23
15 37 16 S20E17 0130 EAI DSI area: 0140
S4016 2014.11.22       N12W18           plage
S4017 2014.11.22       N05W49           plage
S4020 2014.11.23       N14E22           plage
12218 2014.11.23 1 9 3 N16E28 0140 HSX CSO

area: 0220

S4023 2014.11.23       N02W30           plage
12219 2014.11.24 16 34 24 N04W21 0200 DAI DKC beta-gamma

area: 0370

12220 2014.11.24 2 8 6 S16W13 0010 AXX CRO  
S4028 2014.11.24       S05E05           plage
S4029 2014.11.24   2 1 N11W41 0005   AXX  
S4030 2014.11.24       N00W37           plage
12221 2014.11.25
2014.11.26
10 27 17 N04E56 0160 DAI DAC area: 0230
S4033 2014.11.25       S08W13           plage
12222 2014.11.26 10 28 17 S20E59 0120 DAI DKC beta-gamma

area: 0450

S4035 2014.11.26   8 4 S23E45 0030   DRO  
12223 2014.11.26
2014.11.27
1 6 6 N17W11 0010 BXO DRO  
S4037 2014.11.26   1 1 N12E11 0005   HRX  
S4038 2014.11.26       S28W11         plage
S4039 2014.11.27   2 1 S19E32 0005   BXO    
S4041 2014.11.27   1   N26E18 0002   AXX    
S4042 2014.11.27   1   S05E37 0001   AXX    
Total spot count: 75 194 113  
Sunspot number: 155 344 243  (total spot count + 10 * number of spotted regions)
Weighted SN: 105 251 170  (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)
Relative sunspot number (Wolf number): 93 120 134 k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for MSN 2K, k = 0.55 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number Average ap
(3)
Measured 1 AU
2013.07 115.5 119.3 57.0 65.5 (+2.9) 9.47
2013.08 114.6 118.3 66.0 69.0 (+3.5) 8.27
2013.09 102.6 103.7 36.9 73.1 (+4.1) 5.23
2013.10  132.1 131.2 85.6 75.0 (+1.9) 7.71
2013.11  148.3 145.1 77.6 75.4 (+0.4) 5.68
2013.12 147.7 143.1 90.3 76.0 (+0.6) 4.68
2014.01 157.4 152.4 81.8 77.3 (+1.3) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) 78.4 (+1.1) 10.70
2014.03 149.9 148.5 91.9 80.8 (+2.4) 4.88
2014.04 143.9 144.8 84.7 81.9 (+1.1)
(likely solar max)
7.88
2014.05 129.7 132.9 75.2 (80.3 projected, -1.6) 5.75
2014.06 122.0 125.8 71.0 (78.7 projected, -1.6) 6.72
2014.07 137.4 141.8 72.5 (77.1 projected, -1.6) 4.50
2014.08 124.7 127.9 74.7 (74.7 projected, -3.0) 7.71
2014.09 146.6 148.1 87.6 (71.5 projected, -3.2) 9.78
2014.10 153.4 152.9 60.6 (69.0 projected, -2.5) 8.96
2014.11 152.1 (1)   86.0 (2A) / 95.6 (2B) / 85.3 (2C) (67.3 projected, -1.7) (9.4)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official WDC-SILSO international sunspot number is typically 30-50% lower. 2B) Boulder SN current month average to date. 2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international GFZ Potsdam WDC ap indices.

This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to the UTC day. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.