Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 30, 2014 at 06:00 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 October 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update October 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update October 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update October 10, 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 October 11, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet to unsettled on October 29. Solar wind speed at SOHO ranged between 328 and 448 km/s.

Solar flux at 20h UTC on 2.8 GHz was 150.4 (increasing 1.4 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 143.2. The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.6). Three hour interval K indices: 32121220 (planetary), 32222311 (Boulder).

The background x-ray flux is at the class C2 level.

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 196) and 12 active regions using 1K resolution (SN: 157) SDO images on the visible solar disk.

Region 12192 [S16W80] rotated to the southwest limb still producing C and M class flares as the region decayed slowly. A major flare is possible while the region rotates out of view.
Region 12194 [S12W47] decayed slowly and quietly.
Region 12195 [N07W21] was quiet and stable.
Region 12196 [S05E03] was quiet and stable.
Region 12197 [S13W00] decayed slowly and quietly.
Region 12198 [S14W31] decayed slowly and quietly.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3944 [S16E77] developed slowly and quietly.
New region S3947 [S18E38] emerged with several spots.
New region S3948 [S10E35] emerged with penumbra spots.
New region S3949 [S05E80] rotated into view.
New region S3950 [N12E29] emerged with penumbra spots.
New region S3951 [S22E04] was observed with penumbra spots.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
C3.3 03:14   12192  
C8.4/1F 03:58 S13W72 12192  
M1.0 (LDE) 08:20   12192  
M1.2 10:01   12192  
C5.5 14:00   12192  
M1.4 14:33 S16W81 12192  
M1.0 16:20   12192  
M1.3 18:50   12192  
C6.8 19:38   12192  
M2.3 21:22   12192  
C2.7 23:03   12192  
C3.6 23:25   12192  
C7.1 00:11 (Oct.30)   12192  

Coronal mass ejections (CMEs)

October 27-29: No obviously Earth directed CMEs were observed in LASCO and STEREO 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 northern hemisphere coronal hole (CH641) will likely rotate across the central meridian on October 29-30.

Propagation

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

Forecast

The geomagnetic field is expected to be quiet on October 30-31. Quiet to unsettled is possible on November 1-2 due to effects from CH641

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
12192 2014.10.16
2014.10.17
10 16 5 S12W84 1500 FKC EKC beta-gamma-delta

location: S16W80

12194 2014.10.19
2014.10.21
2 1 1 S11W49 0030 HAX HAX area: 0050

location: S12W47

12195 2014.10.21
2014.10.22
3 13 6 N07W21 0050 CSO CSO area: 0110
S3930 2014.10.22       N07W49           plage
12197 2014.10.23
2014.10.24
4 8 6 S13E01 0030 CSO BXO  
12196 2014.10.23
2014.10.24
1 6 4 S03W00 0010 AXX CRO location: S05E03
S3936 2014.10.25       S29W40           plage
S3937 2014.10.25       S16W10          
S3941 2014.10.27       S15E16           plage
12198 2014.10.27
2014.10.28
4 6 2 S13W33 0010 AXX CRO location: S14W31
S3944 2014.10.28   5 3 S17E65 0025   CRO  
S3946 2014.10.28       S03W55         plage
S3947 2014.10.29   9 4 S18E38 0020   CRO    
S3948 2014.10.29   2 2 S10E35 0006   AXX    
S3949 2014.10.29   1 1 S05E80 0070   HAX    
S3950 2014.10.29   7 2 N12E29 0013   BXO    
S3951 2014.10.29   2 1 S22E04 0005   AXX    
Total spot count: 24 76 37  
Sunspot number: 84 196 157  (total spot count + 10 * number of spotted regions)
Weighted SN: 49 113 74  (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): 50 69 86 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
2013.06 110.1 113.7 52.5 62.6 (+2.7) 12.60
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 (82.7 projected, +1.9) 7.88
2014.05 129.7 132.9 75.2 (82.3 projected, -0.4) 5.75
2014.06 122.0 125.8 71.0 (81.1 projected, -1.2) 6.72
2014.07 137.4 141.8 72.5 (79.4 projected, -1.7) 4.50
2014.08 124.7 127.9 74.7 (77.1 projected, -2.3) 7.71
2014.09 146.6 148.1 87.6 (73.8 projected, -3.3) 9.78
2014.10 155.6 (1)   85.9 (2A) / 91.8 (2B) / 82.8 (2C) (71.4 projected, -2.4) (8.9)

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.