Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 9, 2014 at 04:10 UTC.

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

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

Recent activity

The geomagnetic field was quiet to major storm on June 8. Solar wind speed at SOHO ranged between 396 and 717 km/s under the influence of CME effects.

Solar flux at 20h UTC on 2.8 GHz was 148.6 (decreasing 14.3 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 148.6. The Potsdam WDC planetary A index was 37 (STAR Ap - based on the mean of three hour interval ap indices: 36.9). Three hour interval K indices: 36655432 (planetary), 45544433 (Boulder).

The background x-ray flux is at the class B6 level.

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 311) and 10 active regions using 1K resolution (SN: 200) SDO images on the visible solar disk.

Region 12077 [S03W52] decayed slowly and quietly.
Region 12079 [N12W27] developed slowly and quietly.
Region 12080 [S11E04] decayed slighlty, however, there is still a magnetic delta in the trailing spot section. An M class flare is possible.
Region 12081 [N05W15] regained trailing penumbra spots.
Region 12082 [N15W02] decayed slowly and quietly.
Region 12084 [S12W42] was quiet and stable.
Region 12085 [S20W04] developed quickly and extended longitudinally. There is a weak magnetic delta structure centrally. A major flare is possible.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3510 [S11E08] was quiet and stable.
S3512 [N16E56] was quiet and stable.
S3515 [S17E22] was quiet and stable.
New region S3518 [N03E35] emerged with a few spots.
New region S3519 [S32W27] emerged with a penumbra spot.

C2+ Flares (GOES):

Magnitude Time (UTC) Location AR
C5.2 23:54 SE limb  

Coronal mass ejections (CMEs)

June 6-8: 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 small trans equatorial coronal hole (CH622) rotated into an Earth facing position on June 8-9.

Coronal hole map

Propagation

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

Forecast

The geomagnetic field is expected to be quiet on June 9-11. Late on June 11 and on June 12 there is a chance of unsettled intervals due to effects from CH622.

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
12077 2014.05.30 3 3 2 S04W52 0080 CSO CSO

area: 0100

12078 2014.05.30
2014.06.01
      S20W85           plage

real location: S19W79

12079 2014.05.31
2014.06.01
6 11 7 N12W27 0120 DSO DSO area: 0180
S3492 2014.05.31       N11W49           plage
12081 2014.06.01
2014.06.04
  8 2 N05W26 0010   BXO location: N05W15
S3496 2014.06.02       N17W26           plage
12080 2014.06.02
2014.06.03
26 53 27 S12W09 0340 DKC DAC beta-gamma-delta

area: 0430

S3499 2014.06.03       S09W16         plage
S3501 2014.06.04       S23W10           plage
S3502 2014.06.04       S12W27           plage
12082 2014.06.04
2014.06.05
14 25 15 N16W02 0280 DKI DHI area: 0340
S3505 2014.06.05       S15E20           plage
12085 2014.06.05
2014.06.06
32 61 34 S20W03 0300 EKC EAC beta-gamma-delta

area: 0700

12084 2014.06.06 3 8 3 S12W42 0010 BXO DRO  
S3507 2014.06.06       N12W37           plage
S3510 2014.06.06   10 5 S11E08 0020   AXX  
S3512 2014.06.07   1   N16E56 0002   AXX    
S3515 2014.06.07   6 3 S17E22 0015   BXO  
S3516 2014.06.07       N22E50         plage
S3518 2014.06.08   4 2 N03E35 0015   DRO    
S3519 2014.06.08   1   S32W27 0002   AXX    
Total spot count: 84 191 100  
Sunspot number: 144 311 200  (total spot count + 10 * number of spotted regions)
Weighted SN: 124 227 136  (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): 86 109 110 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
2013.02 104.3 101.8 38.0 58.4 (-0.3) 6.11
2013.03 111.3 110.2 57.9 57.5 (-0.9) 10.56
2013.04 124.8 125.9 72.4 57.9 (+0.4) 5.40
2013.05 131.4 134.3 78.7 59.9 (+2.0) 9.73
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 (75.8 projected, +0.4) 4.68
2014.01 157.4 152.4 82.0 (76.4 projected, +0.6) 5.44
2014.02 170.3
(cycle peak)
166.3 102.8 (cycle peak) (76.2 projected, -0.2) 10.70
2014.03 149.9 148.5 92.2 (76.6 projected, +0.4) 4.88
2014.04 143.9 144.8 84.7 (75.8 projected, -0.8) 7.88
2014.05 129.7 132.9 75.2 (73.2 projected, -2.6) 5.75
2014.06 123.4 (1)    31.3 (2A) / 104.4 (2B) / 87.8 (2C) (70.5 projected, -2.7) (9.1)

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.