Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 29, 2014 at 05:30 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 unsettled on June 28. Solar wind speed at SOHO ranged between 283 and 337 km/s.

Solar flux at 20h UTC on 2.8 GHz was 114.6 (increasing 11.3 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 134.6. The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 5.4). Three hour interval K indices: 11113211 (planetary), 22222412 (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 13 active regions using 2K resolution (SN: 175) and 10 active regions using 1K resolution (SN: 123) SDO images on the visible solar disk.

Region 12096 [N10W10] was mostly quiet and stable.
Region 12097 [N13W02] was quiet and stable.
Region 12098 [S08W34] decayed slowly and quietly.
Region 12100 [N11E39] was mostly quiet and stable.
New region 12102 [N12E67] rotated into view on June 27 and was numbered by SWPC the next day.
New region 12103 [S09E51] rotated into view on June 26 with SWPC numbering the region 2 days later as it began to decay.
New region 12104 [S10E79] rotated into view as a compact region. C and minor M class flares are possible.

Spotted regions not numbered (or interpreted differently) by SWPC:
New region S3587 [S23E13] emerged early in the day with 2 spots, then began to decay.
New region S3589 [S21E84] rotated partially into view.
New region S3590 [S22E72] rotated into view with penumbra spots.
New region S3591 [S12E57] emerged with penumbra spots.
New region S3592 [S11E21] emerged with penumbra spots.
New region S3593 [S06E39] emerged with penumbra spots.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
C3.4 07:01 NE limb  
C3.4 07:44   12104
C4.2 (LDE) 21:05    
C3.6 23:33 NE limb  

Coronal mass ejections (CMEs)

June 26-28: 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 trans equatorial coronal hole (CH624) was in an Earth facing position on June 27.

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 poor.

Forecast

The geomagnetic field is expected to be mostly quiet on June 29-July 1. On June 30 there is a possibility of unsettled intervals due to weak effects from CH624.

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
12096 2014.06.21
2014.06.22
5 5 4 N09W10 0070 CSO CAO

area: 0120

12097 2014.06.22 1 4 3 N13W03 0030 HAX CAO area: 0060
12098 2014.06.23
2014.06.24
1 2 1 S09W35 0010 HRX AXX  
12100 2014.06.25
2014.06.27
5 12 5 N11E39 0010 BXO CRO  
S3576 2014.06.25       S27W44     AXX     plage
S3578 2014.06.26       N12W10         merged with AR 12096
S3579 2014.06.26       S10E22           plage
12099 2014.06.26
2014.06.27
      S16W19         plage
12101 2014.06.26
2014.06.27
      S07W30         plage
12103 2014.06.26
2014.06.28
2 1   S10E52 0010 AXX AXX  
S3583 2014.06.27       N00E58         plage
S3585 2014.06.27       S48W25         plage
12102 2014.06.27
2014.06.28
1 1 1 N11E65 0020 HAX HRX location: N12E67
12104 2014.06.28 4 9 4 S10E78 0080 DAO DKC   beta-gamma

area: 0400

S3587 2014.06.28   1 1 S23E13 0004   AXX    
S3589 2014.06.28   1   S21E84 0060   HSX    
S3590 2014.06.28   2 1 S22E72 0006   BXO    
S3591 2014.06.28   2   S12E57 0002   AXX    
S3592 2014.06.28   2 1 S11E21 0006   BXO    
S3593 2014.06.28   3 2 S06E39 0010   BXO    
Total spot count: 19 45 23  
Sunspot number: 89 175 123  (total spot count + 10 * number of spotted regions)
Weighted SN: 42 76 54  (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): 53 61 68 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
2014.06 121.2 (1)   100.0 (2A) / 107.1 (2B) / 77.1 (2C) (70.5 projected, -2.7) (6.8)

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.