Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 22, 2014 at 05:05 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 on June 21. Solar wind speed at SOHO ranged between 382 and 459 km/s.

Solar flux at 20h UTC on 2.8 GHz was 101.2 (decreasing 11.8 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 138.2. The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 5.1). Three hour interval K indices: 22221101 (planetary), 22332211 (Boulder).

The background x-ray flux is at the class B1 level.

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 168) and 10 active regions using 1K resolution (SN: 141) SDO images on the visible solar disk.

Region 12087 [S18W75] was quiet and stable.
Region 12090 [N25W63] was quiet and stable.
Region 12092 [S18W60] was quiet and stable.
Region 12093 [S08W07] decayed slowly. There's weak polarity intermixing and further low level C class flares are possible.
Region 12094 [S17E04] decayed as the main penumbra fragmented.

Spotted regions not numbered (or interpreted differently) by SWPC:
New region S3559 [S10E01] was split off from AR 12093 as new positive polarity flux emerged.
New region S3560 [N08W69] emerged with penumbra spots.
New region S3561 [S20W24] emerged with a penumbra spot.
New region S3562 [N08E82] rotated into view.
New region S3564 [S19W14] emerged with a penumbra spot.

A filament eruption in the northeast quadrant began just after 03h and peaked near 05:30 UTC. A small CME was observed in STEREO-A imagery.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
C2.1/1F 11:17 S09E01 12093

Coronal mass ejections (CMEs)

June 19: A filament eruption began just after 15h UTC to the north of ARs 12093/S3538. A partial halo CME was observed, the CME could have Earth directed extensions.
June 20-21
: 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 (CH623) could rotate into an Earth facing position on June 23-24.

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 22-25. On June 22-23 there is a chance of a weak disturbance associated with the CME observed on June 19. Quiet to unsettled conditions are possible on June 26-27 due to effects from CH623.

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
12087 2014.06.09
2014.06.10
2 2 2 S19W76 0080 CAO DSO area: 0120
12090 2014.06.10
2014.06.11
1 2 2 N25W65 0060 HSX CSO area: 0130
12092 2014.06.11
2014.06.12
3 5 3 S18W63 0030 CAO CRO

 

12093 2014.06.15
2014.06.16
17 23 13 S09W06 0060 DAO DRI beta-gamma
12094 2014.06.15
2014.06.16
4 11 5 S18E02 0050 HAX CAO  
S3541 2014.06.15       S15W44           plage
S3547 2014.06.16       N16W32           plage
S3549 2014.06.17       S20W38         plage
S3553 2014.06.18       N15W50           plage
S3554 2014.06.18       S12W59           plage
S3555 2014.06.18       N03W23           plage
S3556 2014.06.19       N11W16           plage
S3557 2014.06.20       N15W34         plage
S3558 2014.06.20       N15E03         plage
S3559 2014.06.21   19 11 S10E01 0050   DRI    
S3560 2014.06.21   2 1 N08W69 0006   BXO    
S3561 2014.06.21   1 1 S20W24 0004   AXX    
S3562 2014.06.21   2 2 N08E82 0100   CSO    
S3564 2014.06.21   1 1 S19W14 0003   AXX    
Total spot count: 27 68 41  
Sunspot number: 77 168 141  (total spot count + 10 * number of spotted regions)
Weighted SN: 52 97 70  (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): 46 59 78 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
2014.06 128.4 (1)   83.7 (2A) / 119.6 (2B) / 79.4 (2C) (70.5 projected, -2.7) (7.5)

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.