Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 11, 2014 at 04:50 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 10. Solar wind speed at SOHO ranged between 352 and 471 km/s, after 10h UTC likely under the influence of a low to moderate speed coronal hole stream.

Solar flux at 20h UTC on 2.8 GHz was 166.2 (increasing 3.0 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 139.6. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.6). Three hour interval K indices: 11122222 (planetary), 01233312 (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: 318) and 14 active regions using 1K resolution (SN: 235) SDO images on the visible solar disk.

Region 12077 [S03W82] decayed slowly and quietly.
Region 12079 [N12W54] developed slowly and has polarity intermixing. A minor M class flare is possible.
Region 12080 [S11W37] decayed slowly losing spots and area. There is still a weak magnetic delta structure in the trailing spot section, a minor M class flare is possible.
Region 12082 [N15W28] developed slowly and quietly.
Region 12084 [S12W69] decayed slowly and quietly.
Region 12085 [S20W30] decayed slowly and was mostly quiet.
Region 12086 [N04E08] decayed slowly and quietly.
New region 12087 [S18E70] rotated into view on June 9 and was numbered the next day by SWPC. The region produced 2 X class flares. While the region still has a magnetic delta structure centrally, the delta became smaller after the flares. Further major flares are possible.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3510 [S12W19] was quiet and stable.
S3512 [N17E30] reemerged with several spots.
S3522 [S20E09] reemerged with penumbra spots.
S3524 [S16E30] was quiet and stable.
S3525 [N07W21] was quiet and stable.
New region S3526 [N24E79] rotated into view.
New region S3528 [N24W32] emerged with a penumbra spot.

C2+ Flares (GOES):

Magnitude Time (UTC) Location AR
C2.4 06:19 S15W26 12080
C3.9 08:25   12087
C5.1 09:31   12087
C5.0 10:17   12087
X2.2 11:42 S15E80 12087
X1.5/1F 12:52 S17E82 12087
C2.1 00:07 (June 11)   S3512

Coronal mass ejections (CMEs)

June 8-9: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
June 10: An asymmetric full halo CME was observed after the X flares in AR 12087. The CME could reach Earth on June 13.

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 poor to fair.

Forecast

The geomagnetic field is expected to be quiet on June 11. Onn June 11 and on June 12 there is a chance of unsettled intervals due to effects from CH622. On June 13-14 unsettled and active intervals are possible due to CME effects.

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 1 1 1 S04W80 0020 HRX AXX

area: 0006

12079 2014.05.31
2014.06.01
6 17 9 N13W56 0110 DSO DSC area: 0230
12081 2014.06.01
2014.06.04
      N05W56         location: N04W46
S3496 2014.06.02       N17W52           plage
12080 2014.06.02
2014.06.03
26 29 16 S12W36 0320 DKC EKC beta-gamma-delta

area: 0490

S3499 2014.06.03       S09W42           plage
S3501 2014.06.04       S23W36           plage
S3502 2014.06.04       S12W53           plage
12082 2014.06.04
2014.06.05
14 27 18 N15W28 0220 DAI DKI area: 0300
S3505 2014.06.05       S15W06           plage
12085 2014.06.05
2014.06.06
24 53 28 S20W30 0460 EKC EKC beta-gamma

area: 0680

12084 2014.06.06 3 2 1 S12W70 0010 BXO CRO  
S3510 2014.06.06   7 4 S12W19 0020   BXO  
S3512 2014.06.07   8 4 N17E30 0025   CRO    
S3515 2014.06.07       S18W06         plage
S3516 2014.06.07       N22E24           plage
12086 2014.06.08   7 3 N03E06 0013 BXO BXO location: N04E08
S3519 2014.06.08       S32W53           plage
S3522 2014.06.08   4 2 S20E09 0004   AXX  
12087 2014.06.09
2014.06.10
5 8 6 S18E71 0100 DAI DAC beta-delta

area: 0310

S3524 2014.06.09   2   S16E30 0004   BXO  
S3525 2014.06.09   1 1 N07W21 0007   AXX  
S3526 2014.06.10   1 1 N24W79 0170   AXX    
S3528 2014.06.10   1 1 N24W32 0003   AXX    
Total spot count: 79 168 95  
Sunspot number: 149 318 235  (total spot count + 10 * number of spotted regions)
Weighted SN: 117 214 141  (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): 89 111 129 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
2014.06 127.7 (1)    36.3 (2A) / 108.9 (2B) / 87.3 (2C) (70.5 projected, -2.7) (8.8)

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.