Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 7, 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 on June 6. Solar wind speed at SOHO ranged between 333 and 350 km/s.

Solar flux at 20h UTC on 2.8 GHz was 133.0 (decreasing 19.1 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 139.2. The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.0). Three hour interval K indices: 21001212 (planetary), 21012322 (Boulder).

The background x-ray flux is at the class B4 level.

At the time of counting spots (see image time), spots were observed in 13 active regions using 2K resolution (SN: 292) and 13 active regions using 1K resolution (SN: 221) SDO images on the visible solar disk.

Region 12077 [S03W22] developed significantly and could produce C flares.
Region 12079 [N12E00] was quiet and stable.
Region 12080 [S12E18] developed further and has 2 magnetic delta structures in the trailing spot section. Further M class flaring is possible.
Region 12081 [N05E10] was quiet and stable.
Region 12082 [N17E27] developed quickly and could produce M class flares.
Region 12083 [S12W77] decayed slowly and quietly.
New region 12084 [S11W12] emerged with several spots.
New region 12085 [S20E25] emerged on June 5 and developed quickly on June 6 when it was numbered by SWPC. A minor M class flare is possible.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3492 [N11W23] reemerged with penumbra spots.
S3499
[S10E09] reemerged with penumbra spots.

New region S3507 [N12W11] was observed with a penumbra spot.
New region S3509 [S15W68] emerged with penumbra spots.
New region S3510 [S12E35] was observed with penumbra spots.

C2+ Flares (GOES):

Magnitude Time (UTC) Location AR
C3.6 13:11 S12E25 12080
C2.0 13:27   12080
M1.4 19:31 S12E25 12080
C3.4 22:25 S13E23 12080

Coronal mass ejections (CMEs)

June 5-6: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
June 4: A large filament eruption in the southeast quadrant during the evening was associated with an asymmetric full halo CME.

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

An extension (CH621) of a large southern hemisphere coronal hole may have been in an Earth facing position on June 6. A small trans equatorial coronal hole (CH622) could rotate into an Earth facing position on June 8.

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 quiet to active on June 7-8 due to effects from the June 4 CME. Mostly quiet conditions are likely on June 9.

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 7 19 11 S04W24 0090 DSO DAI

area: 0190

location: S03W22

12078 2014.05.30
2014.06.01
1     S20W57 0000 AXX       spotless

real location: S19W53

12079 2014.05.31
2014.06.01
1 8 5 N12W00 0090 HSX HSX area: 0180
S3492 2014.05.31   3 2 N11W23 0010   BXO    
12081 2014.06.01
2014.06.04
  4 2 N05E04 0010   BXO  
S3495 2014.06.01       S10W40           plage
S3496 2014.06.02       N17W00           plage
12080 2014.06.02
2014.06.03
15 42 20 S12E18 0160 DAI EAC beta-gamma-delta

area: 0320

S3499 2014.06.03   4 3 S10E09 0010   AXX    
S3500 2014.06.04       S21W57         plage
S3501 2014.06.04       S23E16         plage
S3502 2014.06.04       S12W01           plage
12082 2014.06.04
2014.06.05
18 26 16 N17E26 0170 DAC DKC area: 0500
12083 2014.06.04
2014.06.05
2 3 2 S12W76 0010 BXO CRO  
S3505 2014.06.05       S15E46        
12085 2014.06.05
2014.06.06
6 29 16 S21E24 0020 DRI DAC  
12084 2014.06.06 2 15 8 S12W13 0010 BXO DRI    
S3507 2014.06.06   1 1 N12W11 0004   AXX    
S3509 2014.06.06   4 2 S15W68 0012   BXO    
S3510 2014.06.06   4 3 S12E35 0010   AXX    
Total spot count: 52 162 91  
Sunspot number: 132 292 221  (total spot count + 10 * number of spotted regions)
Weighted SN: 85 198 127  (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): 79 102 122 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
2014.06 114.5 (1)    20.8 (2A) / 92.0 (2B) / 88.0 (2C) (70.5 projected, -2.7) (5.8)

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.