Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 17, 2014 at 04:35 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 16. Solar wind speed at SOHO ranged between 346 and 388 km/s.

Solar flux at 20h UTC on 2.8 GHz was 116.8 (decreasing 0.4 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 140.5. The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.1). Three hour interval K indices: 11112111 (planetary), 01112322 (Boulder).

The background x-ray flux is at the class B5 level.

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 174) and 8 active regions using 1K resolution (SN: 117) SDO images on the visible solar disk.

Region 12087 [S18W08] gained spots and penumbral area and produced several C flares. A minor M class flare is possible.
Region 12089 [N18W51] developed slowly and has polarity intermixing. C and M class flares are possible.
Region 12090 [N25E03] was quiet and stable.
Region 12092 [S17E06] was quiet and stable.
New region 12093 [S10E67] rotated into view on June 15 with SWPC numbering the region the next day.
New region 12094 [S18E71] rotated into view on June 15 and was numbered by SWPC the following day.

Spotted regions not numbered (or interpreted differently) by SWPC:
New region S3544 [S05W60] emerged early in the day with spots, then decayed slowly.
New region S3545 [S14W04] emerged with penumbra spots.
New region S3546 [S08W21] emerged with penumbra spots.
New region S3547 [N16E33] emerged with a penumbra spot.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
C8.5 (LDE) 02:15   12085
C2.8/1F 07:42 N18W42 12089
C2.3 18:07 S20W02 12087
C2.9 19:18 S20W02 12087
C3.2 20:22 S20W02 12087
C2.3 21:51 N17W50 12089

Coronal mass ejections (CMEs)

June 15: A CME was observed after the C5 event in AR 12092. While the core of this fairly narrow CME was headed to the southeast, there could be a weak Earth directed component.
June 14, 16
: 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

No obvious coronal holes are currently in or near Earth facing positions.

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 to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be mostly quiet on June 16-18.

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
12089 2014.06.07
2014.06.11
15 24 9 N18W52 0270 DKC DKC

area: 0500

S3516 2014.06.07       N22W54           plage
12086 2014.06.08       N01W77            
12087 2014.06.09
2014.06.10
9 19 11 S18W08 0110 CSI CSI area: 0260
S3524 2014.06.09       S16W49           plage
12090 2014.06.10
2014.06.11
1 4 3 N24E02 0120 HSX CSO area: 0170

location: N25E03

12091 2014.06.11
2014.06.12
      S08W57           plage
12092 2014.06.11
2014.06.12
  10 3 S20E05 0020   BXO  
S3531 2014.06.11       S22W03           plage
S3532 2014.06.11       S29W26           plage
S3536 2014.06.13       N18W50           plage
S3537 2014.06.13       S19W38           plage
S3538 2014.06.15       S08E54         plage
12093 2014.06.15
2014.06.16
5 9 8 S12E62 0070 DSO DAO location: S10E67
12094 2014.06.15
2014.06.16
1 1 1 S18E67 0060 HSX HAX area: 0100
S3541 2014.06.15       S15E21         plage
S3542 2014.06.15       S09E01         plage
S3543 2014.06.15       N12W35         plage
S3544 2014.06.16   1 1 S05W60 0005   AXX    
S3545 2014.06.16   3   S14W04 0005   BXO    
S3546 2014.06.16   2 1 S08W21 0004   AXX    
S3547 2014.06.16   1   N16E33 0002   AXX    
Total spot count: 31 74 37  
Sunspot number: 81 174 117  (total spot count + 10 * number of spotted regions)
Weighted SN: 61 104 61  (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): 49 61 64 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
2014.06 135.2 (1)   68.6 (2A) / 128.6 (2B) / 80.2 (2C) (70.5 projected, -2.7) (7.1)

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.