Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 15, 2016 at 03:55 UT.

Charts (* = updated daily Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data from 2003.01 (June 2, 2016)
Solar cycle Solar cycles 23-24 (June 1, 2016) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (June 1, 2016) Noon SDO sunspot count 1K / 4K (*)
  Solar cycles 1-24 (July 17, 2015) POES auroral activity level October 2009 - December 2012
  Comparison of cycles 21, 22, 23 and 24 (June 1, 2016) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12, 13, 14, 16 and 24 (June 1, 2016) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (May 20, 2016)  

Recent activity

The geomagnetic field was quiet to major storm on June 14. Solar wind speed at SOHO ranged between 409 and 613 km/s. A co-rotating interaction region associated with the eastern part of CH739 and CH740 caused geomagnetic storming during the last part of the day.

Solar flux at 20h UTC on 2.8 GHz was 87.6 (decreasing 14.7 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 92.1. The Potsdam WDC planetary A index was 16 (STAR Ap - based on the mean of three hour interval ap indices: 15.6). Three hour interval K indices: 22112263 (planetary), 22233343 (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 6 active regions using 2K resolution (SN: 85) and 6 active regions using 1K resolution (SN: 77) SDO images on the visible solar disk.

Region 12553 [S06E18] was quiet and stable.
Region 12554 [N08W72] decayed slowly and quietly.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5326 [S11W10] reemerged with a few tiny spots.
S5330
[N08W12] was quiet and stable.
New region S5331 [N04E26] was observed with tiny spots.
New region S5332 [S08W29] emerged with several spots.

C2+ flares:

Magnitude Peak time (UT) Location AR Recorded by Comment
           

Flare activity (SDO/EVE/ESP XRS-B proxy)

Coronal mass ejections (CMEs)

June 12-14: No obviously Earth directed CMEs were observed in available LASCO 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 recurrent northern hemisphere coronal hole (CH739) rotated across the central meridian on June 8-9 and has another extension which was in a potentially geoeffective position on June 12-14. A recurrent trans equatorial coronal hole (CH740) was in an Earth facing position on June 11-15.

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 to active on June 15-17 due to effects from CH739 and CH740 with a chance of minor storm intervals on the first day.

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). 4K 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 overlays
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
S5321 2016.06.08       N13W28            
12553 2016.06.09
2016.06.10
1 6 3 S07E18 0290 HHX CKO  
12554 2016.06.10
2016.06.11
5 7 4 N08W72 0100 DSO CAO  
S5326 2016.06.12   3 3 S11W10 0010   BXO    
S5327 2016.06.12       N18W25            
S5328 2016.06.12       S18E22            
S5329 2016.06.12       S32E10            
S5330 2016.06.13   2 1 N08W12 0004   BXO  
S5331 2016.06.14   2 2 N04E26 0006   BXO    
S5332 2016.06.14   5 4 S08W29 0020   CRO    
Total spot count: 6 25 17  
Sunspot number: 26 85 77  (total spot count + 10 * number of spotted regions)
Weighted SN: 21 43 35  (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): 29 47 62 k * (sunspot number)
As of May 7, 2016: k = 1.1 for SWPC, k = 0.55 for MSN 2K, k = 0.80 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO) (4)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (cycle peak) 110.5 (+1.2) 10.70
2014.04 143.9 144.8 112.5 116.4 (+2.1) (solar max) 7.88
2015.03 125.9 124.6 54.5 82.2 (-3.9) 16.14
2015.04 128.8 129.7 75.3 78.9 (-3.3) 10.73
2015.05 120.0 122.6 88.8 76.1 (-2.8) 8.29
2015.06 122.3 126.1 66.5 72.1 (-4.0) 13.15
2015.07 107.0 110.8 66.4 68.3 (-3.8) 8.83
2015.08 105.4 108.0 64.6 66.4 (-1.9) 14.58
2015.09 101.7 102.7 78.1 66.0 (-0.4) 15.78
2015.10 104.1 103.3 61.7 64.4 (-1.6) 14.02
2015.11 109.3 106.9 63.2 61.4 (-3.0) 12.09
2015.12 113.1 109.5 57.7 (59.1 projected, -2.3) 14.29
2016.01 103.4 100.1 56.6 (57.5 projected, -1.6) 9.4
2016.02 103.6 101.0 57.2 (55.1 projected, -2.4) 9.9
2016.03 91.5 90.6 54.9 (52.2 projected, -2.9) 10.58
2016.04 93.3 94.0 38.0 (49.4 projected, -2.8) 9.03
2016.05 93.0 95.3 52.1 (47.6 projected, -1.8) 11.65
2016.06 (84.4)   8.5 (2A) / 18.3 (2B) / 35.9 (2C) (45.8 projected, -1.8) (8.7)

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).
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.
4) Updated to new data set from WDC-SILSO on July 1, 2015

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 Universal Time. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.