Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 14, 2015 at 06:30 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 1, 2015)
Solar cycle Solar cycles 23-24 (June 1, 2015) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (June 1, 2015) Noon SDO sunspot count 1K Reference: 4K (large file) (*)
  Solar cycles 1-20 POES auroral activity level October 2009 - December 2012
  Comparison of cycles 21, 22, 23 and 24 (June 1, 2015) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 10, 12, 13, 14, 16 and 24 (June 1, 2015) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs solar cycles (June 8, 2015)  

Recent activity

The geomagnetic field was quiet to unsettled on June 13 under the influence of a high speed stream associated with CH672. Solar wind speed at SOHO ranged between 430 and 489 km/s.

Solar flux at 20h UTC on 2.8 GHz was 136.1 (increasing 16.5 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 126.6. The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 7.9). Three hour interval K indices: 32222222 (planetary), 33433323 (Boulder).

The background x-ray flux is at the class B9 level.

At the time of counting spots (see image time), spots were observed in 15 active regions using 2K resolution (SN: 232) and 10 active regions using 1K resolution (SN: 141) SDO images on the visible solar disk.

Region 12360 [N15W83] rotated partly out of view and was very active during the day producing many C flares and an M class event. A major flare is possible while the region is at and just behind the northwest limb.
Region 12361 [N21W48] decayed slowly and quietly.
Region 12362 [N07W50] decayed slowly and quietly.
Region 12364 [S05W31] was quiet and stable.
Region 12365 [S12W32] was quiet and stable. The region has weak polarity intermixing.
Region 12366 [N18W35] decayed slowly and quietly.
Region 12367 [S20E45] gained penumbral area and was quiet. A minor M class flare is possible.
New region 12368 [S07W49] emerged on June 9 and was numbered by SWPC 4 days later as the region decayed.
New region 12369 [N05E57] rotated into view on June 12 and was numbered the next day as the region began to decay.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4531 [S10W13] reemerged with penumbra spots.
S4541 [N16W30] decayed slowly and quietly.
S4543 [S05E26] lost the leader spot and gained trailing penumbra spots.
S4544 [S17W33] developed slowly and quietly.
S4545 [N18E38] developed slowly and quietly.
New region S4548 [N08E06] emerged with a few spots.

C2+ flares:

Magnitude Peak time (UTC) Location AR Recorded by Comment
C5.9 00:33 N14W74 12360 GOES15  
C3.5 01:42   12360 GOES15  
C5.9 02:37 N15W72 12360 GOES15  
C3.8 05:38   12360 GOES15  
C4.3 06:25 N14W73 12360 GOES15  
C4.0 07:00   12360 SDO/EVE  
M1.3 07:29 N11W78 12360 GOES15  
C5.8 09:45 N11W77 12360 GOES15  
C2.4 10:29   12360 GOES15  
C2.2 12:50 N10W78 12360 GOES15  
C4.9 14:37 N11W80 12360 GOES15  
C2.6 19:27 N14W84 12360 GOES15  
C2.5 21:25 N14W84 12360 GOES15  
C2.2 23:14   12360 GOES15  

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

Coronal mass ejections (CMEs)

June 11-13: No obviously Earth directed CMEs were observed.

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 trans equatorial coronal hole (CH672) rotated across the central meridian on June 10-11.

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 fair.

Forecast

The geomagnetic field is expected to be quiet to active on June 14 with a chance of minor storm intervals due to effects from CH672 and quiet to unsettled on June 15-16.

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 overlays
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12360 2015.06.01
2015.06.03
6 3 2 N15W82 0150 EAI DAO

area: 0270

12361 2015.06.03
2015.06.04
  3   N18W60 0006   BXO location: N21W48
12362 2015.06.03
2015.06.04
1 1 1 N08W51 0010 HRX HRX

 

12365 2015.06.05
2015.06.06
7 16 8 S15W33 0090 CAO CAO

beta-gamma

SWPC is incorrectly including AR S4544 in this region

location: S12W32

12364 2015.06.05
2015.06.06
  2   S07W34 0005   AXX

 

12366 2015.06.06
2015.06.07
10 6 5 N17W33 0060 CAI CRO SWPC is including the spots of AR S4541
S4530 2015.06.07       N10W37          
S4531 2015.06.08   3   S10W13 0007   AXX    
S4532 2015.06.09       N07W37            
S4533 2015.06.09       S32W02            
S4534 2015.06.09       S22W53            
12368 2015.06.09
2015.06.13
  1   S06W52 0001   AXX  
12367 2015.06.10
2015.06.11
12 23 12 S20E44 0300 EKI DKI

area: 0520

S4538 2015.06.11       N18W21            
S4539 2015.06.11       S10E40            
12369 2015.06.12
2015.06.13
1 2 1 N06E55 0000   AXX area: 0006
S4541 2015.06.12   6 5 N16W30 0040   DRO split off from AR 12366
S4542 2015.06.12       N11W08          
S4543 2015.06.12   2   S05E26 0005   AXX  
S4544 2015.06.12   6 3 S17W33 0020   CRO  
S4545 2015.06.12   6 3 N18E38 0015   BXO  
S4546 2015.06.12       S33W52          
S4548 2015.06.13   2 1 N08E06 0009   CRO    
Total spot count: 37 82 41  
Sunspot number: 97 232 141  (total spot count + 10 * number of spotted regions)
Weighted SN: 65 117 76  (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): 58 81 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
2014.01 157.4 152.4 81.8 77.3 (+1.3) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) 78.4 (+1.1) 10.70
2014.03 149.9 148.5 91.9 80.8 (+2.4) 4.88
2014.04 143.9 144.8 84.7 81.9 (+1.1) (solar max) 7.88
2014.05 129.7 132.9 75.2 80.5 (-1.4) 5.75
2014.06 122.0 125.8 71.0 79.7 (-0.8) 6.72
2014.07 137.4 141.8 72.5 78.5 (-1.2) 4.50
2014.08 124.7 127.9 74.7 75.5 (-3.0) 7.71
2014.09 146.6 148.1 87.6 70.8 (-4.7) 9.78
2014.10 153.4 152.9 60.6 67.3 (-3.5) 8.96
2014.11 154.8 151.4 70.1 65.4 (-1.9) 9.33
2014.12 158.7 153.8 78.0 (63.5 projected, -1.9) 11.24
2015.01 141.9 137.3 67.0 (61.3 projected, -2.2) 9.46
2015.02 129.1 126.0 44.8 (59.6 projected, -1.7) 9.92
2015.03 125.9 124.6 38.4 (57.2 projected, -2.4) 16.14
2015.04 128.8 129.7 54.4 (54.6 projected, -2.6) 10.73
2015.05 120.0 122.6 58.8 (52.4 projected, -2.2) 8.29
2015.06 (126.0)   40.3 (2A)/ 93.0 (2B) / 65.1 (2C) (49.6 projected, -2.8) (7.9)

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.