|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)|
The geomagnetic field was quiet to unsettled on June 21. Solar wind speed at SOHO ranged between 276 and 360 km/s. A weak solar wind shock was observed at 15:50 UT at SOHO, the arrival of the CME observed on June 18. Another sudden increase in solar wind speed was recorded near 04:45 UT on June 22, likely the arrival of the June 19 CME. Following the arrival of this second CME the interplanetary magnetic field has swung more strongly southwards and minor to major geomagnetic storming will be possible.
Solar flux at 20h UTC on 2.8 GHz was 131.7 (increasing 35.2 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 128.7. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.4). Three hour interval K indices: 11001323 (planetary), ******** (Boulder).
The background x-ray flux is at the class B6 level.
At the time of counting spots (see image time), spots were observed in 6 active regions using 2K resolution (SN: 144) and 4 active regions using 1K resolution (SN: 84) SDO images on the visible solar disk.
Region 12367 [S20W65] became a compact region and
could produce further M class events before rotating out of view.
Region 12371 [N11E01] did not display major changes. With a large magnetic delta in the trailing penumbra further M class events are likely. A major flare is possible.
Spotted regions not numbered (or interpreted differently) by SWPC:
S4557 [N15W29] was quiet and stable.
S4563 [S09E34] was quiet and stable.
New region S4564 [N14E75] rotated into view.
New region S4565 [S10E22] was observed with a penumbra spot.
Minor update at 18:50 UT on June 22: AR 12371 produced a major M6.5 flare peaking at 18:23 UT. A few minutes earlier, at 18:00 UT, a very strong solar wind shock was observed at SOHO. This is the arrival of the CME observed on June 21, a transit time of just 40 hours. The interplanetary magnetic field has swung extremely strongly southwards and this will likely result in severe geomagnetic storming for the remainder of today and tomorrow.
|Magnitude||Peak time (UTC)||Location||AR||Recorded by||Comment|
|M2.6 (LDE)||02:49||12371||GOES15||full halo CME|
June 19: A partial halo CME caused by a large filament eruption in the
suthern hemisphere could reach Earth on June 22.
June 20: No obviously Earth directed CMEs were observed.
June 21: A halo CME was observed after an M2 flare in AR 12371 early in day. The CME will likely reach Earth on June 23.
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 hemispere coronal hole (CH673) was in an Earth facing position on June 19-20. CH673 did not cause a significant geomagnetic disturbance during the previous rotation. CH673 decreased in size June 16-18, but became larger following a filament eruption in the southern hemisphere on June 19.
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.
The geomagnetic field is expected to be quiet to major storm on June 22-24 due to the arrival of the CMEs observed on June 19 and 21. The CME observed early on June 21 will likely arrive on June 23 and could increase the disturbance level to major storm. A high speed stream from CH673 could complicate the geomagnetic disturbance situation on June 23.
|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.
(Click on image for 2K resolution) Compare to the previous day's 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
|Spot count||Location at midnight||Area||Classification||SDO / HMI 4K continuum
image with magnetic polarity overlays
|Total spot count:||59||84||44|
|Sunspot number:||79||144||84||(total spot count + 10 * number of spotted regions)|
|Weighted SN:||74||99||59||(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):||47||50||46||k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for MSN 2K, k = 0.55 for MSN 1K (MSN=Magnetic Sunspot Number)|
|Month||Average solar flux||International sunspot number
|Smoothed sunspot number||Average
|166.3||102.3 (cycle peak)||78.4 (+1.1)||10.70|
|2014.04||143.9||144.8||84.7||81.9 (+1.1) (solar max)||7.88|
|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||(129.4)||64.6 (2A) / 92.3 (2B) / 61.5 (2C)||(49.6 projected, -2.8)||(7.9)|
1) Running average based on the daily 20:00 UTC observed solar flux value at
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.