The geomagnetic field was at unsettled to very severe storm levels on June 28. The high latitude magnetometer at Andenes recorded active to major storm levels. The above 10 MeV proton flux was at background levels at the end of the day. A solar wind shock was observed at DSCOVR at 09:09 UT, most likely the arrival of the June 24 CME.
Solar flux density measured at 20h UT on 2.8 GHz was 180.7 - decreasing 7.2 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 163.12. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 163.12 on December 29, 2023). The Potsdam WDC planetary A index was 60 (STAR Ap - based on the mean of three hour interval ap indices: 60.1). Three hour interval K indices: 44468653 (planetary), 55466554 (Boulder), 66656464 (Andenes).
The background x-ray flux is at the class C1 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 21 active regions using 2K resolution (SN: 431) and in 18 active regions using 1K resolution (SN: 283) SDO/HMI images.
Region 13719 [S17W55] developed slightly and a
weak magnetic delta could be forming just northeast of the main penumbra.
Region 13720 [S06W41] decayed slowly and quietly.
Region 13721 [N25W14] decayed slowly and quietly as the main penumbra
fragmented.
Region 13722 [S13W16] developed slowly and quietly.
Region 13723 [S20E06] decayed further and produced several C flares.
C1 flares: C1.7 @ 11:19, C1.7 @ 13:49, C1.5 @ 14:14, C1.6 @ 15:34, C1.9 @
16:31 UT
Region 13725 [N21W29] was quiet and stable.
Region 13726 [S06W02] was quiet and stable.
Region 13727 [S18E20] gained some spots and produced a few C flares.
Region 13728 [S28E18] developed slowly and was mostly quiet. C1
flares: C1.5 @ 12:14, C1.7 @ 13:59, C1.7 @ 20:53 UT
Region 13729 [S04E42] gained spots and was mostly quiet. C1 flares:
C1.8 @ 03:05, C1.6 @ 04:35 UT
Region 13730 [S18W05] decayed slowly and was mostly quiet.
New region 13731 [S16E49] emerged on June 26 and was numbered by SWPC
2 days later.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9815 [N13W46] reemerged with a tiny spot.
S9830 [S07E22] was mostly quiet and stable. C1 flares: C1.6 @ 16:55
UT
S9834 [S17E63] was quiet and stable
S9838 [N24E14] was quiet and stable.
New region S9840 [N26E00] emerged with tiny spots.
New region S9841 [N05E42] emerged with tiny spots.
New region S9842 [N08E81] rotated into view with a few small spots.
C1 flares: C1.7 @ 05:17, C1.4 @ 08:17, C1.8 @ 09:25, C1.8 @ 10:38,
C1.7 @ 19:38, C1.6 @ 22:27, C1.8 @ 23:34 UT
New region S9843 [N08E44] emerged with a tiny spot.
New region S9844 [N12E09] emerged with a tiny spot.
New region S9845 [S31E29] was observed with tiny spots in an old
plage area.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C3.9 | 02:08 | northeast limb | S9842 | GOES16 | |
| C3.7 | 02:27 | 13728 | GOES16 | ||
| C2.0 | 06:30 | 13727 | GOES16 | ||
| C2.3 | 11:42 | 13728 | GOES16 | ||
| C3.2 | 14:40 | S9842 | GOES16 | ||
| C2.0 | 16:06 | S9842 | GOES16 | ||
| C2.3 | 18:45 | 13723 | GOES16 |
June 26-27: No obviously Earth directed CMEs observed.
June 28: A faint partial halo CME was observed during the first hours
of the day, the source was likely a C6.6 flare in AR 13730 at 23:47 UT on
June 27.
[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.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is very poor. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be quiet to active on June 29 and quiet on June 30. Quiet to active conditions are likely on July 1 due to the June 28 CME.
| Coronal holes (1) | Coronal mass ejections (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).
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 officially numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC, all other regions are numbered sequentially as they emerge using the STAR spot number. 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. SWPC data considered to be not sufficiently precise (location, area, classification) are colored red.
| Active region | SWPC date numbered STAR detected |
Spot count | Location at midnight | Area | Classification | SDO / HMI 4K continuum image with magnetic polarity overlays |
Comment | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| SWPC/ USAF |
Magnetic (SDO) |
SWPC | STAR | Current | Previous | ||||||
| 2K | 1K | ||||||||||
| 13719 | 2024.06.19 2024.06.19 |
3 | 13 | 5 | S16W55 | 0240 | CSO | DKO |
 |
 |
area: 0470 location: S17W55 |
| 13720 | 2024.06.19 2024.06.19 |
5 | 19 | 7 | S05W43 | 0080 | DAO | DRO |
 |
 |
location: S06W41 area: 0060 |
| S9815 | 2024.06.19 | 1 | N16W45 | 0002 | AXX |
 |
|||||
| 13725 | 2024.06.20 2024.06.23 |
12 | 4 | N18W29 | 0025 | AXX |
 |
 |
location: N21W29 | ||
| 13721 | 2024.06.21 2024.06.21 |
3 | 14 | 5 | N26W15 | 0110 | HAX | CAO |
 |
 |
area: 0100 location: N25W14 |
| 13722 | 2024.06.21 2024.06.21 |
1 | 19 | 10 | S11W17 | 0090 | HSX | DSO |
 |
 |
area: 0260 location: S13W16 |
| 13723 | 2024.06.22 2024.06.23 |
6 | 17 | 10 | S20E07 | 0050 | CRO | CRI |
 |
 |
location: S20E06 |
| 13726 | 2024.06.22 2024.06.23 |
15 | 3 | S04W10 | 0020 | BXO |
 |
 |
location: S06W02 | ||
| 13724 | 2024.06.23 | 1 | S14W17 | 0080 | HSX | SWPC split this off from AR 13722 | |||||
| 13728 | 2024.06.23 2024.06.25 |
5 | 11 | 6 | S27E17 | 0100 | DSO | DAO |
 |
 |
location: S28E18 |
| 13727 | 2024.06.24 2024.06.25 |
2 | 29 | 18 | S18E20 | 0230 | HSX | DHO |
 |
 |
area: 0450 |
| S9830 | 2024.06.24 | 7 | 2 | S07E22 | 0012 | BXO |
 |
 |
|||
| 13729 | 2024.06.25 2024.06.26 |
8 | 27 | 16 | S04E42 | 0240 | EAO | EAO |
 |
 |
area: 0520 |
| S9832 | 2024.06.25 | N07W24 |
 |
||||||||
| 13730 | 2024.06.26 2024.06.27 |
5 | 15 | 7 | S18W05 | 0050 | CAO | DRI |
 |
 |
beta-gamma |
| 13731 | 2024.06.26 2024.06.28 |
1 | 2 | 1 | S16E49 | 0010 | AXX | HRX |
 |
 |
|
| S9835 | 2024.06.26 | N51W31 | |||||||||
| S9837 | 2024.06.27 | N09E18 |
 |
||||||||
| S9838 | 2024.06.27 | 5 | 1 | N24E14 | 0008 | BXO |
 |
 |
|||
| S9839 | 2024.06.27 | S26W16 |
 |
||||||||
| 13732 | 2024.06.28 | 2 | S19E14 | 0040 | HAX | apparently SWPC has split off the westernmost spot of AR 13727. Hard to tell why | |||||
| S9840 | 2024.06.28 | 2 | 2 | N26E00 | 0010 | CRO |
 |
||||
| S9841 | 2024.06.28 | 4 | 2 | N05E42 | 0012 | CRO |
 |
||||
| S9842 | 2024.06.28 | 3 | 3 | N08E81 | 0050 | HRX |
 |
||||
| S9843 | 2024.06.28 | 2 | 1 | N08E44 | 0003 | AXX |
 |
||||
| S9844 | 2024.06.28 | 1 | N12E09 | 0002 | AXX |
 |
|||||
| S9845 | 2024.06.28 | 3 | S31E29 | 0003 | BXO |
 |
|||||
| Total spot count: | 42 | 221 | 103 | ||||||||
| Sunspot number: | 162 | 431 | 283 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 95 | 282 | 164 | (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): | 178 | 237 | 226 | ||||||||
| Month | Average solar flux | International sunspot number (WDC-SILSO) |
Smoothed sunspot number (4) | Average ap (3) |
|
|---|---|---|---|---|---|
| Measured | 1 AU | ||||
| 2014.02 | 170.3 (cycle peak) |
166.3 | 146.1 (SC24 peak) | 110.5 | 10.70 |
| 2014.04 | 143.9 | 144.8 | 112.5 | 116.4 (SC24 solar max) | 7.88 |
| 2017.09 | 91.3 | 92.3 | 43.6 | 18.2 (-1.3) | 18.22 (SC24 peak) |
| 2019.11 | 70.2 | 68.7 | 0.5 | 2.0 (-0.6) (Solar minimum using 365d smoothing: November 17, 2019) |
4.19 |
| 2019.12 | 70.8 | 68.6 | 1.6 | 1.8 (-0.2) (ISN 13 months smoothed solar minimum) |
3.22 |
| 2022.10 | 133.5 | 132.7 | 95.5 | 98.9 (+2.4) | 11.16 |
| 2022.11 | 123.4 | 120.7 | 80.5 | 101.2 (+2.3) | 9.33 |
| 2022.12 | 147.9 | 143.4 | 112.8 | 106.7 (+5.5) | 10.99 |
| 2023.01 | 182.4 | 176.6 | 144.4 | 113.3 (+6.6) | 8.73 |
| 2023.02 | 167.2 | 163.2 | 111.3 | 117.8 (+3.5) | 14.48 |
| 2023.03 | 157.2 | 155.6 | 123.3 | 121.1 (+3.3) | 14.42 |
| 2023.04 | 145.4 | 146.4 | 97.6 | 122.9 (+1.8) | 13.40 |
| 2023.05 | 155.6 | 159.2 | 137.4 | 124.2 (+1.3) | 10.67 |
| 2023.06 | 161.7 | 166.8 | 160.5 | 125.3 (+1.1) | 8.95 |
| 2023.07 | 176.4 | 182.2 | 160.0 | 124.4 (-0.9) | 8.15 |
| 2023.08 | 153.7 | 157.6 | 114.8 | 124.1 (-0.3) | 7.19 |
| 2023.09 | 154.4 | 156.0 | 134.2 | 123.9 (-0.2) | 14.26 |
| 2023.10 | 142.8 | 141.9 | 99.4 | 124.8 (+0.9) | 8.16 |
| 2023.11 | 153.5 | 150.2 | 105.4 | 127.8 (+3.0) | 12.20 |
| 2023.12 | 151.1 | 146.4 | 114.2 | (128.7 projected, +0.9) | 9.60 |
| 2024.01 | 164.6 | 159.3 | 123.0 | (127.0 projected, -1.7) | 5.46 |
| 2024.02 | 172.5 | 168.3 | 124.7 | (126.2 projected, -0.8) | 5.31 |
| 2024.03 | 154.4 | 152.9 | 104.9 | (125.6 projected, -0.6) | 11.03 |
| 2024.04 | 161.3 | 162.6 | 136.5 | (125.6 projected, -0.0) | 9.69 |
| 2024.05 | 187.7 (cycle peak) |
191.9 | 171.7 (SC25 peak) | (126.7 projected, +1.1) | 23.56 (current SC25 peak) |
| 2024.06 | 184.6 (1) | 143.2 (2A) / 153.4 (2B) / 161.1 (2C) | (125.9 projected, -0.8) | (9.8) | |
| 2024.07 | (124.2 projected, -1.7) | ||||
| 2024.08 | (122.2 projected, -2.0) | ||||
| 2024.09 | (121.0 projected, -1.2) | ||||
| 2024.10 | (119.6 projected, -1.4) | ||||
| 2024.11 | (114.5 projected, -5.1) | ||||
| 2024.12 | (109.1 projected, -5.4) | ||||
1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz
and any corrections applied to that measurement.
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) Source: WDC-SILSO, Royal Observatory
Of Belgium, Brussels
May 2024 easily became the month with the highest sunspot counts during solar cycle 25, and early June has seen no change in that pattern of many spot groups, some of which are large and complex. The next candidate for solar max is still uncertain, however, May 20-21, 2024 has all of the smoothed 365d sunspot numbers as well as the 365d smoothed solar flux signalling a peak on those days.
--------------------------------------------------------------------------------------
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.
