The geomagnetic field was at quiet levels on August 26. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. The above 10 MeV proton flux was at background levels at the end of the day.
Solar flux density measured at 17h UT on 2.8 GHz was 232.2 - increasing 9.1 over the previous solar rotation. There was no measurement at 20:00 UT. (Centered 1 year average SF at 1 AU - 183 days ago: 172.04. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 172.04 on February 26, 2024). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 3.8). Three hour interval K indices: 21011101 (planetary), 21012301 (Boulder), 33013312 (Andenes).
The background x-ray flux is at the class C2 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 16 active regions using 2K resolution (SN: 346) and in 14 active regions using 1K resolution (SN: 239) SDO/HMI images.
AR 13790 [S11W74] decayed slowly and was mostly
quiet.
AR 13792 [S18W57] was quiet and stable.
AR 13793 [N22W72] decayed slowly and quietly.
AR 13796 [S03W39] developed a magnetic delta
configuration in a southern trailing spot section. M class flaring is
likely.
AR 13798 [N06W18] was quiet and stable.
AR 13799 [S10W07] decayed slowly and was mostly quiet.
AR 13800 [S27W22] gained area and the magnetic delta configuration in
the central spot section increased in size.
AR 13801 [N08E13] was mostly quiet and stable.
AR 13802 [N13W49] was quiet and stable.
New AR 13803 [N14E68] rotated into view on August 25 and was numbered
the next day by SWPC.
New AR 13804 [S25E62] rotated into view on August 25 and received its
NOAA number the following day.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S10033 [S04W23] was quiet and stable.
S10045 [N09W30] was quiet and stable.
S10048 [N13W07] was quiet and stable.
New region S10059 [N08E63] was observed with tiny spots in an old
plage area.
New region S10060 [S07E80] rotated into view with a tiny spot.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C2.4 | 01:21 | 13796 | GOES16 | ||
| C3.7 | 02:47 | 13796 | GOES16 | ||
| C3.9 | 03:05 | behind the southeast limb | GOES16 | ||
| C3.9 | 03:16 | 13800 | GOES16 | ||
| C3.4 | 03:46 | 13800 | GOES16 | ||
| C3.8 | 04:31 | 13796 | GOES16 | ||
| C3.8 | 04:40 | 13800 | GOES16 | ||
| C6.9 | 05:28 | S04W24 | 13796 | GOES16 | |
| C8.0 | 05:53 | 13796 | GOES16 | ||
| C7.9 | 06:24 | 13796 | GOES16 | ||
| C5.7 | 07:14 | 13796 | GOES16 | ||
| C9.0 | 08:11 | 13796 | GOES16 | ||
| C6.0 | 09:41 | 13796 | GOES16 | ||
| C4.2 | 10:18 | 13796 | GOES16 | ||
| C9.0 | 11:03 | 13796 | GOES16 | ||
| C4.7 | 11:30 | 13796 | GOES16 | ||
| M1.4 | 11:40 | 13796 | GOES16 | ||
| C5.6 | 12:58 | 13796 | GOES16 | ||
| C3.9 | 13:15 | 13796 | GOES16 | ||
| C3.3 | 13:34 | 13796 | GOES16 | ||
| C3.4 | 16:15 | 13799 | GOES16 | ||
| C4.2 | 16:34 | 13796 | GOES16 | ||
| C3.4 | 16:46 | 13796 | GOES16 | ||
| C3.2 | 17:20 | 13796 | GOES16 | ||
| C3.2 | 17:48 | S10033 | GOES16 | ||
| C2.4 | 18:17 | S10033 | GOES16 | ||
| C3.6 | 18:47 | 13796 | GOES16 | ||
| C2.7 | 19:33 | 13800 | GOES16 | ||
| C2.8 | 20:14 | 13799 | GOES16 | ||
| C4.0 | 20:22 | 13800 | GOES16 | ||
| C2.5 | 21:19 | 13796 | GOES16 | ||
| C2.6 | 23:10 | 13796 | GOES16 |
August 24-26: No obviously Earth directed CMEs were observed.
[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 poor to fair. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be at quiet levels on August 27-30.
| 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 | ||||||||||
| 13790 | 2024.08.15 2024.08.15 |
12 | 9 | 7 | S13W74 | 0350 | DKC | DKC |
 |
 |
area: 0720 location: S11W74 |
| 13792 | 2024.08.16 2024.08.16 |
3 | 7 | 2 | S17W59 | 0310 | HHX | CHO |
 |
 |
location: S18W57 area: 0400 |
| 13793 | 2024.08.16 2024.08.17 |
1 | N22W72 | 0002 | AXX |
 |
 |
|
|||
| 13794 | 2024.08.16 2024.08.17 |
2 | N19W92 | 0030 | CAO |
 |
rotated out of view | ||||
| 13796 | 2024.08.17 2024.08.18 |
18 | 27 | 17 | S04W40 | 0360 | EKI | DKC |
 |
 |
beta-gamma-delta location: S03W39 area: 0500 |
| 13795 | 2024.08.17 2024.08.18 |
N09W38 | location: N02W35 | ||||||||
| S10033 | 2024.08.18 | 7 | 2 | S04W23 | 0015 | AXX |
 |
 |
|||
| 13798 | 2024.08.19 2024.08.19 |
1 | 2 | 2 | N06W18 | 0040 | HSX | HSX |
 |
 |
area: 0100 |
| 13799 | 2024.08.20 2024.08.21 |
17 | 36 | 20 | S10W04 | 0360 | EKI | DHI |
 |
 |
area: 0570 location: S10W07 |
| 13800 | 2024.08.20 2024.08.22 |
20 | 42 | 21 | S27W20 | 0360 | EKI | EKC |
 |
 |
beta-gamma-delta location: S27W22 area: 0570 |
| S10039 | 2024.08.20 | N30W55 | |||||||||
| 13801 | 2024.08.21 2024.08.22 |
11 | 28 | 14 | N08E13 | 0130 | DSO | DSI |
 |
 |
beta-gamma area: 0260 |
| S10043 | 2024.08.21 | N33W51 | |||||||||
| S10044 | 2024.08.21 | N02W55 | |||||||||
| S10045 | 2024.08.21 | 5 | 2 | N09W30 | 0010 | BXO |
 |
||||
| S10046 | 2024.08.22 | N13E05 | |||||||||
| S10047 | 2024.08.22 | N21E10 |
 |
||||||||
| S10048 | 2024.08.22 | 3 | N13W07 | 0005 | AXX |
 |
 |
||||
| S10049 | 2024.08.22 | S20E06 | |||||||||
| S10050 | 2024.08.22 | S29W19 | |||||||||
| 13802 | 2024.08.23 2024.08.25 |
3 | 7 | 4 | N13W49 | 0010 | BXO | CRO |
 |
 |
area: 0020 |
| S10053 | 2024.08.24 | N18W46 | |||||||||
| S10054 | 2024.08.24 | S08E31 | |||||||||
| S10055 | 2024.08.24 | S33W21 | |||||||||
| S10056 | 2024.08.24 | N35W59 | |||||||||
| 13803 | 2024.08.25 2024.08.26 |
4 | 7 | 4 | N12E69 | 0050 | DAO | DAO |
 |
 |
location: N14E68 area: 0200 |
| 13804 | 2024.08.25 2024.08.26 |
1 | 1 | 1 | S25E63 | 0030 | HSX | HSX |
 |
 |
location: S25E62 |
| S10059 | 2024.08.26 | 3 | 2 | N08E63 | 0010 | AXX |
 |
||||
| S10060 | 2024.08.26 | 1 | 1 | S07E80 | 0003 | AXX |
 |
||||
| Total spot count: | 92 | 186 | 99 | ||||||||
| Sunspot number: | 202 | 346 | 239 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 167 | 259 | 172 | (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): | 222 | 190 | 191 | ||||||||
| 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 |
| 2022.11 | 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 | 124.6 (-0.7) | 8.15 |
| 2023.08 | 153.7 | 157.6 | 114.8 | 124.3 (-0.3) | 7.19 |
| 2023.09 | 154.4 | 156.0 | 134.2 | 124.0 (-0.3) | 14.26 |
| 2023.10 | 142.8 | 141.9 | 99.4 | 124.8 (+0.8) | 8.16 |
| 2023.11 | 153.5 | 150.2 | 105.4 | 127.8 (+3.0) | 12.20 |
| 2023.12 | 151.1 | 146.4 | 114.2 | 129.4 (+1.6) | 9.60 |
| 2024.01 | 164.6 | 159.3 | 126.0 | 131.1 (+1.7) | 5.46 |
| 2024.02 | 172.5 | 168.3 | 123.0 | (137.4 projected, +6.3) | 5.31 |
| 2024.03 | 154.4 | 152.9 | 103.7 | (144.1 projected, +6.7) | 11.03 |
| 2024.04 | 161.3 | 162.6 | 136.5 | (148.2 projected, +4.1) | 9.69 |
| 2024.05 | 187.7 | 191.9 | 171.7 | (152.9 projected, +4.7) | 23.56 (SC25 peak) |
| 2024.06 | 184.3 | 190.2 | 164.2 | (156.9 projected, +4.0) | 10.24 |
| 2024.07 | 196.6 (cycle peak) |
203.0 | 196.5 (SC25 peak) | (158.7 projected, +1.8) | 7.13 |
| 2024.08 | 251.7 (1) | 177.0 (2A) / 211.0 (2B) / 227.4 (2C) [projected ISN: 222] |
(159.1 projected, +0.4) | (15.5) | |
| 2024.09 | (161.0 projected, +1.9) | ||||
| 2024.10 | (162.8 projected, +1.8) | ||||
| 2024.11 | (160.8 projected, -2.0) | ||||
| 2024.12 | (156.4 projected, -4.4) | ||||
| 2025.01 | (150.3 projected, -6.1) | ||||
| 2025.02 | (143.0 projected, -7.3) | ||||
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
Sunspot counts in July 2024 were the highest we've seen for a single month during solar cycle 25. The first part of August has seen very high sunspot counts, and there more than a remote possibility that we'll see activity in August approaching the most active months of solar cycle 23. With at least 4 consecutive months of high sunspot counts the projected peak for the smoothed ISN (365 days smoothing) has increased significantly to above 160. The month of the peak is currently likely to occur sometime between July and November 2024.
--------------------------------------------------------------------------------------
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.
