The geomagnetic field was at quiet to active levels on October 28 due to effects from the October 26 CME. Solar wind speed at SOHO ranged between 479 and 592 km/sec. The high latitude magnetometer at Andenes recorded quiet to major storm levels. The above 10 MeV proton flux was at 71 pfu at the end of the day, slowly decreasing.
Solar flux density measured at 20h UT on 2.8 GHz was 265.6 - decreasing 8.8 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 182.47. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 182.47 on April 30, 2024). The Potsdam WDC planetary A index was 12 (STAR Ap - based on the mean of three hour interval ap indices: 11.5). Three hour interval K indices: 32222342 (planetary), 31323432 (Boulder), 42322463 (Andenes).
The background x-ray flux is at the class C3 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 17 active regions using 2K resolution (SN: 453) and in 14 active regions using 1K resolution (SN: 267) SDO/HMI images.
AR 13863 [S09W76] decayed slowly and quietly.
AR 13866 [S13W48] decayed slowly and quietly.
AR 13868 [S11W32] was quiet and stable.
AR 13869 [S18W08] was mostly quiet. The leader spot of AR 13872 is
approaching the largest trailing spot of AR 13869 and there 2 regions could
merge within a few days.
AR 13872 [S18W03] was quiet and stable.
AR 13873 [S15E05] lost the magnetic delta configuration in the
leading penumbra and produced the only M flare of the day.
AR 13874 [N24W32] decayed slowly and was mostly quiet.
AR 13875 [N27W14] decayed slowly and quietly.
AR 13876 [S05W19] developed early in the day and a magnetic delta
configuration formed. Decay was observed after noon and the magnetic delta
disappeared.
AR 13877 [S16E24] was quiet and stable.
AR 13878 [N15E52] still has a magnetic delta configuration in the trailing penumbra. A major flare is possible.
New AR 13879 [N14E74] rotated partly into view on October 28 and was
numbered the next day by SWPC.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S10278 [S22E08] was quiet and stable.
S10279 [N15W09] was quiet and stable.
S10292 [N18E32] was quiet and stable.
New region S10297 [S12E31] emerged with tiny
spots.
New region S10298 [S13E81] rotated into view with a tiny spot.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C4.1 | 00:39 | 13878 | GOES16 | ||
| C3.4 | 02:17 | 13878 | GOES16 | ||
| C3.9 | 04:40 | 13878 | GOES16 | ||
| C3.6 | 05:12 | 13874 | GOES16 | ||
| C5.0 | 08:00 | 13878 | GOES16 | ||
| C5.3 | 08:19 | 13878 | GOES16 | ||
| C4.4 | 08:53 | 13878 | GOES16 | ||
| C3.9 | 09:38 | 13878 | GOES16 | ||
| C3.7 | 09:57 | 13878 | GOES16 | ||
| C4.0 | 12:04 | 13878 | GOES16 | ||
| C3.0 | 12:19 | 13878 | GOES16 | ||
| C2.8 | 13:02 | 13878 | GOES16 | ||
| C2.5 | 13:30 | 13876 | GOES16 | ||
| C3.8 | 14:37 | 13876 | GOES16 | ||
| C5.5 | 15:49 | behind southwest limb | GOES16 | ||
| M1.1/1F | 16:33 | 13873 | GOES16 | ||
| C3.9 | 21:39 | 13869 | GOES16 | ||
| C3.4 | 22:47 | 13878 | GOES16 |
October 27-28: No obviously Earth directed CMEs were observed.
October 29: A large filament in the southwestern quadrant erupted
around noon. A partial halo CME was observed afterwards, and there is a
slight chance components of the CME could reach Earth on November 1-2.
[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 negative polarity southern hemisphere coronal hole (CH1250) was Earth facing on October 24-25. A positive polarity northern hemisphere coronal hole (CH1251) could rotate across the central meridian on October 30-31.
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 October 30 due to lingering CME effects. Mostly quiet levels are likely on October 31 - November 1. Should the October 29 CME reach Earth the geomagnetic field could become unsettled to active November 1-2. Quiet to unsettled levels are possible on November 2-3 due to effects from CH1251.
| 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 | ||||||||||
| 13863 | 2024.10.17 2024.10.19 |
3 | 4 | 2 | S08W77 | 0010 | AXX | BXO |
 |
 |
location: S09W76 |
| 13862 | 2024.10.18 2024.10.19 |
S15W87 | |||||||||
| 13865 | 2024.10.19 2024.10.20 |
S22W58 | location: S22W60 | ||||||||
| 13864 | 2024.10.19 2024.10.20 |
N25W79 | location: N25W69 | ||||||||
| 13866 | 2024.10.20 2024.10.21 |
1 | S12W50 | 0001 | AXX |
 |
 |
||||
| S10261 | 2024.10.20 | N17W55 |
 |
||||||||
| 13867 | 2024.10.20 2024.10.21 |
S15W80 | location: S21W72 | ||||||||
| 13868 | 2024.10.21 2024.10.21 |
1 | 5 | 1 | S11W32 | 0150 | HSX | CSO |
 |
 |
area: 0250 |
| S10265 | 2024.10.21 | S25W56 | |||||||||
| S10266 | 2024.10.21 | N09W56 | |||||||||
| 13869 | 2024.10.22 2024.10.23 |
27 | 45 | 20 | S16W12 | 0280 | EKC | EAI |
 |
 |
beta-gamma location: S18W08 |
| 13875 | 2024.10.23 2024.10.24 |
3 | 12 | 7 | N29W19 | 0010 | BXO | BXO |
 |
 |
location: N27W14 |
| S10272 | 2024.10.23 | N18W31 | |||||||||
| 13872 | 2024.10.23 2024.10.24 |
6 | 17 | 6 | S16E14 | 0390 | EKO | CSO |
 |
 |
area: 0180 SWPC data includes trailing spot of AR 13873 |
| 13871 | 2024.10.24 | S09W23 | part of AR 13869 | ||||||||
| 13873 | 2024.10.24 2024.10.24 |
10 | 41 | 17 | S12E10 | 0100 | HRX | EKI |
 |
 |
location: S15E05 area: 0580 SWPC data does not include leader spot |
| S10276 | 2024.10.24 | S26W49 | |||||||||
| S10277 | 2024.10.24 | N11W41 |
 |
||||||||
| S10278 | 2024.10.24 | 10 | 1 | S22E08 | 0015 | BXO |
 |
 |
|||
| S10279 | 2024.10.24 | 7 | 2 | N15W09 | 0015 | BXO |
 |
 |
|||
| 13874 | 2024.10.24 2024.10.25 |
25 | 40 | 20 | N27W31 | 0190 | DAC | EAI |
 |
 |
location: N24W32 area: 0280 |
| S10282 | 2024.10.25 | N11W23 |
 |
||||||||
| 13876 | 2024.10.25 2024.10.25 |
25 | 49 | 24 | S05W18 | 0290 | DKC | DKC |
 |
 |
beta-gamma location: S05W19 area: 0500 |
| S10284 | 2024.10.25 | S15E18 | |||||||||
| 13877 | 2024.10.25 2024.10.27 |
1 | 14 | 5 | S15E23 | 0010 | AXX | CRO |
 |
 |
location: S16E24 area: 0025 |
| S10287 | 2024.10.25 | N15W49 | |||||||||
| S10288 | 2024.10.26 | S01W38 | |||||||||
| 13878 | 2024.10.26 2024.10.27 |
8 | 31 | 20 | N16E51 | 0290 | EKI | EKC |
 |
 |
beta-delta location: N15E52 area: 0550 |
| S10290 | 2024.10.26 | S21W33 |
 |
||||||||
| S10291 | 2024.10.27 | N24W30 | |||||||||
| S10292 | 2024.10.27 | 1 | N18E32 | 0001 | AXX |
 |
 |
||||
| 13879 | 2024.10.28 2024.10.29 |
1 | 2 | 1 | N14E74 | 0450 | HKX | CHO |
 |
 |
|
| S10294 | 2024.10.28 | N49W21 |
 |
||||||||
| S10295 | 2024.10.28 | N10E12 |
 |
||||||||
| S10296 | 2024.10.28 | S01E22 |
 |
||||||||
| S10297 | 2024.10.29 | 3 | 1 | S12E31 | 0008 | AXX |
 |
||||
| S10298 | 2024.10.29 | 1 | S13E81 | 0002 | AXX |
 |
|||||
| Total spot count: | 110 | 283 | 127 | ||||||||
| Sunspot number: | 220 | 453 | 267 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 173 | 346 | 190 | (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): | 242 | 249 | 214 | ||||||||
| 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 |
| 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 | 136.8 (+5.7) | 5.31 |
| 2024.03 | 154.4 | 152.9 | 103.7 | 141.3 (+4.5) | 11.03 |
| 2024.04 | 161.3 | 162.6 | 136.5 | (145.3 projected, +4.0) | 9.69 |
| 2024.05 | 187.7 | 191.9 | 171.7 | (151.6 projected, +6.3) | 23.56 (SC25 peak) |
| 2024.06 | 184.3 | 190.2 | 164.2 | (155.5 projected, +3.9) | 10.24 |
| 2024.07 | 196.6 | 203.0 | 196.5 | (158.4 projected, +2.9) | 7.13 |
| 2024.08 | 246.1 (cycle peak) |
252.2 | 215.5 (SC25 peak) | (160.4 projected, +2.0) | 15.96 |
| 2024.09 | 195.7 | 197.8 | 141.4 | (163.1 projected, +2.7) | 15.36 |
| 2024.10 | 217.7 (1) | 146.8 (2A) / 156.9 (2B) / 206.1 (2C) ISN monthly average to date: 165 |
(165.4 projected, +2.3) | (19.5) | |
| 2024.11 | (163.7 projected, -1.7) | ||||
| 2024.12 | (160.7 projected, -3.0) | ||||
| 2025.01 | (156.3 projected, -4.4) | ||||
| 2025.02 | (149.6 projected, -6.7) | ||||
| 2025.03 | (144.8 projected, -4.8) | ||||
| 2025.04 | (141.6 projected, -3.2) | ||||
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 activity in October 2024 increased over September and looks to be headed for an SSN near 160. The average solar flux for October will become the second highest for a month during SC25. The above plot now displays the peak in 365d smoothed sunspot numbers in mid October. ISN has a peak on October 15, NOAA SN on October 14 while both the 1K and 2K SDO SN peaked on October 16. Assuming that the average sunspot number from October 2024 until April 14, 2025 becomes 150, we would be looking at a 365 days smoothed sunspot maximum of 164.5 centered on October 15. Should the average sunspot number for that period become 160 we would get a peak near 169.7.
--------------------------------------------------------------------------------------
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.
