The geomagnetic field was at quiet to active levels on October 30 due to a high speed coronal hole stream. Solar wind speed at SOHO ranged between 472 and 628 km/sec, averaging 540 km/sec (+37 compared to the previous day). The high latitude magnetometer at Andenes recorded quiet to major storm levels. The above 10 MeV proton flux was at 31 pfu at the end of the day. A slow increase was observed after 22:00 UT when 24.4 pfu was recorded, maybe due to the M7 flare in AR 13878 earlier in the evening.
Solar flux density measured at 20h UT on 2.8 GHz was 269.8 - decreasing 42.1 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 182.80. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 182.80 on May 1, 2024). The Potsdam WDC planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 14.4). Three hour interval K indices: 43343221 (planetary), 32233422 (Boulder), 63343332 (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 18 active regions using 2K resolution (SN: 480) and in 17 active regions using 1K resolution (SN: 335) SDO/HMI images.
AR 13868 [S11W45] was quiet and stable.
AR 13869 [S18W22] decayed significantly losing all penumbra on the
leader spots. The leader spot of AR 13872 continues to move closer to the
trailing spots of this region, and there's a possibility that the two spot
groups will merge.
AR 13872 [S18W17] was mostly quiet and stable.
AR 13873 [S16W09] decayed slowly and quietly.
AR 13874 [N24W44] decayed slowly and was mostly quiet.
AR 13875 [N28W28] decayed gaining many spots as new flux emerged.
AR 13876 [S04W33] gained spots as new flux emerged to the south. The
new spots may be a separate spot group. Otherwise slow decay was observed
AR 13877 [S16E09] was quiet and stable.
AR 13878 [N16E39] developed slowly and still has a magnetic delta configuration in the
largest penumbra. Another major flare is possible.
AR 13879 [N14E62] was quiet and stable.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S10278 [S22W07] decayed slowly and quietly.
S10279 [N15W20] was quiet and stable.
S10292 [N16E19] was quiet and stable.
S10295 [N11W02] reemerged with tiny spots.
S10298 [S13E68] gained spots and was quiet.
New region S10299 [S12E26] emerged with tiny spots.
New region S10300 [S09E73] rotated into view with a small spot.
New region S10301 [S08E53] emerged with a tiny spot.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C3.2 | 00:48 | 13872 | GOES16 | ||
| C3.7 | 01:54 | southwest limb | 13863 | GOES16 | |
| C3.5 | 04:16 | 13878 | GOES16 | ||
| C3.0 | 05:33 | 13878 | GOES16 | ||
| C4.1 | 06:21 | 13878 | GOES16 | ||
| C3.6 | 07:49 | 13878 | GOES16 | ||
| C3.8 | 08:11 | 13878 | GOES16 | ||
| C7.1 | 10:17 | 13876 | GOES16 | ||
| C4.6 | 12:04 | 13876 | GOES16 | ||
| C3.8 | 13:40 | 13875 | GOES16 | ||
| C3.8 | 14:29 | 13876 | GOES16 | ||
| C5.0 | 15:50 | 13878 | GOES16 | ||
| C3.6 | 16:16 | 13876 | GOES16 | simultaneous flares in ARs 13878 and 13879 | |
| C3.5 | 16:32 | 13876 | GOES18 | ||
| C3.3 | 17:34 | 13878 | GOES18 | simultaneous flare in AR S10300 | |
| C3.9 | 18:18 | 13878 | GOES16 | ||
| C3.9 | 18:41 | 13872 | GOES16 | ||
| C5.0 | 18:55 | S09W29 | 13876 | GOES16 | |
| C3.9 | 19:52 | 13876 | GOES16 | simultaneous flare in AR 13878 | |
| C4.3 | 20:03 | 13876 | GOES16 | simultaneous flare in AR 13878 | |
| C5.4 | 20:22 | 13878 | GOES16 | ||
| M7.2 | 20:52 | 13878 | GOES16 | ||
| C7.7 | 23:16 | 13878 | GOES16 | ||
| C8.3 | 23:48 | 13878 | GOES16 |
October 28, 30: 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 | ||||||||||
| 13865 | 2024.10.19 2024.10.20 |
S22W72 | |||||||||
| 13866 | 2024.10.20 2024.10.21 |
S12W64 |
 |
||||||||
| 13868 | 2024.10.21 2024.10.21 |
1 | 5 | 1 | S11W46 | 0150 | HSX | HAX |
 |
 |
area: 0230 location: S11W45 |
| 13869 | 2024.10.22 2024.10.23 |
19 | 42 | 22 | S16W26 | 0290 | EKC | CAI |
 |
 |
location: S18W22 |
| 13875 | 2024.10.23 2024.10.24 |
13 | 27 | 16 | N28W29 | 0030 | CRI | DRI |
 |
 |
beta-gamma location: N28W28 area: 0140 |
| S10272 | 2024.10.23 | N18W44 | |||||||||
| 13872 | 2024.10.23 2024.10.24 |
4 | 13 | 6 | S16W12 | 0320 | DKO | CSO |
 |
 |
area: 0210 SWPC data includes leader spot of AR 13873 |
| 13871 | 2024.10.24 | S09W37 | part of AR 13869 | ||||||||
| 13873 | 2024.10.24 2024.10.24 |
9 | 37 | 24 | S11W04 | 0040 | HAX | DKO |
 |
 |
location: S16W09 area: 0430 SWPC data does not include leader spot |
| S10277 | 2024.10.24 | N11W54 | |||||||||
| S10278 | 2024.10.24 | 3 | 1 | S22W07 | 0010 | BXO |
 |
 |
|||
| S10279 | 2024.10.24 | 12 | 3 | N15W20 | 0025 | BXO |
 |
 |
|||
| 13874 | 2024.10.24 2024.10.25 |
12 | 32 | 20 | N25W46 | 0140 | EAI | EAI |
 |
 |
location: N24W44 area: 0280 |
| S10282 | 2024.10.25 | N11W36 | |||||||||
| 13876 | 2024.10.25 2024.10.25 |
25 | 49 | 33 | S05W33 | 0340 | EKC | DAC |
 |
 |
beta-gamma location: S04W33 area: 0400 |
| S10284 | 2024.10.25 | S15E05 | |||||||||
| 13877 | 2024.10.25 2024.10.27 |
1 | 10 | 4 | S16E09 | 0010 | AXX | CRO |
 |
 |
area: 0025 |
| S10288 | 2024.10.26 | S01W51 | |||||||||
| 13878 | 2024.10.26 2024.10.27 |
15 | 46 | 25 | N16E37 | 0350 | EKI | EKC |
 |
 |
beta-delta location: N16E39 area: 0520 |
| S10290 | 2024.10.26 | S21W46 | |||||||||
| S10291 | 2024.10.27 | N24W43 | |||||||||
| S10292 | 2024.10.27 | 2 | 2 | N16E19 | 0015 | BXO |
 |
 |
|||
| 13879 | 2024.10.28 2024.10.29 |
1 | 4 | 2 | N15E60 | 0450 | HHX | CKO |
 |
 |
location: N14E62 area: 0870 |
| S10294 | 2024.10.28 | N49W34 | |||||||||
| S10295 | 2024.10.28 | 3 | N11W02 | 0006 | AXX |
 |
|||||
| S10296 | 2024.10.28 | S01E09 | |||||||||
| S10297 | 2024.10.29 | S12E18 |
 |
||||||||
| S10298 | 2024.10.29 | 7 | 3 | S13E68 | 0030 | CRO |
 |
 |
|||
| S10299 | 2024.10.30 | 6 | 1 | S12E26 | 0010 | BXO |
 |
||||
| S10300 | 2024.10.30 | 1 | 1 | S09E73 | 0010 | HRX |
 |
||||
| S10301 | 2024.10.30 | 1 | 1 | S08E53 | 0003 | AXX |
 |
||||
| Total spot count: | 100 | 300 | 165 | ||||||||
| Sunspot number: | 200 | 480 | 335 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 168 | 367 | 232 | (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): | 220 | 264 | 268 | ||||||||
| 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 | 219.4 (1) | 153.2 (2A) / 158.3 (2B) / 205.0 (2C) ISN monthly average to date: 167 |
(165.4 projected, +2.3) | (19.4) | |
| 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.
