The geomagnetic field was at quiet to severe storm levels on May 12. A solar wind shock was observed at ACE at 08:57 UT, likely the arrival of the May 10 CME. The high latitude magnetometer at Andenes recorded unsettled to very severe storm levels. The above 10 MeV proton flux was at 2.5 pfu at the end of the day.
Solar flux density measured at 20h UT on 2.8 GHz was 221.8 - increasing 29.9 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 159.56. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 159.56 on November 12, 2023). The Potsdam WDC planetary A index was 56 (STAR Ap - based on the mean of three hour interval ap indices: 55.9). Three hour interval K indices: 67442346 (planetary), 58542236 (Boulder), 87443477 (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: 410) and in 18 active regions using 1K resolution (SN: 312) SDO/HMI images.
Region 13664 [S17W84] was quiet and
stable.
Region 13667 [N27W30] decayed slowly and quietly.
Region 13670 [N17W08] decayed slowly and quietly.
Region 13671 [N20E05] was mostly quiet and stable.
Region 13672 [N19E20] decayed slowly and quietly.
Region 13673 [S09E42] was quiet and stable.
Region 13674 [S14E51] was mostly quiet and stable.
Region 13675 [S15W42] has minor polarity intermixing and produced a
few flares.
New region 13676 [S21E09] emerged on May 10 and was numbered by SWPC
2 days later as development persisted. The region has a magnetic delta
configuration in the central parts and further M class flares are possible.
New region 13677 [S03W38] emerged on May 11 with SWPC numbering the
region the following day.
New region 13678 [N09E67] rotated into view on May 11 and received
its NOAA number the next day.
New region 13679 [S08E75] rotated into view and may be capable of
producing further M class flares.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9676 [S19W73] decayed slowly and is still a huge, very complex spot
group. The largest magnetic delta configuration consists of a large area of
positive polarity flux sandwiched between negative polarity areas. Another X
class flare is possible while the region rotates over the southwest limb.
S9692 [N23W09] was mostly quiet and stable.
S9702 [S08W05] developed slowly and quietly.
New region S9706 [N18E78] rotated into view with a few small spots.
New region S9707 [N13E84] rotated partly into view.
New region S9708 [N12E28] was observed with tiny spots in an old
plage area.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C6.4 | 00:28 | S9689 | GOES16 | ||
| M3.2 | 00:45 | S20W68 | S9676 | GOES16 | |
| C4.8 | 01:08 | S9676 | GOES16 | ||
| C7.1 | 01:55 | S9676 | GOES16 | ||
| C6.5 | 02:16 | S9676 | GOES16 | ||
| C6.8 | 02:26 | S9700 | GOES16 | ||
| C8.8 | 03:06 | S9676 | GOES16 | ||
| C6.4 | 03:48 | S9676 | GOES16 | ||
| C5.8 | 04:04 | S9676 | GOES16 | ||
| C4.6 | 04:32 | 13675 | GOES16 | ||
| C5.0 | 04:45 | S9676 | GOES16 | ||
| C5.5 | 05:27 | S9676 | GOES16 | ||
| M2.4 | 05:52 | northeast limb | S9707 | GOES16 | |
| M1.0 | 06:26 | S9676 | GOES16 | ||
| C6.3 | 07:01 | 13676 | GOES16 | ||
| C5.0 | 07:59 | S9676 | GOES16 | simultaneous flare at the northeast limb | |
| C8.3 | 08:40 | S9676 | GOES16 | ||
| C6.2 | 09:04 | 13675 | GOES16 | ||
| C7.9 | 09:38 | S9676 | GOES16 | ||
| C9.2 | 10:22 | S18W67 | S9676 | GOES16 | |
| C7.9 | 10:41 | S9676 | GOES16 | ||
| C7.0 | 10:57 | S9676 | GOES16 | ||
| C7.0 | 11:34 | 13675 | GOES16 | ||
| M1.6 | 12:41 | S9676 | GOES16 | ||
| M1.2 | 12:51 | S9676 | GOES16 | ||
| M1.0 | 13:47 | S09E78 | 13679 | GOES16 | |
| M1.5 | 13:56 | S21W70 | S9676 | GOES16 | simultaneous flare in AR 13675 |
| M1.2 | 14:21 | S9676 | GOES16 | ||
| C9.1 | 14:36 | S9676 | GOES16 | ||
| C7.4 | 14:44 | S9676 | GOES16 | ||
| C5.0 | 15:08 | 13675 | GOES16 | ||
| C7.0 | 15:26 | S20W75 | S9676 | GOES16 | |
| C7.4 | 15:31 | S9676 | GOES16 | ||
| C7.3 | 15:44 | northeast limb | unassigned | GOES16 | |
| C6.3 | 16:06 | 13675 | GOES16 | ||
| X1.0/1F | 16:26 | S18W72 | S9676 | GOES16 | |
| M1.0 | 17:10 | 13675 | GOES16 | ||
| M1.1 | 17:21 | 13675 | GOES16 | ||
| C8.5 | 17:42 | S9676 | GOES16 | ||
| C7.5 | 18:02 | S9676 | GOES16 | simultaneous flare in AR 13675 | |
| C7.6 | 18:11 | S9676 | GOES16 | ||
| C5.5 | 19:32 | S9676 | GOES16 | ||
| C7.2 | 19:47 | S9676 | GOES16 | ||
| C6.8 | 19:57 | S9676 | GOES16 | ||
| M4.8 | 20:32 | S18W74 | S9676 | GOES16 | |
| M1.2 | 21:10 | S9676 | GOES16 | ||
| M1.1 | 22:06 | S16W80 | S9676 | GOES16 | |
| M1.1 | 22:18 | S9676 | GOES16 | incorrectly attributed to AR 13676 by SWPC | |
| C6.7 | 23:06 | S9676 | GOES16 | ||
| M1.0 | 23:10 | S17W77 | S9676 | GOES16 | |
| C9.5 | 23:39 | 13676 | GOES16 | incorrectly attributed to AR 13664 (S9676) by SWPC |
May 12: Several CMEs were observed during the first half of the day.
While none of them are obviously earthbound, there's a chance of a weak CME
impact on May 15.
May 11: The X5 flare in AR
S9676 at 01:23 UT was associated with a bright halo CME.
May 10: The X3 flare in AR
S9676 at 06:54 UT was associated with another halo CME.
[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. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be at quiet to major storm levels on May 13-14 due to CMEs from flare activity in AR S9676. Quiet to active conditions are likely on May 15.
| 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 | ||||||||||
| 13664 | 2024.04.30 2024.05.01 |
28 | 1 | 1 | S19W75 | 1920 | FKC | HSX |
 |
 |
area: 0140 location: S17W83 SWPC includes AR S9676 in this spot group |
| 13665 | 2024.05.01 2024.05.02 |
S05W75 |
location: S06W54 SWPC location is way off |
||||||||
| 13669 | 2024.05.02 2024.05.05 |
S09W55 |
location: S10W47 |
||||||||
| 13668 | 2024.05.03 2024.05.05 |
S15W69 | merged with AR S9676 on May 9 | ||||||||
| 13667 | 2024.05.03 2024.05.04 |
2 | 7 | 5 | N27W32 | 0090 | HAX | HAX |
 |
 |
area: 0160 location: N27W30 |
| S9676 | 2024.05.05 | 40 | 24 | S19W73 | 1850 | FKC |
 |
 |
beta-gamma-delta | ||
| 13670 | 2024.05.05 2024.05.06 |
2 | 13 | 6 | N19W09 | 0020 | CSO | BXO |
 |
 |
location: N17W08 SWPC has moved AR 13670 to the position of AR 13671 and AR 13671 to the position of AR S9692. What a mess! |
| S9679 | 2024.05.06 | N15W46 | |||||||||
| 13671 | 2024.05.06 2024.05.09 |
8 | 16 | 8 | N24W10 | 0030 | DRO | DRI |
 |
 |
location: N20W09 SWPC location on May 10 was N19E17, then changed that to the location of AR S9692 |
| S9682 | 2024.05.07 | N15W56 | |||||||||
| S9683 | 2024.05.07 | S26W47 | |||||||||
| S9684 | 2024.05.07 | S24W15 | |||||||||
| 13672 | 2024.05.08 2024.05.09 |
4 | 14 | 5 | N18E17 | 0080 | CSO | DAO |
 |
 |
location: N19E20 area: 0120 |
| S9687 | 2024.05.08 | S07W37 | |||||||||
| S9689 | 2024.05.08 | S10E33 |
 |
||||||||
| 13675 | 2024.05.09 2024.05.11 |
5 | 24 | 16 | S14W43 | 0060 | DSI | DAI |
 |
 |
area: 0250 location: S15W42 |
| 13673 | 2024.05.09 2024.05.11 |
1 | 1 | 1 | S10E41 | 0030 | HSX | HSX |
 |
 |
area: 0050 location: S09E42 |
| S9692 | 2024.05.09 | 27 | 15 | N23W09 | 0070 | DRI |
 |
 |
|||
| S9693 | 2024.05.09 | N13W45 | |||||||||
| S9694 | 2024.05.09 | S04W00 | |||||||||
| S9696 | 2024.05.09 | S30W49 | |||||||||
| 13676 | 2024.05.10 2024.05.12 |
10 | 33 | 21 | S22E09 | 0130 | DAI | DSC |
 |
 |
beta-delta location: S21E09 area: 0200 |
| 13674 | 2024.05.10 | 3 | 18 | 10 | S14E53 | 0110 | CSO | CAO |
 |
 |
area: 0170 location: S14E51 |
| S9700 | 2024.05.11 | S20E37 |
|
||||||||
| 13678 | 2024.05.11 2024.05.12 |
1 | 2 | 2 | N08E65 | 0010 | HSX | CAO |
 |
 |
location: N08E67 area: 0030 |
| S9702 | 2024.05.11 | 18 | 9 | S08W05 | 0040 | DRI |
 |
|
|||
| 13677 | 2024.05.11 2024.05.12 |
1 | 4 | 2 | S02W38 | 0010 | AXX | CRO |
 |
 |
location: S03W38 |
| S9704 | 2024.05.11 | N10W01 |
 |
||||||||
| S9705 | 2024.05.11 | S23E28 |
 |
||||||||
| 13679 | 2024.05.12 | 1 | 5 | 3 | S09E73 | 0020 | HSX | DAO |
 |
location: S08E75 area: 0100 |
|
| S9706 | 2024.05.12 | 3 | 2 | N18E78 | 0050 | HAX |
 |
||||
| S9707 | 2024.05.12 | 1 | 1 | N13E84 | 0100 | HSX |
 |
||||
| S9708 | 2024.05.12 | 3 | 1 | N12E28 | 0007 | AXX |
 |
||||
| Total spot count: | 66 | 230 | 132 | ||||||||
| Sunspot number: | 186 | 410 | 312 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 124 | 307 | 209 | (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): | 205 | 226 | 250 | ||||||||
| 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 (current SC25 peak) |
| 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) (SC25 solar max candidate) |
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 | (125.2 projected, +0.4) | 12.20 |
| 2023.12 | 151.1 | 146.4 | 114.2 | (121.9 projected, -3.3) | 9.60 |
| 2024.01 | 164.6 | 159.3 | 123.0 | (118.5 projected, -3.4) | 5.46 |
| 2024.02 | 172.5 | 168.3 | 124.7 | (117.7 projected, -0.8) | 5.31 |
| 2024.03 | 154.4 | 152.9 | 104.9 | (117.1 projected, -0.6) | 11.03 |
| 2024.04 | 161.3 | 162.6 | 136.5 | (117.1 projected, -0.0) | 9.69 |
| 2024.05 | 189.3 (1) | 55.9 (2A) / 144.3 (2B) / 202.7 (2C) | (118.3 projected, +1.2) | (46.2) | |
| 2024.06 | (117.4 projected, -0.9) | ||||
| 2024.07 | (115.7 projected, -1.7) | ||||
| 2024.08 | (113.8 projected, -1.9) | ||||
| 2024.09 | (112.5 projected, -1.3) | ||||
| 2024.10 | (111.1 projected, -1.4) | ||||
| 2024.11 | (108.6 projected, -2.5) | ||||
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
The big increase in sunspot counts during the April 14-27 interval caused a major uptick in the smoothed SNs and solar flux. It's not yet clear when the next peak will be, anytime between October 28 and December 20, 2023 looks possible. The 365d smoothed solar flux exceeded the June 27 peak on October 28, while the 365d smoothed ISN and NOAA SN both exceeded the June 2023 peak in late October 2023. It should be noted that the current peak using 13-month smoothing is still in June 2023.
--------------------------------------------------------------------------------------
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.
