The geomagnetic field was at quiet to unsettled levels on May 14. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. The above 10 MeV proton flux was at 26 pfu at the end of the day.
Solar flux density measured at 20h UT on 2.8 GHz was 219.8 - increasing 3.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 160.01. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 160.01 on November 14, 2023). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.6). Three hour interval K indices: 12132221 (planetary), 22123322 (Boulder), 21133231 (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: 354) and in 17 active regions using 1K resolution (SN: 252) SDO/HMI images.
Region 13667 [N27W55] was quiet and stable.
Region 13670 [N14W38] decayed slowly and quietly.
Region 13671 [N19W33] developed slowly and was mostly quiet.
Region 13672 [N19W05] decayed slowly and quietly.
Region 13673 [S09E17] decayed slowly and quietly.
Region 13674 [S13E26] was mostly quiet and stable.
Region 13675 [S15W70] decayed slowly and quietly.
Region 13676 [S20W20] decayed further and was quiet.
Region 13678 [N09E39] decayed slowly and quietly.
Region 13679 [S09E48] developed slowly and could produce M flares.
Region 13680 [N17E50] decayed slowly and quietly.
Region 13681 [S10W32] decayed slowly and quietly.
New region 13682 [N13E58] rotated into view on May 12 and was
numbered by SWPC 2 days later. Further M class flaring is possible.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9689 [S11W03] was quiet and stable.
S9692 [N22W33] decayed slowly and quietly.
S9700 [S24E07] developed slowly and quietly as new flux emerged.
S9708 [N16E13] was quiet and stable.
New region S9711 [N27W04] emerged with a tiny spot.
Minor update posted at 15:05 UT: It's rare that 2 different spot groups produce X class flares the same day. AR S9676 behind the southwest limb was the source of an X3.4 flare at 08:37 UT while newly numbered AR S9714 at the southeast limb was the origin of an X2.9 flare at 14:38 UT. The latter spot group is rotating into view and produced several flares yesterday while behind the limb.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| M2.5 | 01:48 | 13671 | GOES16 | ||
| X1.7 | 02:09 | S9676 | GOES16 | moderate type II radio sweep | |
| C8.1 | 03:27 | S9676 | GOES16 | ||
| C6.5 | 04:08 | 13679 | GOES16 | ||
| C6.5 | 04:57 | S9676 | GOES16 | ||
| C6.6 | 05:09 | S9676 | GOES16 | ||
| C6.8 | 05:29 | behind southeast limb | GOES16 | ||
| C8.2 | 08:27 | S9676 | GOES16 | ||
| M1.1 | 10:08 | spotless plage northeast quadrant | GOES16 | ||
| C8.4 | 11:13 | S9676 | GOES16 | ||
| C8.1 | 11:25 | S9676 | GOES16 | ||
| C7.1 | 12:10 | S9676 | GOES16 | ||
| X1.2 | 12:55 | S9676 | GOES16 | moderate type II radio sweep | |
| C5.9 | 14:52 | S9676 | GOES16 | ||
| C9.6 | 15:28 | S9676 | GOES16 | ||
| C6.0 | 16:07 | 13679 | GOES16 | ||
| X8.7 | 16:51 | S19W90 | S9676 | GOES16 | partial halo CME, largest flare of SC25 modewrate type II and weak type IV radio sweeps |
| M4.4/2N | 17:38 | N19E72 | 13682 | GOES16 | moderate type II radio sweep, CME |
| M3.9 | 18:08 | 13682 | GOES16 | ||
| M1.2 | 20:01 | 13679 | GOES16 | ||
| C6.3 | 22:14 | behind southeast limb | GOES16 | ||
| C7.2 | 23:14 | S9676 | GOES16 | incorrectly attributed to AR 13679 by SWPC | |
| C6.3 | 23:56 | behind southeast limb | GOES16 | simultaneous flare in AR S9676 |
May 14: A partial halo CME was observed after the X8.7 flare in AR
S9676. Due to a flare in AR 13682 and a subsequent CME near the east limb a
little later, it was impossible to determine if the first CME was a full
halo CME. Any effects from the CME could reach Earth on May 17.
May 13: A full halo CME was observed after the M6.6 long duration
event peaking at 09:44 UT in AR S9676. This CME could reach Earth on May 15
and cause unsettled to major geomagnetic storming.
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.
[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 minor storm levels on May 15-17 assuming that the May 12 and 13 CMEs reach Earth. Quiet to active is likely on May 17.
| 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 | ||||||||||
| 13669 | 2024.05.02 2024.05.05 |
S09W83 |
location: S10W73 |
||||||||
| 13667 | 2024.05.03 2024.05.04 |
4 | 1 | 1 | N27W60 | 0080 | HSX | HSX |
 |
 |
area: 0110 location: N27W55 |
| 13670 | 2024.05.05 2024.05.06 |
5 | 5 | 2 | N19W37 | 0060 | DAO | BXO |
 |
 |
location: N14W38 SWPC has moved AR 13670 to the position of AR 13671 and AR 13671 to the position of AR S9692. What a mess! |
| 13671 | 2024.05.06 2024.05.09 |
6 | 17 | 10 | N23W38 | 0020 | CRO | DAI |
 |
 |
location: N19W33 SWPC location on May 10 was N19E17, then they changed that to the location of AR S9692 area: 0140 |
| S9684 | 2024.05.07 | S24W41 | |||||||||
| 13672 | 2024.05.08 2024.05.09 |
4 | 13 | 5 | N19W11 | 0060 | CSO | CAO |
 |
 |
location: N19W05 area: 0080 SWPC location is way off |
| S9689 | 2024.05.08 | 5 | S11W03 | 0012 | AXX |
 |
 |
||||
| 13675 | 2024.05.09 2024.05.11 |
8 | 7 | 3 | S15W71 | 0030 | DRO | DRO |
 |
 |
location: S15W70 |
| 13673 | 2024.05.09 2024.05.11 |
1 | 4 | 3 | S09E13 | 0010 | HRX | CSO |
 |
 |
area: 0040 location: S09E17 |
| S9692 | 2024.05.09 | 13 | 8 | N22W33 | 0040 | DRI |
 |
 |
|||
| S9694 | 2024.05.09 | S04W26 | |||||||||
| 13676 | 2024.05.10 2024.05.12 |
9 | 13 | 5 | S22W19 | 0120 | DSI | DSC |
 |
 |
location: S20W20 area: 0160 |
| 13674 | 2024.05.10 | 11 | 27 | 16 | S12E25 | 0140 | CSO | DAO |
 |
 |
area: 0170 location: S13E26 |
| S9700 | 2024.05.11 | 15 | 6 | S24E07 | 0050 | DRI |
 |
 |
|||
| 13678 | 2024.05.11 2024.05.12 |
3 | 2 | 1 | N09E37 | 0010 | AXX | BXO |
 |
 |
location: N09E39 |
| 13681 | 2024.05.11 2024.05.13 |
1 | 1 | S07W35 | 0005 | AXX |
 |
 |
|||
| 13677 | 2024.05.11 2024.05.12 |
S02W67 |
 |
location: S02W64 | |||||||
| S9704 | 2024.05.11 | N10W27 | |||||||||
| S9705 | 2024.05.11 | S24E01 |
 |
||||||||
| 13679 | 2024.05.12 | 6 | 15 | 6 | S09E46 | 0230 | DSO | EKI |
 |
 |
beta-gamma location: S09E48 area: 0390 |
| 13680 | 2024.05.12 2024.05.13 |
3 | 9 | 3 | N18E51 | 0010 | DAO | CRO |
 |
 |
area: 0030 location: N17E50 |
| 13682 | 2024.05.12 2024.05.14 |
5 | 16 | 8 | N15E59 | 0130 | DAO | CAO |
 |
 |
location: N13E58 |
| S9708 | 2024.05.12 | 10 | 3 | N16E13 | 0025 | BXO |
 |
 |
|||
| S9710 | 2024.05.13 | N05W25 |
 |
||||||||
| S9711 | 2024.05.14 | 1 | 1 | N27W04 | 0003 | AXX |
 |
||||
| Total spot count: | 65 | 174 | 82 | ||||||||
| Sunspot number: | 185 | 354 | 252 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 114 | 231 | 139 | (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): | 204 | 195 | 202 | ||||||||
| 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 | 193.3 (1) | 68.5 (2A) / 151.7 (2B) / 207.5 (2C) | (118.3 projected, +1.2) | (42.1) | |
| 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.
