The geomagnetic field was at quiet to unsettled levels on July 15. The high latitude magnetometer at Andenes recorded quiet to major storm levels. The above 10 MeV proton flux was at background levels at the end of the day. A transient (CME) was observed reaching ACE+DSCOVR near 21:35 UT and caused a disturbance late in the day and early on July 16.
Solar flux density measured at 20h UT on 2.8 GHz was 233.2 - increasing 40.5 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 163.76. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 163.76 on January 15, 2024). The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 5.3). Three hour interval K indices: 11111113 (planetary), ******** (Boulder), 11112126 (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 23 active regions using 2K resolution (SN: 576) and in 20 active regions using 1K resolution (SN: 370) SDO/HMI images.
AR 13738 [S08W70] lost
spots and continued to produce C and M flares.
AR 13742 [S25W06] decayed slowly and quietly.
AR 13743 [S09W15] developed further and has minor polarity
intermixing.
AR 13744 [N16W02] decayed slightly and could still produce a minor M
class flare.
AR 13745 [S19W09] developed slowly and was mostly quiet.
AR 13748 [N15E15] was quiet and stable.
AR 13749 [S33E42] was quiet and stable.
AR 13750 [S20E41] developed slowly and quietly.
AR 13751 [S08E51] developed further becoming a compact region with a
weak magnetic delta configuration. M flares are possible.
AR 13752 [N23E57] developed slowly and quietly.
New AR 13753 [N11W22] developed further and was quiet.
New AR 13754 [N25E70] rotated into view on July 14 and was numbered
the next day by SWPC.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9884 [N15W49] reemerged with tiny spots.
S9885 [S07W50] reemerged with a tiny spot.
S9895 [S08W09] developed slowly and quietly.
New region S9907 [N22E68] was split off from AR 13754.
New region S9908 [N02E75] rotated into view.
New region S9909 [S17E80] rotated into view with a mature spot.
New region S9910 [S29E02] emerged with a tiny spot.
New region S9911 [N18E87] began to rotate into view late in
the day.
New region S9912 [N29W33] was observed with tiny spots in an old
plage area.
New region S9913 [S21E16] was observed with tiny spots in an
old plage area.
New region S9914 [S06E29] emerged with a tiny spot.
C2+ flares
Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
C3.8 | 00:25 | 13738 | GOES16 | ||
C3.1 | 01:23 | 13751 | GOES16 | ||
C3.1 | 01:29 | 13738 | GOES16 | ||
C3.3 | 02:06 | 13738 | GOES16 | ||
C3.8 | 02:21 | 13738 | GOES16 | ||
C3.2 | 02:34 | 13738 | GOES16 | ||
C3.3 | 03:08 | 13738 | GOES16 | ||
C3.8 | 03:12 | 13751 | GOES16 | ||
M1.2 | 03:45 | S11W57 | 13738 | GOES16 | |
C4.2 | 04:20 | 13738 | GOES16 | ||
C3.6 | 04:48 | 13744 | GOES16 | ||
C7.1 | 05:12 | 13744 | GOES16 | ||
C3.2 | 07:40 | 13744 | GOES16 | ||
C2.9 | 08:09 | 13744 | GOES16 | ||
C4.3 | 08:29 | 13738 | GOES16 | ||
C3.8 | 08:41 | 13738 | GOES16 | ||
C3.7 | 09:19 | 13738 | GOES16 | ||
M2.7 | 09:37 | 13738 | GOES16 | ||
M1.9 | 10:13 | 13738 | GOES16 | simultaneous flare in AR 13754 | |
M1.1 | 10:39 | 13754 | GOES16 | simultaneous flare in AR 13738 | |
C4.8 | 12:54 | 13751 | GOES16 | simultaneous flare in AR 13738 | |
C4.6 | 13:22 | 13744 | GOES16 | ||
C4.9 | 13:42 | 13738 | GOES16 | ||
C5.1 | 15:21 | 13743 | GOES16 | ||
C4.5 | 16:17 | 13738 | GOES16 | ||
C3.2 | 17:24 | 13751 | GOES16 | ||
C3.7 | 18:11 | 13742 | GOES16 | ||
C4.2 | 18:32 | 13750 | GOES16 | ||
C5.0 | 18:56 | 13751 | GOES16 | simultaneous flare in AR 13738 | |
C7.9 | 20:08 | 13751 | GOES16 | ||
C8.2 | 21:25 | 13742/13745 | GOES16 | ||
C9.8 | 21:37 | 13750 | GOES16 | ||
C7.5 | 22:15 | 13738 | GOES16 | ||
C9.4 | 22:33 | 13751 | GOES16 | simultaneous flare in AR 13738 | |
C7.3 | 22:48 | 13750 | GOES16 | ||
C6.4 | 23:21 | 13751 | GOES16 |
July 13-15: No obviously Earth directed CMEs 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]
A large recurrent negative polarity coronal hole (CH1232) in the northern hemisphere will be rotating across the central meridian on July 14-16.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is fair. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be quiet to unsettled on July 16-18 with a chance of active intervals on July 17-18 due to possible effects from CH1232.
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 | ||||||||||
13738 | 2024.07.04 2024.07.05 |
19 | 33 | 16 | S09W68 | 1010 | FKC | FKC |
beta-gamma-delta location: S08W70 |
||
13741 | 2024.07.07 2024.07.07 |
N09W51 | location: N10W43 | ||||||||
13742 | 2024.07.07 2024.07.09 |
14 | 8 | S21W25 | 0190 | HSX |
location: S25W06 SWPC split off the trailing spot section into AR 13747 on 2024.07.11 |
||||
13743 | 2024.07.08 2024.07.09 |
15 | 58 | 35 | S08W17 | 0140 | DAI | EAI |
beta-gamma area: 0210 location: S09W15 |
||
13745 | 2024.07.08 2024.07.10 |
3 | 26 | 10 | S18W11 | 0020 | CSO | DRO |
area: 0060 location: S19W09 |
||
13744 | 2024.07.09 2024.07.09 |
7 | 33 | 12 | N16W01 | 0120 | CSO | DAI |
beta-gamma area: 0160 location: N16W02 |
||
S9884 | 2024.07.09 | 3 | 3 | N15W49 | 0012 | HRX | |||||
S9885 | 2024.07.09 | 1 | 1 | S08W50 | 0003 | AXX | |||||
S9886 | 2024.07.09 | S24W54 | |||||||||
13753 | 2024.07.10 2024.07.15 |
7 | 35 | 16 | N12W22 | 0050 | DAO | DAI |
location: N11W22 area: 0240 |
||
13746 | 2024.07.10 2024.07.11 |
N23W78 |
location: N21W75 |
||||||||
13748 | 2024.07.10 2024.07.12 |
4 | 19 | 10 | N14E14 | 0010 | BXO | DRI |
area: 0050 location: N15E15 |
||
S9893 | 2024.07.10 | N40W33 | |||||||||
13747 | 2024.07.11 | 2 | S25W07 | 0130 | HSX | AR 13747 is the trailing polarity section of AR 13742 | |||||
S9895 | 2024.07.12 | 22 | 12 | S08W09 | 0070 | DRI | |||||
13750 | 2024.07.12 2024.07.13 |
9 | 31 | 13 | S20E38 | 0090 | CAO | DAI |
beta-gamma location: S20E41 area: 0200 |
||
13749 | 2024.07.12 2024.07.13 |
4 | 8 | 3 | S32E36 | 0040 | CAO | EAO |
area: 0070 location: S33E42 |
||
13751 | 2024.07.13 2024.07.13 |
10 | 33 | 15 | S08E54 | 0220 | DSI | EAC |
beta-gamma-delta location: S08E52 area: 0550 |
||
13752 | 2024.07.13 2024.07.14 |
1 | 5 | 4 | N22E53 | 0030 | HSX | DSO |
area: 0070 location: N23E57 |
||
S9901 | 2024.07.13 | N35W04 | |||||||||
S9902 | 2024.07.13 | N25W25 | |||||||||
13754 | 2024.07.14 | 4 | 5 | 4 | N23E69 | 0030 | DRO | DAO |
southernmost spots split off into AR S9907 location: N25E70 area: 0100 |
||
S9904 | 2024.07.14 | N16E37 | |||||||||
S9905 | 2024.07.14 | S35E24 | |||||||||
S9906 | 2024.07.14 | S24W35 | |||||||||
S9907 | 2024.07.15 | 3 | 1 | N22E68 | 0010 | CRO | |||||
S9908 | 2024.07.15 | 7 | 3 | N02E75 | 0060 | DAO | |||||
S9909 | 2024.07.15 | 1 | 1 | S17E80 | 0150 | HSX | |||||
S9910 | 2024.07.15 | 1 | 1 | S29E02 | 0003 | AXX | |||||
S9911 | 2024.07.15 | 1 | N18E87 | 0050 | HSX | ||||||
S9912 | 2024.07.15 | 2 | N29W33 | 0003 | AXX | ||||||
S9913 | 2024.07.15 | 4 | 2 | S21E16 | 0008 | AXX | |||||
S9914 | 2024.07.15 | 1 | S06E29 | 0001 | AXX | ||||||
Total spot count: | 85 | 346 | 170 | ||||||||
Sunspot number: | 205 | 576 | 370 | (total spot count + 10 * number of spotted regions) | |||||||
Weighted SN: | 143 | 427 | 246 | (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): | 226 | 317 | 296 |
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 |
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 | (128.9 projected, -0.5) | 5.46 |
2024.02 | 172.5 | 168.3 | 123.0 | (129.4 projected, +0.5) | 5.31 |
2024.03 | 154.4 | 152.9 | 103.7 | (130.3 projected, +0.9) | 11.03 |
2024.04 | 161.3 | 162.6 | 136.5 | (131.0 projected, +0.7) | 9.69 |
2024.05 | 187.7 (cycle peak) |
191.9 | 171.7 (SC25 peak) | (133.2 projected, +2.2) | 23.56 (SC25 peak) |
2024.06 | 184.3 | 190.2 | 164.2 | (134.9 projected, +1.7) | 10.24 |
2024.07 | 190.5 (1) | 77.7 (2A) / 160.7 (2B) / 180.2 (2C) | (134.7 projected, -0.2) | (5.4) | |
2024.08 | (134.1 projected, -0.6) | ||||
2024.09 | (134.4 projected, +0.1) | ||||
2024.10 | (134.3 projected, -0.1) | ||||
2024.11 | (132.3 projected, -2.0) | ||||
2024.12 | (128.0 projected, -4.3) | ||||
2025.01 | (124.0 projected, -4.0) |
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 June 2024 were almost at the level of May 2024 and the second highest month during solar cycle 25. Looking at the projected activity for the remainder of this year, solar max now looks likely to occur between May and October 2024. A big decrease in sunspot formation in July 2024 and over the next months could change the projected maximum to earlier in 2024 or even to December 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.