The geomagnetic field was at very quiet levels on July 13. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. The above 10 MeV proton flux was at background levels at the end of the day.
Solar flux density measured at 20h UT on 2.8 GHz was 238.7 - increasing 71.4 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 163.47. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 163.47 on January 13, 2024). The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.4). Three hour interval K indices: 11101111 (planetary), ******** (Boulder), 20102113 (Andenes).
The background x-ray flux is at the class C4 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 17 active regions using 2K resolution (SN: 487) and in 14 active regions using 1K resolution (SN: 294) SDO/HMI images.
AR 13736 [S19W68] decayed
slowly and quietly.
AR 13738 [S09W42] saw a strong increase in flare activity during the
day and early on July 14. The largest flare was an X1.2 event at 02:34 UT on
July 14 and it had its origin in the southernmost large penumbra. The spot group has
several magnetic delta
configurations and could produce further major flares. Some decay was
observed in the trailing spot section.
AR 13741 [N10W17] was quiet and stable.
AR 13742 [S24E18] produced a few M flares and
displayed no significant changes.
AR 13743 [S08E09] developed slowly and could produce an M class
flare.
AR 13744 [N16E26] developed slowly and was mostly quiet.
AR 13745 [S18E17] developed slowly and was mostly quiet. A merge
between this and AR 13742 is being considered due to no obvious separation
between the spot groups.
AR 13748 [N15E42] decayed slowly and quietly.
New AR 13749 [S32E68] rotated into view on July 12 and was numbered
by SWPC the next day.
New AR 13750 [S20E67] rotated into view on July 12 and received its
NOAA number the following day.
New AR 13751 [S08E79] rotated into view and appears to have M class
flare potential.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9884 [N18W32] was quiet and stable
S9888 [N11E07] was merged with AR S9892 and was quiet and stable.
S9895 [S08E18] was quiet and stable to the east of AR 13743.
New region S9900 [N22E80] rotated into view with a small spot.
New region S9901 [N35E27] was observed with tiny spots in an
old plage area.
New region S9902 [N25E01] was observed with tiny spots in an old
plage area.
C2+ flares
Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
C3.2 | 00:25 | 13738 | GOES16 | ||
C3.1 | 01:31 | 13738 | GOES16 | ||
C2.8 | 02:39 | 13738 | GOES16 | ||
M1.4 | 03:17 | 13738 | GOES16 | ||
C7.0 | 03:47 | 13738 | GOES16 | ||
C8.1 | 04:15 | 13751 | GOES16 | ||
C8.3 | 04:20 | 13751 | GOES16 | incorrectly attributed to AR 13738 by SWPC simultaneous flare in AR 13749 |
|
C8.0 | 04:35 | 13751 | GOES16 | incorrectly attributed to AR 13738 by SWPC | |
C9.5 | 05:10 | 13738 | GOES16 | ||
C6.1 | 05:39 | 13751 | GOES16 | ||
C4.1 | 06:17 | 13751 | GOES16 | ||
C3.4 | 07:04 | 13751 | GOES16 | simultaneous flare in AR 13743 | |
C2.9 | 07:38 | 13738 | GOES16 | ||
C2.7 | 08:13 | 13738 | GOES16 | ||
C2.8 | 09:42 | 13738 | GOES16 | ||
C2.7 | 10:29 | 13743 | GOES16 | ||
C3.5 | 12:07 | 13751 | GOES16 | incorrectly attributed to AR 13738 by SWPC | |
C4.6 | 12:19 | 13743 | GOES16 | incorrectly attributed to much smaller flare in AR 13738 by SWPC | |
M5.3/1N | 12:42 | S08W42 | 13738 | GOES16 | weak type II radio sweep |
M1.0 | 13:24 | 13742 | GOES16 | ||
C5.2 | 14:14 | 13751 | GOES16 | incorrectly attributed to AR 13738 by SWPC | |
C5.4 | 14:19 | 13738 | GOES16 | ||
C5.4 | 14:27 | 13738 | GOES16 | ||
C5.8 | 14:40 | 13738 | GOES16 | ||
C5.7 | 14:50 | 13738 | GOES16 | ||
C6.2 | 14:56 | 13738 | GOES16 | ||
M1.8 | 15:29 | 13742 | GOES16 | ||
M1.9 | 15:44 | 13738 | GOES16 | ||
C8.2 | 16:48 | 13751 | GOES16 | simultaneous flare in AR S9900 | |
C6.0 | 17:14 | 13738 | GOES16 | ||
C3.9 | 18:34 | 13738 | GOES16 | ||
C5.6 | 18:50 | 13738 | GOES16 | ||
M1.0 | 19:30 | 13738 | GOES16 | ||
C7.6 | 20:02 | 13751 | GOES16 | simultaneous flare in AR 13738 | |
C6.7 | 20:52 | S9900 | GOES16 | ||
C6.0 | 21:11 | 13738 | GOES16 | ||
C4.9 | 22:11 | 13751 | GOES16 | ||
M5.0 | 23:01 | 13738 | GOES16 |
July 11-13: 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 well defined positive polarity northern hemisphere coronal hole (CH1231) rotated across the central meridian on July 9-11.
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 14-16.
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 | ||||||||||
13736 | 2024.07.02 2024.07.03 |
1 | 2 | 1 | S20W69 | 0010 | AXX | HRX | location: S19W68 | ||
13738 | 2024.07.04 2024.07.05 |
52 | 93 | 54 | S09W40 | 1100 | FKC | FKC |
beta-gamma-delta location: S09W28 |
||
S9872 | 2024.07.06 | S07W54 | |||||||||
13741 | 2024.07.07 2024.07.07 |
3 | N09W23 | 0006 | BXO | location: N10W17 | |||||
13742 | 2024.07.07 2024.07.09 |
1 | 36 | 12 | S23E02 | 0010 | AXX | FSO |
area: 0250 location: S24E18 SWPC split off the trailing spot section into AR 13747 on 2024.07.11 |
||
S9875 | 2024.07.07 | S13W53 |
|
||||||||
13743 | 2024.07.08 2024.07.09 |
23 | 59 | 28 | S08E11 | 0220 | DAI | DAI |
beta-gamma area: 0330 location: S08E09 |
||
13745 | 2024.07.08 2024.07.10 |
3 | 23 | 12 | S15E20 | 0020 | DRO | DAO | area: 0080 | ||
13744 | 2024.07.09 2024.07.09 |
8 | 27 | 17 | N16E25 | 0160 | DSO | DAI |
beta-gamma area: 0240 location: N16E26 |
||
S9884 | 2024.07.09 | 5 | 1 | N18W32 | 0007 | AXX | |||||
S9885 | 2024.07.09 | S07W24 | |||||||||
S9886 | 2024.07.09 | S24W28 | |||||||||
S9888 | 2024.07.10 | 23 | 7 | N11E07 | 0040 | BXO | |||||
13746 | 2024.07.10 2024.07.11 |
N23W51 |
location: N21W49 |
||||||||
S9890 | 2024.07.10 | S46W33 | |||||||||
13748 | 2024.07.10 2024.07.12 |
4 | 13 | 5 | N15E43 | 0010 | BXO | DRO | |||
S9892 | 2024.07.10 | merged with AR S9888 | |||||||||
S9893 | 2024.07.10 | N40W07 | |||||||||
13747 | 2024.07.11 | 2 | S24E18 | 0180 | CSO | AR 13747 is the trailing spot section of AR 13742 | |||||
S9895 | 2024.07.12 | 6 | 3 | S08E18 | 0015 | BXO | |||||
S9896 | 2024.07.12 | N18W59 | |||||||||
13750 | 2024.07.12 2024.07.13 |
7 | 11 | 6 | S20E65 | 0110 | CSO | DAO |
location: S20E67 area: 0160 |
||
13749 | 2024.07.12 2024.07.13 |
2 | 5 | 2 | S32E66 | 0050 | CSO | DAO |
area: 0100 location: S32E68 |
||
13751 | 2024.07.13 2024.07.13 |
1 | 6 | 5 | S07E75 | 0090 | HSX | EKO |
was: AR S9899 location: S08E79 area: 0360 |
||
S9900 | 2024.07.13 | 1 | 1 | N22E80 | 0040 | HAX | |||||
S9901 | 2024.07.13 | 2 | N35E27 | 0005 | AXX | ||||||
S9902 | 2024.07.13 | 2 | N25E01 | 0005 | AXX | ||||||
Total spot count: | 104 | 317 | 154 | ||||||||
Sunspot number: | 214 | 487 | 294 | (total spot count + 10 * number of spotted regions) | |||||||
Weighted SN: | 112 | 378 | 215 | (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): | 235 | 268 | 235 |
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 | 183.9 (1) | 64.1 (2A) / 152.9 (2B) / 170.3 (2C) | (134.7 projected, -0.2) | (5.5) | |
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.