The geomagnetic field was at quiet to unsettled levels on August 2. The high latitude magnetometer at Andenes recorded quiet to active 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 247.1 - increasing 81.5 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 165.38. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 165.38 on February 2, 2024). The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 8.0). Three hour interval K indices: 33212213 (planetary), ******** (Boulder), 23324323 (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 15 active regions using 2K resolution (SN: 408) and in 15 active regions using 1K resolution (SN: 285) SDO/HMI images.
AR 13763 [N05W75] was quiet and stable.
AR 13764 [S02W70] decayed slowly and quietly.
AR 13765 [S10W58] produced several C and M flares. AR 13767 was
merged into 13765 as the two regions have no separation. Total area and
number of spots decreased signficantly.
AR 13766 [S06W70] decayed slowly and was mostly quiet.
AR 13769 [N22W14] was quiet and stable.
AR 13770 [N08W42] decayed slowly and was mostly quiet. The spot group
has one magnetic
delta configuration and there's a chance of a minor M class flare.
AR 13772 [S24E20] matured and has a magnetic delta configuration in a
small central penumbra. Further M class flares are likely.
AR 13774 [S07E42] was less active than during the previous days and
decayed significantly in the trailing spot section. A
major flare is still possible.
AR 13775 [N18E37] developed slowly and has a magnetic delta
configuration. A minor M class event is possible.
AR 13776 [N09E22] decayed slowly and quietly.
New AR 13777 [S08E61] rotated into view on August 1 and developed
slowly the next day as it was numbered by SWPC.
New AR 13778 [S19W48] emerged on July 31 and was numbered by SWPC 2
days later as the region began to decay.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9983 [S19W02] was quiet and stable.
New region S9984 [S13E43] emerged with tiny spots just south of AR
13774.
New region S9985 [N22E44] emerged with tiny spots.
C2+ flares
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C6.3 | 00:38 | 13772 | GOES16 | ||
| C6.0 | 00:46 | 13768 | GOES16 | ||
| C6.7 | 00:59 | 13768 | GOES16 | simultaneous flares in ARs 13772 and 13775 | |
| C6.5 | 01:27 | 13772 | GOES16 | ||
| M1.0 | 02:01 | 13765 | GOES16 | simultaneous flare in AR 13768 | |
| C6.0 | 02:26 | 13772 | GOES16 | ||
| C5.6 | 02:34 | 13768 | GOES16 | ||
| C9.1 | 02:50 | 13774 | GOES16 | simultaneous flare in AR 13768 | |
| M1.0 | 03:22 | 13768 | GOES16 | ||
| M1.1 | 03:25 | 13772 | GOES16 | ||
| C7.4 | 03:46 | 13773 | GOES16 | ||
| M1.1 | 03:58 | 13768 | GOES16 | ||
| C7.3 | 04:21 | 13768 | GOES16 | SWPC attributes this to smaller, simultaneous flare in AR 13765 | |
| M7.4 | 04:54 | 13768 | GOES16 | moderate type II and weak type IV radio sweeps, CME | |
| M5.5 | 05:25 | 13773 | GOES16 | ||
| M3.1 | 05:50 | 13768 | GOES16 | ||
| M1.6 | 06:59 | 13765? | GOES16 | ||
| M1.6 | 07:11 | 13774 | GOES16 | ||
| M1.5 | 07:28 | GOES16 | |||
| M2.1 | 07:59 | 13765 | GOES16 | ||
| M1.1 | 08:11 | 13772 | GOES16 | ||
| M1.3 | 08:21 | 13773 | GOES16 | ||
| M1.2 | 09:16 | S26E32 | 13772 | GOES16 | |
| M1.0 | 09:32 | 13765 | GOES16 | ||
| C8.8 | 09:41 | 13774 | GOES16 | ||
| M1.6 | 09:51 | S06W57 | 13766 | GOES16 | |
| C7.5 | 10:43 | 13777 | GOES16 | ||
| C8.9 | 10:51 | 13773 | GOES16 | simultaneous flare in AR 13765 | |
| C8.9 | 11:10 | 13774 | GOES16 | SWPC incorrectly attributes this to AR 13765 | |
| C9.2 | 11:17 | 13765 | GOES16 | ||
| C5.9 | 12:06 | 13766 | GOES16 | ||
| M1.2 | 12:33 | S08W79 | 13773 | GOES16 | |
| C9.9 | 13:01 | S22E29 | 13772 | GOES16 | simultaneous flare in AR 13765 |
| M1.1 | 13:50 | N19E43 | 13775 | GOES16 | |
| C7.6 | 15:10 | 13768 | GOES16 | ||
| M1.5 | 15:30 | S06W60 | 13766 | GOES16 | |
| C8.6 | 16:21 | S25E25 | 13772 | GOES16 | |
| C6.1 | 17:13 | 13768 | GOES16 | ||
| C6.1 | 17:40 | 13765 | GOES16 | ||
| C7.5 | 18:13 | 13774 | GOES16 | ||
| C8.2 | 18:19 | 13774 | GOES16 | SWPC attributes this to AR 13765 | |
| C6.7 | 18:55 | 13768 | GOES16 | ||
| C5.5 | 20:38 | 13766 | GOES16 | ||
| C6.5 | 21:28 | 13774 | GOES16 | ||
| C5.3 | 22:12 | 13766 | GOES16 | simultaneous flare in AR 13765 | |
| C4.9 | 23:24 | 13774 | GOES16 | ||
| M1.3 | 23:57 | behind northeast limb | GOES16 |
August 1: An asymmetrical full halo CME was observed after an M8.2
flare in AR 13768 at 07:09 UT. Components of this CME could reach
Earth on August 4.
July 31+August 2: No obviously Earth directed CMEs were 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 trans equatorial coronal hole (CH1233) rotated across the central meridian on July 30-31, however, CH1233 was in decay most of July 30 and no significant disturbance is expected.
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 unsettled levels on August 3 with a chance of active intervals should effects from CH1233 reach Earth. Quiet to minor storm levels are possible on August 4-5 due to effects from the August 1 CME.
| 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 | ||||||||||
| 13763 | 2024.07.21 2024.07.22 |
1 | 1 | 1 | N05W79 | 0060 | HSX | HSX |
 |
 |
location: N05W75 area: 0190 |
| 13764 | 2024.07.22 2024.07.22 |
3 | 1 | 1 | S03W77 | 0070 | CSO | HAX |
 |
 |
area: 0090 location: S02W70 SWPC position is way off |
| 13765 | 2024.07.23 2024.07.23 |
28 | 40 | 19 | S11W61 | 0450 | EKC | EAC |
 |
 |
beta-gamma-delta location: S10W58 area: 0350 merged with AR 13767 |
| 13766 | 2024.07.24 | 16 | 23 | 11 | S07W70 | 0140 | EAI | ESI |
 |
 |
area: 0300 location: S06W70 |
| 13767 | 2024.07.25 | 15 | S09W52 | 0130 | DAI |
 |
merged into AR 13765 |
||||
| 13769 | 2024.07.25 2024.07.26 |
1 | 7 | 1 | N22W18 | 0080 | HSX | CSO |
 |
 |
location: N22W14 area: 0210 |
| 13770 | 2024.07.27 2024.07.28 |
10 | 15 | 9 | N07W60 | 0270 | DHO | DKC |
 |
 |
beta-delta location: N07W56 area: 0320 |
| S9966 | 2024.07.28 | N30W32 | |||||||||
| 13772 | 2024.07.29 2024.07.30 |
12 | 53 | 29 | S25E20 | 0350 | EKC | EHC |
 |
 |
beta-gamma-delta area: 0720 location: S23E33 |
| S9968 | 2024.07.29 | N34W22 | |||||||||
| S9969 | 2024.07.29 | N08W08 |
 |
||||||||
| S9970 | 2024.07.29 | N11W41 | |||||||||
| S9972 | 2024.07.29 | N24W36 | |||||||||
| S9973 | 2024.07.29 | S12W37 | |||||||||
| 13775 | 2024.07.30 2024.07.31 |
6 | 30 | 20 | N17E32 | 0040 | DAC | DAC |
 |
 |
beta-delta location: N18E37 area: 0250 SWPC area and position appears not to have been measured |
| 13773 | 2024.07.30 2024.07.30 |
S06W88 |
 |
location: S07W84 |
|||||||
| 13774 | 2024.07.30 | 2 | 52 | 26 | S06E40 | 0250 | EKI | EHC |
 |
 |
beta-gamma-delta location: S07E42 area: 0770 SWPC forgot to update spot count and area for the second consecutive day |
| S9977 | 2024.07.30 | N05W20 | |||||||||
| S9978 | 2024.07.30 | N31W47 | |||||||||
| 13776 | 2024.07.31 2024.08.01 |
4 | 4 | 3 | N10E20 | 0030 | CRO | CRO |
 |
 |
area: 0020 location: N09E22 |
| 13778 | 2024.07.31 2024.08.02 |
3 | 5 | 2 | S18W49 | 0010 | BXO | BXO |
 |
 |
location: S19W48 |
| 13777 | 2024.08.01 2024.08.02 |
1 | 14 | 7 | S09E61 | 0010 | AXX | DAO |
 |
 |
location: S08E61 area: 0070 |
| S9983 | 2024.08.01 | 4 | 1 | S19W02 | 0008 | BXO |
 |
 |
|||
| S9984 | 2024.08.02 | 5 | 4 | S13E43 | 0015 | CRO |
 |
||||
| S9985 | 2024.08.02 | 2 | 1 | N22E44 | 0004 | AXX |
 |
||||
| Total spot count: | 102 | 256 | 135 | ||||||||
| Sunspot number: | 232 | 406 | 285 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 175 | 327 | 206 | (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): | 255 | 223 | 228 | ||||||||
| 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 |
| 2022.11 | 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 | 131.1 (+1.7) | 5.46 |
| 2024.02 | 172.5 | 168.3 | 123.0 | (134.7 projected, +3.6) | 5.31 |
| 2024.03 | 154.4 | 152.9 | 103.7 | (138.1 projected, +3.4) | 11.03 |
| 2024.04 | 161.3 | 162.6 | 136.5 | (141.7 projected, +3.6) | 9.69 |
| 2024.05 | 187.7 (cycle peak) |
191.9 | 171.7 | (146.2 projected, +4.5) | 23.56 (SC25 peak) |
| 2024.06 | 184.3 | 190.2 | 164.2 | (149.9 projected, +3.7) | 10.24 |
| 2024.07 | 196.9 | 203.0 | 196.5 (SC25 peak) | (151.4 projected, +1.5) | 7.1 |
| 2024.08 | 240.8 (1) | 15.9 (2A) / 246 (2B) / 224.1 (2C) | (151.3 projected, -0.1) | (13.1) | |
| 2024.09 | (151.2 projected, -0.1) | ||||
| 2024.10 | (151.1 projected, -0.1) | ||||
| 2024.11 | (149.1 projected, -2.0) | ||||
| 2024.12 | (144.8 projected, -4.3) | ||||
| 2025.01 | (138.6 projected, -6.2) | ||||
| 2025.02 | (133.7 projected, -4.9) | ||||
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 July 2024 were the highest we've seen during solar cycle 25. With three consecutive months of high sunspot counts the projected peak for the smoothed ISN (365 days smoothing) has increased significantly to near 150. The month of the peak is currently likely to occur sometime between June and October 2024.
--------------------------------------------------------------------------------------
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.
