The geomagnetic field was very quiet on July 4. Solar wind speed at SOHO ranged between 347 and 396 km/sec. The high latitude magnetometer at Andenes recorded quiet levels.
Solar flux density measured at 20h UT on 2.8 GHz was 167.2 - unchanged over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 146.28. In comparison SC24 peaked on June 28, 2014 at 145.50). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 3.5). Three hour interval K indices: 11111111 (planetary), 11122222 (Boulder), 21111112 (Andenes).
The background x-ray flux is at the class C1 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 13 active regions using 2K resolution (SN: 315) and in 12 active regions using 1K resolution (SN: 204) SDO/HMI images.
Region 13354 [N15W79] rotated partly out of
view and produced several flares. C1 flares: C1.5 @ 11:20, C1.9 @ 16:43 UT
Region 13355 [S14W30] was quiet and stable.
Region 13356 [S08W14] decayed slowly and quietly.
Region 13357 [S06W07] decayed slowly and quietly.
Region 13358 [S13E15] decayed further and was mostly quiet.
Region 13359 [S21E14] was mostly quiet and stable. C1 flares: C1.5 @
10:54 UT
Region 13360 [N23E19] developed slowly and produced a few flares.
New region 13361 [N23E43] rotated into view on June 2 and was
numbered by SWPC 2 days later as the region developed further. Some polarity
intermixing is present and C flares are likely.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S8717 [S10E29] was quiet and stable.
S8725 [S19E30] was quiet and stable.
New region S8731 [S16W63] emerged with tiny spots.
New region S8732 [S09E76] rotated into view with a mature spot.
New region S8733 [N30E39] was observed with tiny spots in an old
plage area.
C2+ flares:
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C4.2 | 00:28 | 13360 | GOES16 | ||
| C2.5 | 01:34 | 13354 | GOES16 | ||
| C2.7 | 02:01 | 13354 | GOES16 | ||
| C2.9 | 02:27 | 13360 | GOES16 | ||
| C3.2 | 03:17 | 13360 | GOES16 | ||
| C3.8 | 04:00 | 13360 | GOES16 | ||
| C3.5 | 05:06 | 13354 | GOES16 | ||
| C7.2 | 06:41 | N24E28 | 13360 | GOES16 | simultaneous flare in AR 13354 |
| C4.1 | 07:13 | 13354 | GOES16 | ||
| C3.0 | 08:15 | S13E24 | 13358 | GOES16 | |
| C2.0 | 09:28 | 13354 | GOES16 | ||
| M1.4 | 12:35 | N16W82 | 13354 | GOES16 | |
| C6.0 | 13:29 | 13354 | GOES16 | ||
| C4.6 | 14:36 | 13354 | GOES16 | simultaneous flare in AR 13361 | |
| C2.1 | 15:17 | 13358 | GOES16 | ||
| C2.8 | 18:53 | 13354 | GOES16 | ||
| C8.0 | 19:28 | 13354 | GOES16 | ||
| C5.2 | 21:33 | 13359 | GOES16 | simultaneous flare in AR 13354 | |
| C4.8 | 22:12 | 13354 | GOES16 | simultaneous flare in AR 13359 | |
| C2.3 | 23:13 | 13354 | GOES16 | ||
| C6.0 | 23:39 | 13354 | GOES16 | attributed to flare in AR 13361 by SWPC, a flare which was smaller and peaked later |
July 2-3: No obviously Earth directed CMEs were
observed.
July 4: A filament eruption in the southeast quadrant
was observed beginning near 02:30 UT and was associated with a partial halo CME.
This CME could reach Earth on July 7.
[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 recurrent northern hemisphere coronal hole (CH1158) will be Earth facing on July 4-5.
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.
Quiet conditions are likely on July 5-6. On July 7 effects from the July 4 CME could cause unsettled to minor storm conditions. A high speed stream associated with CH1158 could cause unsettled to minor storm conditions on July 7-8.
| Coronal holes (1) | Coronal mass ejection (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 | ||||||||||
| 13354 | 2023.06.22 2023.06.26 |
25 | 10 | 6 | N16W87 | 1130 | FKC | EKC |
 |
 |
|
| 13355 | 2023.06.26 2023.06.27 |
8 | 3 | S16W32 | 0015 | CRO |
 |
 |
location: S14W30 |
||
| 13356 | 2023.06.29 2023.06.30 |
6 | 1 | S07W21 | 0010 | BXO |
 |
 |
location: S08W14 | ||
| S8711 | 2023.06.29 | N14W16 | |||||||||
| S8712 | 2023.06.29 | S12W43 | |||||||||
| S8713 | 2023.06.29 | S12W54 | |||||||||
| 13357 | 2023.06.30 2023.07.01 |
7 | 28 | 13 | S07W09 | 0040 | DAO | DRI |
 |
 |
location: S06W07 area: 0070 |
| 13358 | 2023.06.30 2023.07.01 |
13 | 29 | 15 | S14E14 | 0040 | DSI | DRI |
 |
 |
location: S13E15 area: 0060 |
| 13359 | 2023.06.30 2023.07.01 |
5 | 20 | 12 | S21E11 | 0060 | DSO | DSI |
 |
 |
location: S21E14 area: 0280 |
| S8717 | 2023.06.30 | 21 | 6 | S10E29 | 0030 | BXO |
 |
 |
|||
| S8718 | 2023.06.30 | N14W17 | |||||||||
| 13360 | 2023.06.30 2023.07.01 |
8 | 21 | 10 | N23E15 | 0030 | CAO | CAO |
 |
 |
location: N23E19 area: 0080 |
| S8720 | 2023.06.30 | N30W38 |
 |
||||||||
| S8721 | 2023.06.30 | N17W01 | |||||||||
| S8722 | 2023.07.01 | S17W55 | |||||||||
| S8724 | 2023.07.02 | N09E12 | |||||||||
| S8725 | 2023.07.02 | 11 | 4 | S19E30 | 0010 | BXO |
 |
 |
|||
| S8726 | 2023.07.02 | S37E12 | |||||||||
| S8727 | 2023.07.02 | N29W59 | |||||||||
| 13361 | 2023.07.02 2023.07.04 |
3 | 22 | 11 | N23E45 | 0010 | BXO | DAI |
 |
 |
location: N23E43 area: 0150 |
| S8729 | 2023.07.02 | N40W46 | |||||||||
| S8730 | 2023.07.03 | N18E15 |
 |
||||||||
| S8731 | 2023.07.04 | 6 | 2 | S16W63 | 0020 | CRO |
 |
||||
| S8732 | 2023.07.04 | 1 | 1 | S09E76 | 0120 | HSX |
 |
||||
| S8733 | 2023.07.04 | 2 | N30E39 | 0003 | AXX |
 |
|||||
| Total spot count: | 61 | 185 | 84 | ||||||||
| Sunspot number: | 121 | 315 | 204 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 91 | 227 | 126 | (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): | 133 | 173 | 163 | ||||||||
| 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 |
| 2021.12 | 103.0 | 99.8 | 67.5 | 55.9 (+5.1) | 6.40 |
| 2022.01 | 103.8 | 100.5 | 55.3 | 60.1 (+4.2) | 8.92 |
| 2022.02 | 109.1 | 106.5 | 60.9 | 64.7 (+4.6) | 10.46 |
| 2022.03 | 117.0 | 115.8 | 78.6 | 68.7 (+4.0) | 10.20 |
| 2022.04 | 130.8 | 131.7 | 84.0 | 73.0 (+4.3) | 11.79 |
| 2022.05 | 133.8 | 136.8 | 96.5 | 77.4 (+4.4) | 7.48 |
| 2022.06 | 116.1 | 119.8 | 70.3 | 81.1 (+3.7) | 8.20 |
| 2022.07 | 125.4 | 129.5 | 91.4 | 86.7 (+5.6) | 9.51 |
| 2022.08 | 114.2 | 117.1 | 74.6 | 92.5 (+5.8) | 10.92 |
| 2022.09 | 135.1 | 136.5 | 96.0 | 96.4 (+3.9) | 12.18 |
| 2022.10 | 133.5 | 132.7 | 95.5 | 98.7 (+2.3) | 11.16 |
| 2022.11 | 123.4 | 120.7 | 80.5 | 101.0 (+2.3) | 9.33 |
| 2022.12 | 147.9 | 143.4 | 112.8 | 106.6 (+5.6) | 10.99 |
| 2023.01 | 182.4 | 176.6 | 143.6 | (113.7 projected, +6.1) | 8.73 |
| 2023.02 | 167.2 | 163.2 | 110.9 | (118.5 projected, +4.8) | 14.48 (current SC25 peak) |
| 2023.03 | 157.2 | 155.6 | 122.6 | (121.6 projected, +3.1) | 14.42 |
| 2023.04 | 145.4 | 146.4 | 96.4 | (127.0 projected, +5.4) | 13.40 |
| 2023.05 | 155.6 | 159.2 | 137.9 | (132.7 projected, +5.7) | 10.67 |
| 2023.06 | 161.7 | 166.8 | 163.4 | (135.9 projected, +3.2) | 8.9 |
| 2023.07 | 169.0 (1) | 15.6 (2A) / 120.8 (2B) / 173.5 (2C) | (135.4 projected, -0.5) | (4.0) | |
| 2023.08 | (136.4 projected, +1.0) | ||||
| 2023.09 | (139.8 projected, +3.4) | ||||
| 2023.10 | (141.6 projected, +1.8) | ||||
| 2023.11 | (144.2 projected max SC25, +2.6) | ||||
| 2023.12 | (143.4 projected, -0.1) | ||||
| 2024.01 | (140.1 projected, -3.3) | ||||
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
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.
