Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 10, 2025 at 05:00 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data since 2003.01 (July 1, 2025)
Solar cycle Solar cycles 23-25 (July 1, 2025) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (July 1, 2025) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (August 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (July 1, 2025) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (July 1, 2025) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (April 21, 2025) Cycle 25 spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing  

Recent activity

The geomagnetic field was at quiet to unsettled levels on July 9 under the decreasing influence of effects associated with CH1305. Solar wind speed at SOHO ranged between 401 and 514 km/sec, averaging 455 km/sec (-85 km/sec compared to the previous day). The high latitude magnetometer at Andenes recorded quiet to minor storm levels. The above 10 MeV proton flux was at background levels all day.

Solar flux density measured at 20h UT on 2.8 GHz was 120.2 - decreasing 21.3 over the previous solar rotation. The 365 day average solar flux at 1 AU was 184.15 (183 days ago). The 81 day average solar flux at 1 AU was 138.8 (41 days ago, this is 44.1% of the SC25 solar flux range from the max 81 day average peak on September 4, 2024 at 227.3 and an average 81 day flux of 69 at solar minimum). SC25 365d peak: 195.86 on October 13, 2024. 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: 32112211 (planetary), 33232212 (Boulder), 53122324 (Andenes).

The background x-ray flux is at the class B9 level (GOES 19).

At the time of counting spots (see image time), spots were observed in 13 active regions using 2K resolution (SN: 209) and in 12 active regions using 1K resolution (SN: 160) SDO/HMI images.

AR 14125 [N22W84] was quiet and stable.
AR 14130 [S09W51] decayed slowly and quietly.
AR 14132 [S15W46] gained a few spots and was quiet.
AR 14134 [S21W59] decayed slowly and quietly.
AR 14135 [S08E42] decayed slowly and was mostly quiet. C1 flares: C1.3 @ 22:05 UT
New AR 14136 [N19E67] rotated into view on July 8 and was numbered by SWPC the next day. The region could produce further M class flares. C1 flares: C1.3 @ 12:02, C1.4 @ 12:52, C1.8 @ 15:08, C1.7 @ 15:57, C1.2 @ 18:38 UT
New AR 14137 [N18W21] emerged on July 8 and developed further on July 9 when it was numbered by SWPC.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
S11218 [N05W40] was quiet and stable.
S11230 [S18W20] reemerged with tiny spots.
New AR S11236 [N10E45] was observed with tiny spots in an old plage area.
New AR S11237 [S04E74] rotated into view with tiny spots.
New AR S11238 [N13W12] was observed with tiny spots in an old plage area.
New AR S11239 [S03E04] emerged with tiny spots.

A C1.7 flare was recorded at 23:01 UT (no SDO/AIA imagery to pinpoint the location). Other C1 flares without location: C1.0 @ 19:16, C1.1 @ 19:36, C1.1 @ 19:54, C1.0 @ 21:21 UT. A long duration C1.9 event peaking at 13:55 UT had its source behind the southeast limb.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.4 00:53   14136 GOES18  
M1.3 04:25   14136 GOES18  

Coronal mass ejections (CMEs)

July 7-9: No obviously Earth directed CMEs.

Coronal holes

[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 trans equatorial positive polarity coronal hole (CH1306) will be Earth facing on July 8-14.

Forecast

The geomagnetic field is expected to be mostly quiet on July 10. July 11-17 could see unsettled to minor storm levels due to effects associated with CH1306 with the strongest disturbance likely on July 11-12 and July 14-15.

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.

Active solar regions



(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
STAR SWPC STAR Current Previous
2K 1K
14125 2025.06.26
2025.06.27
1 1 1 N23W85 0020 HSX HSX was AR S11199

location: N22W84

area: 0040

14128 2025.06.27
2025.06.29
      S05W88           was AR S11202
14129 2025.06.28
2025.06.30
      N04W85        

was AR S11206

location: N03W81

14132 2025.06.29
2025.07.01
  11 6 S17W49 0025   CRO

was AR S11209

location: S15W46

14130 2025.06.30
2025.06.30
2 3 1 S09W51 0010 BXO CRO was AR S11211
S11213 2025.06.30       N10W43          
S11218 2025.07.03   8 2 N05W40 0015   BXO  
S11219 2025.07.03       S05W24            
S11221 2025.07.03       S15W28            
14134 2025.07.05
2025.07.06
2 4 2 S22W59 0010 BXO CRO was AR S11224

location: S21W59

S11225 2025.07.05       N23W44            
14135 2025.07.06
2025.07.07
5 10 3 S08E43 0070 DAO CAO was AR S11226

area: 0130

location: S08E42

S11227 2025.07.06       S26W25            
S11229 2025.07.07       S10E04            
S11230 2025.07.07   2 1 S18W20 0005   BXO    
14137 2025.07.08
2025.07.09
6 13 9 N19W22 0030 CRO DAI was AR S11231

location: N18W21

area: 0160

14136 2025.07.08
2025.07.09
7 13 10 N19E64 0150 DAI DKI was AR S11232

area:

location: N19E67

area: 0480

S11233 2025.07.08       N18E27          
S11236 2025.07.09   5 1 N10E45 0010   AXX    
S11237 2025.07.09   2   S04E74 0003   BXO    
S11238 2025.07.09   5 2 N13W12 0010   AXX    
S11239 2025.07.09   2 2 S03E04 0006   BXO    
Total spot count: 23 79 40  
Sunspot number: 83 209 160  (total spot count + 10 * number of spotted regions)
Weighted SN: 41 113 74  (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): 91 115 128  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2024.01 164.6 159.3 126.0 131.2 (+1.7) 5.46
2024.02 172.5 168.3 123.0 136.9 (+5.7) 5.31
2024.03 154.4 152.9 103.7 141.4 (+4.5) 11.03
2024.04 161.3 162.6 137.0 144.5 (+3.1) 9.69
2024.05 187.7 191.9 172.1 149.1 (+4.6) 23.56
(SC25 peak)
2024.06 184.3 190.2 164.1 152.8 (+3.7) 10.24
2024.07 196.6 203.0 196.8 155.0 (+2.3) 7.13
2024.08  246.1
(cycle peak)
252.2 216.0  (SC25 peak) 156.8 (+1.8) 15.96
2024.09 195.7 197.8 141.1 159.4 (+1.6) 15.36
2024.10 221.0 219.6 165.8 160.8 (+1.4) (SC25 solar max) 18.99
2024.11 199.6 195.3 154.1 157.0 (-3.8) 9.33
2024.12 197.3 191.2 154.6 151.2 (-5.8) 8.42
2025.01 190.3 184.2 137.0 (146.0 projected, -5.2) 13.17
2025.02  184.2 179.7 154.6 (138.2 projected, -7.8) 14.42
2025.03 163.7 162.1 134.2 (131.8 projected, -6.4) 15.96
2025.04 162.5 163.6 140.6 (127.2 projected, -4.6) 17.62
2025.05  135.3 138.3 79.2 (121.9 projected, -5.3) 17.26
2025.06 131.3 135.4 116.3 (117.0 projected, -4.9) 21.43
2025.07 121.0 (1)   30.0 (2A) / 103.2 (2B) / 132.7 (2C) (112.8 projected, -4.2) (13.3)
2025.08       (108.1 projected, -4.7)  
2025.09       (103.8 projected, -4.3)  
2025.10       (99.9 projected, -3.9)  
2025.11       (97.6 projected, -2.3)  
2025.12       (96.0 projected, -1.6)  

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 27 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

Solar cycles 24-25

Smoothed SF and sunspot numbers

Update on the progress of solar cycle 25 as of June 23, 2025

Sunspot activity has been on a decreasing trend since September 2024 (using the average solar flux over 3 solar rotations as a proxy). Compared to the peak of SC25 solar flux has been at a low level in both May and June 2025. Taking a closer look at the 81 day (3 solar rotations) average solar flux proxy, its peak was in early September 2024 and had on May 12 decreased to less than half of the solar cycle flux range. Subtracting the 81 day average of approximately 69 at solar cycle minimum from all measurements, the SC25 range is 0 - 158.3.

All 365 day smoothed sunspot numbers peaked on October 11-12, 2024
, very likely making this the peak of SC25 (365 day smoothed peaks: STAR 1K: 236.1, STAR 2K: 364.3, NOAA SN: 156.0, ISN: 163.6). The 365d smoothed solar flux peaked on October 13, 2024, just 1.7% below the SC23 peak, and 62.6% above the SC24 peak.

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This report has been prepared by Jan Alvestad. It is based on the analysis of data from whichever 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.