Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 15, 2025 at 06:50 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 active levels on July 14 under the influence of effects associated with CH1306. Solar wind speed at SOHO ranged between 457 and 604 km/sec, averaging 520 km/sec (-98 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 128.2 - decreasing 11.0 over the previous solar rotation. The 365 day average solar flux at 1 AU was 182.89 (183 days ago). The 81 day average solar flux at 1 AU was 136.9 (41 days ago, this is 42.9% 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 14 (STAR Ap - based on the mean of three hour interval ap indices: 13.8). Three hour interval K indices: 23313343 (planetary), 233***** (Boulder), 33214454 (Andenes).

The background x-ray flux is at the class C1 level (GOES 19).

At the time of counting spots (see image time), spots were observed in 13 active regions using 2K resolution (SN: 268) and in 11 active regions using 1K resolution (SN: 180) SDO/HMI images.

AR 14135 [S08W24] was quiet and stable.
AR 14136 [N20E04] decayed slowly and quietly.
AR 14138 [N28W55] extended further and decayed slowly.
AR 14139 [N21W16] developed slowly and was mostly quiet.
AR 14140 [S16E35] displayed decay and penumbral fragmentation. A small magnetic delta configuration is still present. C1 flares: C1.4 @ 01:44, C1.5 @ 04:49, C1.9 @ 12:24 UT
New AR 14142 [N01E47] emerged on July 13 and was numbered the next day by SWPC. The region matured and produced several C flares as there is still some polarity intermixing in the trailing spot section. C1 flares: C1.7 @ 01:01, C1.2 @ 06:48, C1.8 @ 07:58, C1.8 @ 20:21 UT
New AR 14143 [N23E15] emerged with several spots and was mostly quiet.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
S11236 [N11W24] decayed slowly and quietly.
S11251 [S09E11] was quiet and stable.
New AR S11255 [S15E75] rotated into view with a mature spot.
New AR S11256 [N06E82] rotated into view with a mature spot.
New AR S11257 [N08E17] was observed with tiny spots in an old plage area.
New AR S11258 [S25E36] emerged with tiny spots.

AR 14141 behind the southwest limb produced several C1 flares: C1.5 @ 08:55, C1.5 @ 09:07 UT

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.6 00:07   14140 GOES18  
C2.1 00:48 behind SW limb 14141 GOES18  
C2.1 02:54   14142 GOES18  
C2.6 03:23 behind SW limb 14141 GOES18  
C4.0 05:01 N01E61 14142 GOES18  
C2.3 05:41 behind SW limb 14141 GOES18  
C3.2 05:46 behind SW limb 14141 GOES18  
C2.9 09:38 behind SW limb 14141 GOES18  
C2.2 10:45 behind SW limb 14141 GOES18  
C2.0 11:05   S11250 GOES18  
C2.0 11:29   14142 GOES18  
C2.1 12:57 behind SW limb 14141 GOES18  
C2.1 13:20 behind SW limb 14141 GOES18  
C2.2 13:42   14139 GOES18  
C2.6 14:14 behind SW limb 14141 GOES18  
C3.1 14:29 behind SW limb 14141 GOES18  
C3.3 14:57 behind NW limb 14137 GOES18 simultaneous flare in AR 14141
C2.3 15:58 behind SW limb 14141 GOES18  
C4.5 17:06 behind SW limb 14141 GOES18  
C2.2 18:01   14140 GOES18  
C2.9 18:43 behind SW limb 14141 GOES18  
C2.1 19:48 behind SW limb 14141 GOES18  

Coronal mass ejections (CMEs)

July 12-14: 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 huge recurrent trans equatorial positive polarity coronal hole (CH1306) will be Earth facing on July 8-16.

Forecast

The geomagnetic field is expected to be quiet to active levels on July 15-16 due to effects from CH1306. Quiet to unsettled levels are likely on July 17-19.

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
14135 2025.07.06
2025.07.07
1 4 2 S09W24 0060 HSX CSO was AR S11226

area: 0110

location: S08W24

14137 2025.07.08
2025.07.09
3     N19W89 0040 CSO     was AR S11231

location: N18W91

rotated out of view

14136 2025.07.08
2025.07.09
7 20 12 N19W00 0150 EAO CKO beta-gamma

was AR S11232

location: N20E04

area: 0380

S11233 2025.07.08       N18W38            
S11236 2025.07.09   6   N11W24 0010   AXX  
S11237 2025.07.09       S04E12            
S11239 2025.07.09       S08W58            
14138 2025.07.10
2025.07.11
7 18 10 N28W51 0075 EAI FAI

was AR S11240

area: 0290

location: N28W55

14140 2025.07.10
2025.07.11
8 22 9 S15E32 0090 DAI DAC beta-delta

was AR S11242

location: S16E35

14139 2025.07.11
2025.07.11
13 35 21 N21W15 0070 DAO DAI

was AR S11243

area: 0300

location: N21W16

S11244 2025.07.11       N23E03            
14141 2025.07.12
2025.07.13
3     S13W90 0020 CRO     was AR S11245

rotated out of view

S11247 2025.07.12       N25E05            
S11249 2025.07.13       N30W31          
S11251 2025.07.13   3 2 S09E11 0006   BXO  
14142 2025.07.13
2025.07.14
4 9 5 N02E50 0040 CSO DAI was AR S11252

area: 0090

location: N01E47

S11253 2025.07.13       S06W37          
14143 2025.07.14
2025.07.14
3 14 5 N09E11 0010 BXO DRI   was AR S11254

area: 0040

location: N23E15

there are no spots at the location provided by SWPC, assuming that AR S11254 is the spot group in question

S11255 2025.07.14   1 1 S15E75 0060   HSX    
S11256 2025.07.14   1 1 N06E82 0050   HSX    
S11257 2025.07.14   2   N08E17 0002   AXX    
S11258 2025.07.14   3 2 S25E36 0006   BXO    
Total spot count: 49 138 70  
Sunspot number: 139 268 180  (total spot count + 10 * number of spotted regions)
Weighted SN: 87 185 117  (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): 153 147 144  

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
2024.10 221.0 219.6 165.8 160.9 (+1.5) (SC25 solar max) 18.99
2024.11 199.6 195.3 154.1 157.1 (-3.8) 9.33
2024.12 197.3 191.2 154.6 151.3 (-5.8) 8.42
2025.01 190.3 184.2 137.0 (146.1 projected, -5.2) 13.17
2025.02  184.2 179.7 155.7 (138.3 projected, -7.8) 14.42
2025.03 163.7 162.1 134.2 (131.9 projected, -6.4) 15.96
2025.04 162.5 163.6 140.6 (127.3 projected, -4.6) 17.62
2025.05  135.3 138.3 79.2 (122.0 projected, -5.3) 17.26
2025.06 131.3 135.4 116.3 (117.1 projected, -4.9) 21.43
2025.07 124.7 (1)   46.2 (2A) / 102.4 (2B) / 129.8 (2C) (112.9 projected, -4.2) (13.2)
2025.08       (108.1 projected, -4.8)  
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: 163.9). The 365d smoothed solar flux peaked on October 13, 2024, just 1.7% below the SC23 peak, and 62.6% above the SC24 peak.

--------------------------------------------------------------------------------------

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.