Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 26, 2025 at 06:30 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 (November 1, 2025)
Solar cycle Solar cycles 23-25 (November 1, 2025) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (November 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 (November 1, 2025) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (November 1, 2025) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 17, 2025) Cycle 25 initial spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing  

Recent activity

The geomagnetic field was at unsettled to minor storm levels on November 25 under the strong influence of a high speed stream associated with CH1332. Solar wind speed at SOHO ranged between 661 and 819 km/sec, averaging 755 km/sec (+126 km/sec compared to the previous day). The high latitude magnetometer at Andenes was at active 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 116.9 - decreasing 1.5 over the previous solar rotation.

The 365 day average solar flux at 1 AU was 158.19 (183 days ago). The 81 day average solar flux at 1 AU was 141.9 (41 days ago, this is 46.1% of the total 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: 195.9 on October 13, 2024.

The Potsdam WDC planetary A index was 30 (STAR Ap - based on the average of three hour interval ap indices: 30.4). Three hour interval K indices: 55444443 (planetary), 44455432 (Boulder), 55545555 (Andenes).

The background x-ray flux is at the class B4 level (GOES 19).

At the time of counting spots (see image time), spots were observed in 9 active regions using 2K resolution (SN: 201) and in 8 active regions using 1K resolution (SN: 136) SDO/HMI images.

AR 14286 [S17W32] developed further and has polarity intermixing. A minor M flare is possible. Note that this is AR 14292 to SWPC. C1 flares: C1.3 @ 16:15, C1.1 @ 21:12 UT
AR 14287 [N01W12] decayed slowly and quietly.
AR 14288 [N17E09] decayed slowly and was mostly quiet. C1 flares: C1.6 @ 16:28 UT
AR 14289 [S03W03] decayed slowly and quietly.
AR 14290 [S10E20] decayed slowly and was mostly quiet.
AR 14291 [S13E26] regained a magnetic delta configuration in the intermediate spot section. A minor M flare is possible. C1 flares: C1.9 @ 14:34 UT
AR 14293 [N07E32] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
AR S11636 [N09W22] was quiet and stable.
New AR S11638 [N25E05] emerged with tiny spots.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.1 15:56 S16W28 14286 GOES18  

Coronal mass ejections (CMEs)

November 23-24: No obviously Earth directed CMEs were observed in available coronagraph imagery.
November 25: Many CMEs were observed from a very active region a few days behind the northeast limb. This could be the return of old AR 14274.

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 (CH1332) was Earth facing on November 22-24. A recurrent northern hemisphere negative polarity coronal hole (CH1333) began to rotate into view on November 25 and could become Earth facing on November 30 - December 1.

Forecast

The geomagnetic field is expected to be at unsettled to minor storm levels on November 26-27 due to effects associated with CH1332 and quiet to unsettled on November 28-29.

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
14286 2025.11.16
2025.11.18
  28 14 S15W47 0150   DAI beta-gamma

was AR S11613

location: S17W32

S11616 2025.11.16       S22W33            
14287 2025.11.18
2025.11.19
1 2 1 N01W14 0020 HSX HSX was AR S11622

area: 0040

location: N01W12

14289 2025.11.19
2025.11.21
1 4 2 S02W05 0010 AXX BXO was AR S11623

location: S03W03

14288 2025.11.20
2025.11.20
4 18 9 N17E08 0110 CSO CSO

was AR S11626

area: 0210

14290 2025.11.20
2025.11.21
3 9 4 S11E17 0070 CSO DSO

was AR S11627

area: 0130

location: S10E20

S11628 2025.11.20       N11W37            
S11629 2025.11.21       N22W44            
14291 2025.11.21
2025.11.22
12 35 23 S13E25 0160 EAI DAC beta-delta

was AR S11630

area: 0300

location: S13E26

S11631 2025.11.21       N12W59            
S11632 2025.11.21       N09W25            
14293 2025.11.22
2025.11.24
1 7 2 N08E30 0010 AXX BXO was AR S11633

location: N07E32

14292 2025.11.23 7     S16W34 0050 DAI       ref. AR 14286
S11634 2025.11.23       S16E01            
S11635 2025.11.24       N16W20          
S11636 2025.11.24   4 1 N09W22 0006   AXX  
S11638 2025.11.25   4   N25E05 0007   BXO    
Total spot count: 29 111 56  
Sunspot number: 99 201 136  (total spot count + 10 * number of spotted regions)
Weighted SN: 54 136 81  (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): 109 111 109  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2024.05 187.7 191.9 172.1 149.1 (+4.6) 23.56
(SC25 peak)
2024.07 196.6 203.0 196.8 155.0 (+2.3) 7.13
2024.08  246.1
(SC25 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
2024.11 199.6 195.3 154.1 157.2 (-3.7) 9.33
2024.12 197.3 191.2 154.6 151.2 (-6.0) 8.42
2025.01 190.3 184.2 137.0 146.2 (-5.0) 13.17
2025.02  184.2 179.7 155.7 139.8 (-6.4) 14.42
2025.03 163.7 162.1 134.2 135.9 (-3.9) 15.96
2025.04 162.5 163.6 141.4 133.3 (-2.6) 17.62
2025.05  135.3 138.3 78.5 (128.5 projected, -4.8) 17.26
2025.06 131.3 135.4 114.6 (123.8 projected, -4.7) 21.43
2025.07 137.8 142.3 125.6 (120.6 projected, -3.2) 11.80
2025.08 154.9 158.7 133.5 (117.0 projected, -3.6) 9.97
2025.09 154.4 156.0 129.8 (113.1 projected, -3.9) 14.02
2025.10 139.5 138.6 114.6 (109.1 projected, -4.0) 15.64
2025.11 139.8 (1)   74.3 (2A) / 89.2 (2B) / 113.6 (2C)
ISN average to date: 95
At this level the May 2025 SSN
will become 128.7
(106.8 projected, -2.3) (21.5)
2025.12       (105.3 projected, -1.5)  
2026.01       (101.2 projected, -4.1)  
2026.02       (97.1 projected, -4.1)  
2026.03       (92.8 projected, -4.3)  
2026.04       (89.0 projected, -3.8)  

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 October 2025

Sunspot activity was on a decreasing trend from September 2024 until mid August 2025 (using the average solar flux over 3 solar rotations as a proxy). Then a strong surge in activity saw solar flux peak in late August 2025 just below the largest peaks seen in 2024. A slow decrease in activity from the August level has been observed in September and October 2025.

All 365 day smoothed sunspot numbers reached a maximum on October 11-12, 2024
. This became the peak of SC25 (365 day smoothed peaks: STAR 1K: 236.1, STAR 2K: 364.3, NOAA SN: 156.0, ISN: 163.9), while 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.