Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 27, 2025 at 04:00 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 (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 active levels on November 26 under the influence of effects associated with CH1332. Solar wind speed at SOHO ranged between 640 and 807 km/sec, averaging 743 km/sec (-12km/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 120.8 - increasing 0.5 over the previous solar rotation.

The 365 day average solar flux at 1 AU was 157.92 (183 days ago). The 81 day average solar flux at 1 AU was 141.5 (41 days ago, this is 45.8% 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 23 (STAR Ap - based on the average of three hour interval ap indices: 22.6). Three hour interval K indices: 34444433 (planetary), 34434433 (Boulder), 54545565 (Andenes).

The background x-ray flux is at the class B5 level (GOES 19).

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 186) and in 8 active regions using 1K resolution (SN: 124) SDO/HMI images.

AR 14286 [S16W46] decayed slowly and produced several low level C flares. Note that this is AR 14292 to SWPC. C1 flares: C1.1 @ 05:56, C1.2 @ 06:11, C1.2 @ 06:45, C1.1 @ 20:10, C1.0 @ 21:24 UT
AR 14287 [N01W26] decayed slowly and quietly.
AR 14288 [N17W04] decayed slowly and quietly.
AR 14290 [S09E07] decayed slowly and was mostly quiet.
AR 14291 [S13E12] still has a magnetic delta configuration in the central spot section and could produce a minor M class flare. C1 flares: C1.0 @ 05:21, C1.9 @ 10:24, C1.1 @ 13:33, C1.3 @ 17:15, C1.3 @ 21:35 UT
AR 14293 [N08E18] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
AR S11616 [S22W47] reemerged with a tiny spot.
AR S11634 [S17W13] reemerged with a tiny spot.
AR S11638 [N25W09] was quiet and stable.
New AR S11640 [S13E52] emerged with tiny spots.

A C1.1 flare was recorded at 22:57 UT with an origin behind the southeast limb.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.2 03:00 S13E17 14290 GOES18  

Coronal mass ejections (CMEs)

November 24-26: No obviously Earth directed CMEs were observed in available coronagraph imagery.
November 25: Many CMEs were observed from an 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 active levels on November 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
  18 8 S15W61 0100   DAI

was AR S11613

location: S16W46

S11616 2025.11.16   1 1 S22W47 0003   AXX    
14287 2025.11.18
2025.11.19
1 1 1 N01W27 0020 HRX HAX was AR S11622

area: 0030

location: N01W26

14289 2025.11.19
2025.11.21
      S02W19         was AR S11623

location: S03W16

14288 2025.11.20
2025.11.20
4 16 6 N17W05 0140 CSO CSO

was AR S11626

area: 0200

location: N17W04

14290 2025.11.20
2025.11.21
1 9 3 S10E04 0070 HSX CAO

was AR S11627

area: 0130

location: S09E07

S11628 2025.11.20       N11W50            
S11629 2025.11.21       N22W57            
14291 2025.11.21
2025.11.22
18 31 23 S14E12 0200 EAI DSC beta-delta

was AR S11630

area: 0360

location: S13E12

S11632 2025.11.21       N09W38            
14293 2025.11.22
2025.11.24
  4   N08E16 0005   BXO was AR S11633

location: N08E18

14292 2025.11.23 11     S16W47 0090 DAI       ref. AR 14286
S11634 2025.11.23   1   S17W13 0002   AXX    
S11635 2025.11.24       N16W33            
S11636 2025.11.24       N09W35          
S11638 2025.11.25   3 1 N25W09 0006   BXO  
S11640 2025.11.26   2 1 S13E52 0004   BXO    
Total spot count: 35 86 44  
Sunspot number: 85 186 124  (total spot count + 10 * number of spotted regions)
Weighted SN: 58 111 69  (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): 94 102 99  

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
2025.11 139.1 (1)   77.1 (2A) / 89.0 (2B) / 112.9 (2C)
ISN average to date: 95
At this level the May 2025 SSN
will become 128.7
(106.8 projected, -2.3) (21.6)
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.