Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 13, 2026 at 08:25 UT. Due to Internet connectivity issues, updates will be irregular until July 17.

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, 2026)
Solar cycle Solar cycles 23-25 (July 1, 2026) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (July 1, 2026) 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, 2026) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (July 1, 2026) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (December 21, 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 quiet to active levels, under the influence of effects associated with CH1383. Solar wind speed at SOHO ranged between 450 and 603 km/sec, averaging 518 km/sec (-5 km/sec compared to the previous day). The high latitude magnetometer at Andenes was at unsettled to minor storm levels. The above 10 MeV proton flux was at background levels.

Solar flux density measured at 20h UT on 2.8 GHz was 107.3 - decreasing 5.5 over the previous solar rotation.

The 365 day average solar flux at 1 AU was 141.17 (183 days ago). The 81 day average solar flux at 1 AU was 137.6 (41 days ago, this is 43.3% 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 16 (STAR Ap - based on the average of three hour interval ap indices: 16.4). Three hour interval K indices: 32334332 (planetary), 43444423 (Boulder), 44455344 (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 7 active regions using 2K resolution (SN: 98) and in 6 active regions using 1K resolution (SN: 75) SDO/HMI images.

AR 14482 [S08W30] was mostly quiet and stable.
AR 14485 [S11W79] decayed slowly and rotated partly out of view. C1 flares: C1.3 @ 02:49, C1.0 @ 15:32, C1.0 @ 15:40, C1.1 @ 23:07 UT
AR 14487 [N09W28] decayed slowly and quietly.
AR 14488 [N22W26] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
AR S12210 [N05W29] decayed slowly and quietly.
New AR S12214 [N08E22] emerged with tiny spots.
New AR S12215 [S07E80] rotated into view with a mature spot.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C5.9 00:57 S09W70 14485 GOES18 CME, moderate type II and IV radio sweeps
C2.8 07:32   14485 GOES18  
M1.1 08:11   14485 GOES18  
C2.6 13:58   14485 GOES18  

Coronal mass ejections (CMEs)

July 11-12: No obviously Earth directed CMEs were observed in available coronagraph imagery.
July 10: A CME was observed after a C6 flare in AR 14485. While the main ejecta will not impact Earth, there is a chance of a weak solar wind shock on July 13.

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 southern hemisphere negative polarity coronal hole (CH1383) was Earth facing on July 9. A trans equatorial positive polarity coronal hole (CH1384) rotated across the central meridian on July 11. A northern hemisphere positive polarity coronal hole (CH1385) will likely become Earth facing on July 15.

Forecast

The geomagnetic field is expected to be at mostly quiet levels on July 13. Quiet to unsettled is possible on July 14-15 due to effects associated with CH1384.

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
14485 2026.07.01
2026.07.05
18 7 5 S10W82 0170 EAC DAO

was AR S12187

location: S11W79

SWPC spot count is much higher than expected

14481 2026.07.02
2026.07.03
      N14W51        

was AR S12191

14482 2026.07.04
2026.07.04
6 12 6 S09W28 0330 CHO CKO

was AR S12197

area: 0550

location: S08W30

14487 2026.07.07
2026.07.08
4 3 1 N09W28 0010 BXO AXX was AR S12205

area: 0004

S12206 2026.07.07       N08W52            
S12207 2026.07.09       N09W20            
S12210 2026.07.10   1 1 N05W29 0004   AXX  
14488 2026.07.11
2026.07.11
2 2 1 N23W25 0010 BXO AXX was AR S12211

area: 0007

location: N22W26

S12212 2026.07.11       N14W05          
S12213 2026.07.11       S05E29          
S12214 2026.07.12   2   N08E22 0003   AXX    
S12215 2026.07.12   1   S07E80 0220   HAX    
Total spot count: 30 28 14  
Sunspot number: 70 98 74  (total spot count + 10 * number of spotted regions)
Weighted SN: 45 48 34  (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): 77 54 59  

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)
2024.08  246.1
(SC25 peak)
252.2 216.0  (SC25 peak) 156.8 (+1.8) 15.96
2024.10 221.0 219.6 165.8 160.9 (+1.5) (SC25 solar max) 18.99
2025.04 162.5 163.6 141.4 133.3 (-2.6) 17.62
2025.05 135.3 138.3 78.5 128.6 (-4.7) 17.26
2025.06 131.3 135.4 114.6 124.7 (-3.9) 21.43
2025.07 137.8 142.3 125.9 122.5 (-2.2) 11.80
2025.08 154.9 158.7 133.7 118.4 (-4.1) 9.97
2025.09 154.4 156.0 129.7 113.1 (-5.3) 14.02
2025.10 139.5 138.6 114.6 108.5 (-4.6) 15.64
2025.11 140.3 137.3 91.7 106.9 (-1.6) 21.01
2025.12 160.8 155.8 124.0 107.0 (-0.1) 13.35
2026.01 148.7 144.0 115.0 (104.4 projected, -2.6) 22.47
2026.02 136.4 133.1 77.4 (100.0 projected, -4.4) 12.88
2026.03 131.0 129.7 86.6 (94.7 projected, -5.3) 15.44
2026.04  120.0 120.9 79.3 (90.8 projected, -3.9) 12.10
2026.05 125.4 128.2 101.4 (89.5 projected, -1.3) 9.80
2026.06 137.9 142.2 94.3 (87.4 projected, -2.1) 9.57
2026.07 139.8 (1)   34.8 (2A) / 89.9 (2B) / 106.9 (2C) (82.9 projected, -4.5) (15.6)
2026.08       (80.7 projected, -2.2)  
2026.09       (79.8 projected, -0.9)  
2026.10       (77.7 projected, -2.1)  
2026.11       (74.9 projected, -2.8)  
2026.12       (71.7 projected, -3.2)  

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 March 2026

Solar activity appears to have exited the solar max phase as of February 2026 with a strong decrease in the number of sunspots observed. The northern polar field has weakened considerably over the last months, and although there is a chance the the field could recover over the next 1-2 years, there is an increasing chance that solar cycle 26 will be very weak. The southern polar field is not impressive either, however, a southern polar coronal hole has formed early in 2026 and appears to be growing.

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.

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

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.