Solar Terrestrial Activity Report

Activity chart

Last major update issued on September 14, 2022 at 11:40 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 (September 1, 2022)
Solar cycle Solar cycles 23-25 (September 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (September 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (July 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (September 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (September 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 21, 2022) Cycle 25 spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing Research: Solar Cycle 25 Started on November 17, 2019 with 365 Days Smoothing

Recent activity

The geomagnetic field was very quiet on September 13. Solar wind speed at SOHO ranged between 303 and 377 km/sec. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. A weak (likely) solar wind shock was observed at 06:23 UT at DSCOVR on September 14.

Solar flux density measured at 20h UT on 2.8 GHz was 154.1 - increasing 31.4 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 111.42). The Potsdam WDC planetary A index was 2 (STAR Ap - based on the mean of three hour interval ap indices: 2.5). Three hour interval K indices: 01111101 (planetary), 11312311 (Boulder), 00012003 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 235) and in 9 active regions using 1K resolution (SN: 154) SDO/HMI images.

Region 13096 [N17W19] decayed slowly and quietly.
Region 13098 [N19W51] developed slowly and still has a magnetic delta in a leading polarity penumbra. M class flares are possible.
Region 13100 [S24E08] decayed slowly and quietly.
Region 13101 [N31W85] rotated mostly out of view with only the easternmost spot being visible at the end of the day.
New region 13102 [S27E61] rotated into view on September 12 and was numbered the next day by SWPC. C and M class flares are possible.

Spotted regions not observed (or interpreted differently) by SWPC:
S7842 [S24W28] was quiet and stable.
S7843 [N13W12] was quiet and stable.
S7858 [N13W49] developed slowly and quietly.
S7860 [S17E35] decayed slowly and quietly.
S7862 [S18E19] developed slowly and quietly.
New region S7867 [N31E08] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C4.3 00:45   13102 GOES16  
C3.1 01:33   13098 GOES16  
C2.4 02:21   13098 GOES16  
C2.6 03:06   13098 GOES16 simultaneous flare in AR 13102
C4.4 03:52   13102 GOES16  
C2.9 04:19   13101 GOES16  
C3.9 05:59   13101 GOES16 incorrectly attributed to AR 13094 by SWPC
C2.6 06:41   13101 GOES16  
C3.0 07:27   13098 GOES16  
C3.7 08:58   13101 GOES16  
C4.1 10:09   13098 GOES16  
C3.2 10:23   13098 GOES16  
C2.6 10:50   13101 GOES16  
C4.0 11:30 S30E76 13102 GOES16 simultaneous flare in AR 13101
C2.9 12:00 N19W41 13098 GOES16  
C7.0 12:36 N30W82 13101 GOES16  
C3.1 13:31   13098 GOES16  
C7.0 14:08 N30W90 13101 GOES16 incorrectly attributed to AR 13102 by SWPC
C9.1 15:20 N24W48 13098 GOES16  
C9.2 15:34   13101 GOES16  
C6.9 15:50   13101 GOES16  
C4.9 17:28   13098 GOES16  
C2.5 17:55   13101 GOES16  
C2.2 20:29 N18W52 13098 GOES16  
C3.5 22:13   13098 GOES16 incorrectly attributed to AR 13102 by SWPC
C4.1 22:34 N18W53 13098 GOES16  
C3.4 22:50   13098 GOES16 simultaneous flare in AR 13101
C3.2 23:55   13098 GOES16  

Coronal mass ejections (CMEs)

September 11-13: No obviously Earth directed CMEs were observed.

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 northern hemisphere coronal hole (CH1099) will rotate across the central meridian on September 13-14.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is poor. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to unsettled conditions are expected on September 14-15 due to effects from CH1098. Quiet to active conditions are likely on September 16-17 when a high speed stream from CH1099 could reach Earth.

Coronal holes (1) Coronal mass ejection (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
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13092 2022.08.31
2022.09.01
1     S10W94 0030 HSX    

rotated out of view

13094 2022.09.02
2022.09.02
      N20W69           location: N19W66
13097 2022.09.05
2022.09.07
1     S11W85 0000 AXX    

location: S12W82

spotless

13096 2022.09.05
2022.09.06
2 6 2 N18W19 0000 AXX BXO

 

location: N17W19

area: 0008

S7842 2022.09.05   1 1 S23W28 0003   AXX  
S7843 2022.09.06   5 2 N13W12 0010   BXO  
13098 2022.09.06
2022.09.08
18 50 28 N18W51 0460 EHC EKC beta-gamma-delta

area: 0640

location: N19W51

S7845 2022.09.06       S09W34            
13100 2022.09.08
2022.09.10
7 28 17 S24E22 0140 CSO EAI

location: S24E08

13099 2022.09.09
2022.09.10
      N12W10          
S7853 2022.09.09       S04W35            
S7854 2022.09.09       S16W25            
13101 2022.09.10
2022.09.10
  1 1 N29W85 0100   HAX

 

S7857 2022.09.10       N24W45          
S7858 2022.09.10   7 4 N13W49 0050   CAO  
S7860 2022.09.10   5   S17E35 0008   BXO  
S7861 2022.09.10       S02W06            
S7862 2022.09.11   11 4 S18E19 0020   BXO  
S7863 2022.09.11       S21W00            
S7864 2022.09.11       S21W49            
13102 2022.09.12
2022.09.13
4 10 5 S28E60 0330 CSO EKO location: S27E61
S7866 2022.09.12       N11W48          
S7867 2022.09.13   1   N31E08 0002   AXX    
Total spot count: 33 125 64  
Sunspot number: 93 235 154  (total spot count + 10 * number of spotted regions)
Weighted SN: 58 160 99  (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): 102 129 123  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (SC24 peak) 110.5 10.70
2014.04 143.9 144.8 112.5 116.4 (solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(cycle peak)
2019.11 70.2 68.7 0.5 2.0 (-0.6)
(Solar minimum using 365d smoothing:
November 17, 2019)
4.19
2019.12 70.8 68.6 1.6 1.8 (-0.2)
(ISN 13 months smoothed
solar minimum)
3.22
2021.02 74.3 72.4 8.2 19.0 (+1.7) 9.50
2021.03 76.0 75.2 17.2 21.7 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.8 (+3.1) 8.40
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
2021.06 79.4 81.8 25.0 27.6 (+1.8) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.8) 5.51
2021.08 77.7 79.7 22.0 35.4 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.2 (+4.8) 6.33
2021.10 88.9 88.3 37.4 45.2 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.8 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.9 (+5.1) 6.40
2022.01 103.8 100.5 55.3 60.1 (+4.2) 8.92
2022.02 109.1 106.5 60.9 64.8 (+4.7) 10.46
2022.03 117.0 115.8 78.6 (68.7 projected, +3.9) 10.20
2022.04 130.8 131.7 84.1 (73.9 projected, +5.2) 11.79
2022.05 133.8 136.8 96.5 (80.3 projected, +6.4) 7.48
2022.06 116.1 119.8 70.5 (86.2 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (93.4 projected, +7.2) 9.51
2022.08 114.2 117.1 75.4 (100.0 projected, +6.6) 10.92
2022.09 132.7 (1)   35.6 (2A) / 82.5 (2B) / 107.5 (2C) (104.9 projected, +4.9) (17.8)
2022.10       (108.1 projected, +3.2)  
2022.11       (110.9 projected, +2.8)  
2022.12       (115.7 projected, +4.8)  
2023.01       (121.7 projected, +6.0)  
2023.02       (126.7 projected, +5.0)  
2023.11       (142.5 projected max SC25)  

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 30 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: SIDC-SILSO.

Solar cycles 24-25

Smoothed SF and sunspot numbers

 

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