Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 16, 2024 at 06:25 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 6, 2024)
Solar cycle Solar cycles 23-25 (November 1, 2024) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (November 1, 2024) 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, 2024) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (November 1, 2024) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (October 13, 2024) 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
Calculating the Strength of Solar Cycle 25 Using 365-day Smoothing

Recent activity

The geomagnetic field was at quiet to active levels on November 15. Solar wind speed at SOHO ranged between 352 and 457 km/sec, averaging 396 km/sec (+3 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 148.9 - decreasing 13.4 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 186.01. In comparison SC24 peaked on June 28, 2014 at 145.50 while SC23 peaked on February 23, 2002 at 198.15. Current SC25 peak: 186.01 on May 16, 2024). The Potsdam WDC planetary A index was 12 (STAR Ap - based on the mean of three hour interval ap indices: 11.6). Three hour interval K indices: 34323222 (planetary), 33333322 (Boulder), 35224344(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 10 active regions using 2K resolution (SN: 189) and in 8 active regions using 1K resolution (SN: 130) SDO/HMI images.

AR 13889 [S09W42] decayed slowly in the leading and intermediate spot sections. Many low level C flares were recorded. An M flare is still possible. C1 flares: C1.7 @ 00:35, C1.8 @ 08:44, C1.7 @ 15:21, C1.3 @ 16:13, C1.5 @ 16:25, C1.5 @ 17:57, C1.9 @ 20:07 UT
AR 13892 [S11W28] decayed slowly and quietly.
AR 13893 [S19E37] displayed signs of decay after the 2 M flares.
AR 13894 [N23E29] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
S10347 [S03W21] developed slowly and quietly as new flux emerged.
S10353 [N22W08] reemerged with tiny spots.
S10358 [S12W01] was quiet and stable.
New region S10360 [N14W72] emerged with a tiny spot before noon, then decayed slowly.
New region S10362 [N07W02] was observed with tiny spots in an old plage area.
New region S10363 [S38E34] emerged with tiny spots.

AR 13891 was the source of a C1.8 flare at 19:01 UT

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.2 00:59   13886 GOES16  
M1.1 01:46   13893 GOES16  
C2.2 02:39 southwest limb   GOES16  
C2.1 04:13   13889 GOES16  
C2.1 04:29   13889 GOES16  
C3.5 07:14   13889 GOES16 simultaneous flare at the southwest limb
C3.8 08:17   13889 GOES16  
C3.4 09:32   13886 GOES16  
C2.2 10:15   13889 GOES16  
C2.8 11:01 southwest limb   GOES16  
C2.9 11:16 southwest limb   GOES16  
M1.0 12:18 S20E43 13893 GOES16  
C2.5 12:57   13889 GOES16  
C2.1 15:35   13886 GOES16  
C2.7 17:06   13889 GOES16 simultaneous flare in AR 13886
C2.2 18:42   13889 GOES16  
C2.1 22:34   13889 GOES16  
C2.0 23:48   13889 GOES16  

Coronal mass ejections (CMEs)

November 13-14: No obviously Earth directed CMEs were observed.
November 15: A filament eruption in the southeast quadrant early in the day was associated with a partial halo CME. Components of this CME coud reach Earth on November 18.

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 positive polarity northern hemisphere coronal hole (CH1255) was Earth facing on November 14-15. A negative polarity southern hemisphere coronal hole (CH1256) will likely rotate across the central meridian on November 18-21.

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

The geomagnetic field is expected to be at quiet to unsettled levels on November 16 and then quiet to active on Nov. 17-18 due to effects from CH1255. Components of the November 15 CME could reach Earth on November 18 and cause unsettled and active intervals.

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
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13890 2024.11.04
2024.11.09
      S12W82           location: S13W78
13891 2024.11.05
2024.11.11
      S15W56          

location: S16W51

13889 2024.11.06
2024.11.07
20 38 28 S09W43 0540 FKI FKI beta-gamma-delta

area: 0850

location: S09W42

13892 2024.11.08
2024.11.11
2 10 3 S11W29 0010 BXO BXO

location: S11W28

S10343 2024.11.10       N17W48            
S10344 2024.11.10       S05W37            
S10347 2024.11.11   4 3 S03W21 0020   CRO  
13893 2024.11.12
2024.11.13
4 14 6 S19E34 0050 CSO CAO beta-gamma

area: 0090

location: S19E37

S10349 2024.11.12       N12W55          
S10350 2024.11.12       S27W52            
13894 2024.11.13
2024.11.14
5 11 5 N24E30 0030 CRO CRO area: 0025

location: N23E29

S10352 2024.11.13       N04E25            
S10353 2024.11.13   1   N22W08 0003   AXX    
S10355 2024.11.14       N10E08          
S10356 2024.11.14       N03E26          
S10357 2024.11.14       S17E44          
S10358 2024.11.14   6 2 S12W01 0010   BXO  
S10359 2024.11.14       S13E16          
S10360 2024.11.15   1   N14W72 0001   AXX    
S10362 2024.11.15   2 2 N07W02 0010   AXX    
S10363 2024.11.15   2 1 S38E34 0006   AXX    
Total spot count: 31 89 50  
Sunspot number: 71 189 130  (total spot count + 10 * number of spotted regions)
Weighted SN: 49 110 71  (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): 78 104 104  

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 (SC24 solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(SC24 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
2023.01 182.4 176.6 144.4 113.3 (+6.6) 8.73
2023.02 167.2 163.2 111.3 117.8 (+3.5) 14.48
2023.03 157.2 155.6 123.3 121.1 (+3.3) 14.42
2023.04 145.4 146.4 97.6 122.9 (+1.8) 13.40
2023.05 155.6 159.2 137.4 124.2 (+1.3) 10.67
2023.06 161.7 166.8 160.5 125.3 (+1.1) 8.95
2023.07  176.4 182.2 160.0 124.6 (-0.7) 8.15
2023.08  153.7 157.6 114.8 124.3 (-0.3) 7.19
2023.09  154.4 156.0 134.2 124.0 (-0.3) 14.26
2023.10  142.8 141.9 99.4 124.8 (+0.8) 8.16
2023.11 153.5 150.2 105.4 127.9 (+3.1) 12.20
2023.12 151.1 146.4 114.2 129.5 (+1.6) 9.60
2024.01 164.6 159.3 126.0 131.1 (+1.6) 5.46
2024.02 172.5 168.3 123.0 136.9 (+5.8) 5.31
2024.03 154.4 152.9 103.7 141.4 (+4.5) 11.03
2024.04 161.3 162.6 137.0 144.4 (+3.1) 9.69
2024.05 187.7 191.9 172.1 (149.7 projected, +5.3) 23.56
(SC25 peak)
2024.06 184.3 190.2 164.1 (153.6 projected, +3.9) 10.24
2024.07 196.6 203.0 196.5  (156.5 projected, +2.9) 7.13
2024.08  246.1
(cycle peak)
252.2 215.5  (SC25 peak) (158.5 projected, +2.0) 15.96
2024.09 195.7 197.8 141.4 (161.2 projected, +2.7) 15.36
2024.10 221.0 219.6 166.3 (163.5 projected, +2.3) 18.99
2024.11 210.5 (1)   76.8 (2A) / 153.6 (2B) / 207.1 (2C) (161.8 projected, -1.7) (11.8)
2024.12       (158.7 projected, -3.1)  
2025.01       (154.4 projected, -4.3)  
2025.02       (147.6 projected, -6.8)  
2025.03       (142.8 projected, -4.8)  
2025.04       (139.8 projected, -3.0)  

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: 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 27, 2024

Sunspot activity in October 2024 increased over September and looks to be headed for an SSN near 160. The average solar flux for October will become the second highest for a month during SC25. The above plot now displays the peak in 365d smoothed sunspot numbers in mid October 2024. ISN has a peak on October 15, NOAA SN on October 14 while both the 1K and 2K SDO SN peaked on October 16. Assuming that the average sunspot number from October 2024 until April 14, 2025 becomes 150, we would be looking at a 365 days smoothed sunspot maximum of 164.5 centered on October 15. Should the average sunspot number for that period become 160 we would get a peak near 169.7.

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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.