Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 27, 2022 at 05:55 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 (July 6, 2022)
Solar cycle Solar cycles 23-25 (July 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (July 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 (July 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (July 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (April 10, 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 quiet to unsettled on July 26. Solar wind speed at SOHO ranged between 368 and 560 km/sec. The high latitude magnetometer at Andenes recorded quiet to major storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 98.8 - increasing 2.6 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 106.53). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.8). Three hour interval K indices: 32122112 (planetary), 32112312 (Boulder), 65122214 (Andenes).

The background x-ray flux is at the class B2 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 7 active regions using 2K resolution (SN: 104) and in 7 active regions using 1K resolution (SN: 94) SDO/HMI images.

Region 13059 [S08W81] decayed slowly and quietly.
Region 13062 [S25W13] decayed slowly and quietly.
Region 13064 [N10W47] decayed slowly losing the leader spots and retaining only tiny spots.
Region 13065 [S19W52] decayed slowly and quietly.
Region 13066 [S15E01] decayed slowly and quietly.
New region 13067 [N19E67] rotated into view on July 25 and decayed slowly on July 26 when the group was numbered by SWPC.

Spotted regions not observed (or interpreted differently) by SWPC:
S7722 [S22W35] was quiet and stable.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C8.5 15:35 northwest limb 13060 GOES16  

Coronal mass ejections (CMEs)

July 24-26: No obviously Earth directed CMEs were observed in available LASCO imagery.

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 small northern hemisphere coronal hole (CH1090) will be Earth facing on July 26-27.

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 possible on July 27. A high speed stream from CH1090 could cause quiet to active conditions on July 28-29.

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 midnigh4t Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlays
Comment
SWPC/
USAF
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13059 2022.07.14
2022.07.15
1 1 1 S07W82 0060 HSX HSX

location: S08W81

13060 2022.07.14
2022.07.16
      N12W89          
13063 2022.07.18
2022.07.20
      N10W61         location N11W71

SWPC location is way off

S7712 2022.07.18       N28W44          
13062 2022.07.19
2022.07.19
2 3 3 S26W16 0100 CSO CSO

area: 0120

location: S25W13

13064 2022.07.19
2022.07.20
2 2 1 N09W55 0000 BXO AXX

area: 0005

location: N10W47

S7718 2022.07.20       S15W35            
13065 2022.07.21
2022.07.21
6 11 6 S20W51 0030 CRO CRO area: 0025

location: S19W52

S7722 2022.07.22   2 1 S22W35 0006   BXO  
S7723 2022.07.23       S10W21            
S7724 2022.07.23       N18W10            
13066 2022.07.24
2022.07.25
4 12 9 S16E01 0030 CRO CRI location: S15E01
S7727 2022.07.24       S17W23            
S7728 2022.07.25       N24E38          
13067 2022.07.25
2022.07.26
3 3 3 N20E65 0070 CAO CRO  
S7730 2022.07.25       N28E29          
Total spot count: 18 34 24  
Sunspot number: 78 104 94  (total spot count + 10 * number of spotted regions)
Weighted SN: 39 53 43  (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): 86 57 75  

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
2020.12 86.9 84.2 23.1 15.3 (+1.7) 4.72
2021.01 76.0 73.6 10.4 17.3 (+2.0) 4.39
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 31.3 (+3.7) 5.51
2021.08 77.7 79.7 22.0 35.3 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.0 (+4.7) 6.33
2021.10 88.9 88.3 37.4 45.0 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.6 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.7 (+5.1) 6.40
2022.01 103.8 100.5 54.0 (59.5 projected, +3.8) 8.92
2022.02 109.1 106.5 59.7 (65.1 projected, +5.6) 10.46
2022.03 117.0 115.8 78.5 (70.5 projected, +5.4) 10.20
2022.04 130.8 131.7 84.1 (75.7 projected, +5.2) 11.79
2022.05 133.8 136.8 96.5 (82.2 projected, +6.5) 7.48
2022.06 116.1 119.8 70.6 (88.1 projected, +5.9) 8.20
2022.07 131.5 (1)   86.3 (2A) / 102.8 (2B) / 111.3 (2C) (95.3 projected, +7.2) (10.1)
2022.08       (101.9 projected, +6.6)  
2022.09       (106.9 projected, +5.0)  
2022.10       (110.1 projected, +3.2)  
2022.11       (112.9 projected, +2.8)  
2022.12       (117.7 projected, +4.8)  
2023.11       (141.4 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.