|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 (June 1, 2023)|
|Solar cycle||Solar cycles 23-25 (June 1, 2023)||Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)|
|Cycle 24-25 progress (June 1, 2023)||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 (June 1, 2023)||3rd SSN Workshop, Tucson, 2013|
|Comparison of cycles 12-14, 16, 24-25 (June 1, 2023)||4th SSN Workshop, Locarno, 2014|
|Solar polar fields vs. solar cycles (May 29, 2023)||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|
The geomagnetic field was quiet to unsettled on June 20, weakly under the influence of effects related to CH1153/CH1154. Solar wind speed at SOHO ranged between 387 and 462 km/sec. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.
Solar flux density measured at 20h UT on 2.8 GHz was 180.1 - increasing 16.0 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 144.04. In comparison SC24 peaked on June 28, 2014 at 145.50). The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 8.1). Three hour interval K indices: 32122223 (planetary), 33213322 (Boulder), 45234325 (Andenes).
The background x-ray flux is at the class C2 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 16 active regions using 2K resolution (SN: 412) and in 15 active regions using 1K resolution (SN: 254) SDO/HMI images.
Region 13333 [S11W46] decayed slowly and
was mostly quiet.
Region 13334 [N17W15] was quiet and stable.
Region 13335 [S14W19] decayed slightly and was mostly quiet.
Region 13336 [S21W16] has many tiny spots and was mostly quiet.
Region 13338 [N11E03] decayed slowly and quietly
Region 13339 [S19E30] developed slightly as the large penumbra became irregular and new spots emerged in the south.
Region 13340 [N22E32] decayed slowly and was mostly quiet.
Region 13341 [S15E61] produced a number of flares including an X1 event peaking at 17:09. A faint halo signature was observed with the CME observed after the event. The main ejecta is headed well away from Earth, however, minor components of the CME could reach Earth on June 23 or 24.
Region 13342 [S22W73] developed further and could produce further M class flares while rotating over the southwest limb today and tomorrow. C1 flares: C1.8 @ 10:17 UT
New region 13344 [N23W46] emerged on June 19 and was numbered by SWPC the next day as the region continued to develop slowly.
New region 13345 [N09E59] emerged on June 19 with SWPC numbering the region the following day. C flares are possible.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S8676 [S12E56] was quiet and stable.
S8682 [N17E33] was mostly quiet and stable.
New region S8685 [N08E37] emerged with a few spots.
New region S8686 [S12E80] rotated into view with a small spot.
New region S8687 [S27E45] emerged with tiny spots.
|Magnitude||Peak time (UT)||Location||Source||Recorded by||Comment|
|C4.7||03:32||13341||GOES16||incorrectly attributed to AR 13333 by SWPC
simultaneous flare in AR 13342
|C5.9||04:54||13340||GOES16||incorrectly attributed by SWPC to small flare in AR 13342|
|C2.5||07:07||13341||GOES16||simultaneous flare in AR 13340|
|C5.7||13:09||13341||GOES16||attributed by SWPC to smaller, simultaneous flare in AR 13342|
|C4.9||14:41||13342||GOES16||incorrectly attributed by SWPC to AR 13339|
|C6.9||15:34||13342||GOES16||incorrectly attributed by SWPC to AR 13341|
|X1.1||17:09||13341||GOES16||CME. Weak type IV and moderate type II radio sweeps|
June 18-19: No obviously Earth directed CMEs were
June 20: A CME associated with X1 flare at 17:09 UT in AR 13341 may have Earth directed components. In that case a weak shock and unsettled to minor storm intervals are possible on June 23-24.
[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 trans equatorial coronal hole (CH1155) could become Earth facing on June 23.
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 to fair.
Quiet to unsettled geomagnetic conditions are expected for June 21 due to weak effects from CH1153 and CH1154. Quiet conditions are likely on June 22. If any components of the June 20 CME are Earth direct, unsettled to minor storm conditions are possible on June 23-24.
|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.
(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
|Spot count||Location at midnight||Area||Classification||SDO / HMI 4K continuum
image with magnetic polarity overlays
SWPC added a duplicate region on June 19, AR 13343
|13343||2023.06.19||N16W14||this is a duplicate of AR 13334|
|Total spot count:||65||252||104|
|Sunspot number:||155||412||254||(total spot count + 10 * number of spotted regions)|
|Weighted SN:||110||314||166||(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):||171||227||203|
|Month||Average solar flux||International sunspot number
|Smoothed sunspot number (4)||Average ap
|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|
(Solar minimum using 365d smoothing:
November 17, 2019)
(ISN 13 months smoothed
|2022.12||147.9||143.4||112.8||(105.8 projected, +4.8)||10.99|
|2023.01||182.4||176.6||143.6||(112.2 projected, +6.4)||8.73|
|2023.02||167.2||163.2||110.9||(117.0 projected, +4.8)||14.48
|2023.03||157.2||155.6||122.6||(120.1 projected, +3.1)||14.42|
|2023.04||145.4||146.4||96.4||(125.5 projected, +5.4)||13.40|
|2023.05||155.6||159.2||137.9||(131.2 projected, +5.7)||10.67|
|2023.06||161.6 (1)||87.9 (2A) / 131.9 (2B) / 168.8 (2C)||(134.3 projected, +3.1)||(8.1)|
|2023.07||(133.8 projected, -0.5)|
|2023.08||(134.8 projected, +1.0)|
|2023.09||(138.2 projected, +3.4)|
|2023.10||(140.1 projected, +1.9)|
|2023.11||(142.7 projected max SC25)|
|2023.12||(142.6 projected, -0.1)|
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
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.