|Charts (* = updated daily)||Data and archive|
|Solar wind (*)||Solar and geomagnetic data - last month (*)|
|Electron fluence (*)||Archived daily reports and monthly data from 2003.01 (August 1, 2015)|
|Solar cycle||Solar cycles 23-24 (August 1, 2015)||Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)|
|Cycle 24 progress (August 1, 2015)||Noon SDO sunspot count 1K Reference: 4K (large file) (*)|
|Solar cycles 1-24 (July 17, 2015)||POES auroral activity level October 2009 - December 2012|
|Comparison of cycles 21, 22, 23 and 24 (August 1, 2015)||3rd SSN Workshop, Tucson, 2013|
|Comparison of cycles 12, 13, 14, 16 and 24 (August 1, 2015)||4th SSN Workshop, Locarno, 2014|
|Solar polar fields vs solar cycles (July 18, 2015)|
The geomagnetic field was quiet on August 3, weakly under the decreasing influence of a high speed stream associated with CH679. Solar wind speed at SOHO ranged between 440 and 547 km/s.
Solar flux at 20h UTC on 2.8 GHz was 105.6 (decreasing 27.0 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 119.5. The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 4.9). Three hour interval K indices: 22211111 (planetary), 23322211 (Boulder).
The background x-ray flux is at the class B3 level.
At the time of counting spots (see image time), spots were observed in 14 active regions using 2K resolution (SN: 215) and 12 active regions using 1K resolution (SN: 161) SDO images on the visible solar disk.
Region 12391 [N08W15] decayed slowly and quietly.
Region 12392 [S05W14] reemerged with penumbra spots.
Region 12393 [N18W06] decayed slowly and quietly.
Region 12394 [N11E15] lost penumbral area in the largest spot, however, new flux emerged in the southern part and the region currently has polarity intermixing.
New region 12395 [N12E65] rotated into view on August 2 and was numbered by SWPC the next day.
New region 12396 [S18E57] emerged quickly with many spots. C flares are possible.
Spotted regions not numbered (or interpreted differently) by SWPC:
S4647 [N17W24] decayed slowly and quietly losing most of the leading polarity spots.
S4648 [S22E04] reemerged with a penumbra spot.
S4656 [S06W03] reemerged with a penumbra spot.
S4659 [S12W50] decayed slowly and quietly.
New region S4663 [S10E36] was observed with a penumbra spot.
New region S4664 [S18E37] was observed with a penumbra spot.
New region S4665 [S13W08] emerged with a few spots.
New region S4666 [S06W22] emerged with a penumbra spot.
|Magnitude||Peak time (UTC)||Location||AR||Recorded by||Comment|
August 1-3: No obviously Earth directed CMEs were observed.
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 trans equatorial coronal hole (CH680) was in an Earth facing position on August 3.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is poor to fair.
The geomagnetic field is expected to be quiet on August 4-5. A high speed stream associated with CH680 could cause some unsettled and active intervals on August 6-7.
|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) Compare to the previous day's 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 numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. 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.
|Active region||Date numbered
|Spot count||Location at midnight||Area||Classification||SDO / HMI 4K continuum
image with magnetic polarity overlays
|Total spot count:||12||75||41|
|Sunspot number:||62||215||161||(total spot count + 10 * number of spotted regions)|
|Weighted SN:||32||96||62||(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):||68||118||137||k * (sunspot number)
As of July 1, 2015: k = 1.1 for SWPC, k = 0.55 for MSN 2K, k = 0.85 for MSN 1K (MSN=Magnetic Sunspot Number)
|Month||Average solar flux||International sunspot number
|Smoothed sunspot number (4)||Average
|166.3||146.1 (cycle peak)||110.5 (+1.2)||10.70|
|2014.04||143.9||144.8||112.5||116.4 (+2.1) (solar max)||7.88|
|2015.02||129.1||126.0||66.7||(86.8 projected, -3.0)||9.92|
|2015.03||125.9||124.6||54.5||(83.1 projected, -3.7)||16.14|
|2015.04||128.8||129.7||78.0||(79.8 projected, -3.3)||10.73|
|2015.05||120.0||122.6||90.0||(77.4 projected, -2.4)||8.29|
|2015.06||122.3||126.1||68.3||(73.9 projected, -3.5)||13.15|
|2015.07||107.0||110.8||66.4||(70.2 projected, -3.7)||8.8|
|2015.08||(103.3)||5.9 (2A) / 61.0 (2B) / 82.9 (2C)||(69.0 projected, -1.2)||(7.1)|
1) Running average based on the daily 20:00 UTC observed solar flux value at
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) Updated to new data set from WDC-SILSO on July 1, 2015
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.