The geomagnetic field was very quiet on July 15. Solar wind speed at SOHO ranged between 281 and 335 km/s. A moderately strong solar wind shock was observed at DSCOVR at 05:15 UT on July 16, the arrival of the July 14 CME.
Solar flux at 17h UTC on 2.8 GHz was 88.0 (increasing 13.1 over the previous solar rotation, the observation at 17h UT was used due to a minor flux enhancement caused by a C5.8 flare in AR 12665 peaking at 19:36 UT). The average 90 day 10.7 flux at 1 AU was 78.3. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 2.9). Three hour interval K indices: 11000111 (planetary), 11211311 (Boulder)
The background x-ray flux is at the class B2 level.
At the time of counting spots (see image time), spots were observed in 3 active regions using 2K resolution (SN: 60) and in 3 active regions using 1K resolution (SN: 47) SDO images on the visible solar disk.
Region 12665 [S06W59] decayed
slowly producing a number of C flares. Another M class event is still possible.
Region 12666 [N13W46] decayed and could soon become spotless.
Spotted regions not numbered (or interpreted differently)
by SWPC:
New region S5736 [S10E15] was observed with a tiny
spot.
C2+ flares:
| Magnitude | Peak time (UT) | Location | AR | Recorded by | Comment |
| C5.8 | 19:36 | 12665 | GOES15 |
July 13, 15: No obviously Earth directed CMEs were observed in available
LASCO imagery.
July 14: An asymmetric full halo CME was observed after the long duration
M2.4 proton event in AR 12665 early in the day. The CME reached Earth
on July 16.
[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 northern hemisphere coronal hole (CH813) was Earth facing on July 13, however, the coronal hole closed that day due to the development of AR 12666. A small and decaying southern hemisphere coronal hole (CH814) rotated across the central meridian on July 14 and appears to have closed. A recurrent northern hemisphere coronal hole (CH815) will become Earth facing on July 16-19.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is very poor. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be quiet to major storm on July 16-17 due to CME effects and quiet to unsettled on July 18.
| 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 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 detected |
Spot count | Location at midnight | Area | Classification | SDO / HMI 4K continuum image with magnetic polarity overlays |
Comment | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| SWPC | Magnetic (SDO) |
SWPC | STAR | Current | Previous | ||||||
| 2K | 1K | ||||||||||
| 12665 | 2017.07.05 | 12 | 27 | 14 | S05W57 | 0380 | DKI | CKO |
 |
 |
area: 0520 |
| 12666 |
2017.07.11 2017.07.12 |
2 | 2 | 2 | N13W47 | 0010 | AXX | BXO |
 |
 |
|
| S5735 | 2017.07.14 | N15W26 |
 |
||||||||
| S5736 | 2017.07.15 | 1 | 1 | S10E15 | 0005 | AXX |
 |
||||
| Total spot count: | 14 | 30 | 17 | ||||||||
| Sunspot number: | 34 | 60 | 47 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 24 | 40 | 27 | (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): | 37 | 33 | 38 | k * (sunspot number) As of May 7, 2016: k = 1.1 for SWPC, k = 0.55 for MSN 2K, k = 0.80 for MSN 1K (MSN=Magnetic Sunspot Number) |
|||||||
| Month | Average solar flux | International sunspot number (WDC-SILSO) (4) |
Smoothed sunspot number (4) | Average
ap (3) |
|
|---|---|---|---|---|---|
| Measured | 1 AU | ||||
| 2014.02 | 170.3 (cycle peak) |
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 |
| 2016.03 | 91.5 | 90.6 | 54.1 | 50.5 (-2.0) | 10.58 |
| 2016.04 | 93.3 | 94.0 | 38.0 | 47.8 (-2.7) | 9.03 |
| 2016.05 | 93.0 | 95.3 | 52.1 | 44.9 (-2.9) | 11.65 |
| 2016.06 | 81.9 | 84.5 | 20.9 | 41.6 (-3.3) | 8.44 |
| 2016.07 | 86.0 | 88.9 | 32.5 | 38.6 (-3.0) | 9.43 |
| 2016.08 | 85.0 | 87.1 | 50.7 | 36.0 (-2.6) | 9.61 |
| 2016.09 | 87.7 | 88.7 | 44.7 | 33.3 (-2.7) | 14.54 |
| 2016.10 | 86.1 | 85.6 | 33.6 | 31.4 (-1.9) | 15.33 |
| 2016.11 | 78.6 | 76.9 | 21.4 | 29.9 (-1.5) | 9.11 |
| 2016.12 | 75.1 | 72.8 | 18.9 | 28.5 (-1.4) | 9.34 |
| 2017.01 | 77.3 | 74.9 | 25.8 | (27.7 projected, -0.8) | 9.45 |
| 2017.02 | 76.8 | 75.0 | 26.1 | (25.8 projected, -1.9) | 9.58 |
| 2017.03 | 74.6 | 73.9 | 17.7 | (23.2 projected, -2.6) | 14.20 |
| 2017.04 | 80.3 | 80.8 | 32.6 | (21.1 projected, -2.0) | 11.70 |
| 2017.05 | 73.6 | 75.2 | 18.8 | (20.0 projected, -1.1) | 8.09 |
| 2017.06 | 74.7 | 77.1 | 19.4 | (19.0 projected, -1.0) | 6.08 |
| 2017.07 | (82.5) | 12.2 (2A) / 25.2 (2B) / 25.0 (2C) | (17.9 projected, -1.1) | (6.4) | |
1) Running average based on the daily 20:00 UTC observed solar flux value at
2800 MHz.
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.
