Last major update issued on November 18, 2006 at 04:25 UTC.
geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 12, 2006)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 12, 2006)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 12, 2006)]
[Historical solar and geomagnetic data charts 1954-2005 (last update March 3, 2006)]
[Archived reports (last update November 12, 2006)]
The geomagnetic field was quiet on November 17. Solar wind speed ranged between 308 and 359 km/s (all day average 337 km/s - decreasing 45 km/s from the previous day).
Solar flux measured at 20h UTC on 2.8 GHz was 89.5. The planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 4.9). Three hour interval K indices: 22112101 (planetary), 23113111 (Boulder).
The background x-ray flux is at the class A3 level.
At midnight there were 3 spotted regions on the visible solar disk. The solar flare activity level was very low. No C class events were recorded during the day.
Region 10923 decayed further and was quiet.
Region 10924 decayed slowly and quietly.
Region 10925 decayed in the leader spot section while new trailing spots emerged. Some slight polarity intermixing is evident in the trailing spot section.
November 15-17: No obvious partly or fully Earth directed CMEs were detected in LASCO imagery.
Coronal hole history (since late October 2002)
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago
A recurrent coronal hole, CH248, in the southern hemisphere could rotate into an Earth facing position on November 19-22. Only the northernmost extensions are marginally within potentially geoeffective positions, so there is a chance the associated high speed stream will not reach Earth.
Processed SOHO/EIT 284 image at 01:06 UTC on November 18. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet on November 18-21. There is a chance a high speed stream from CH248 could arrive on November 22 or 23 and cause occasional unsettled and active intervals until November 25.
|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: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability.
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor to fair. Propagation on long distance northeast-southwest paths is poor.
Monitoring remarks from a location near N58E06: Most of the observed signals from North America were from stations on Newfoundland and in Florida. The best TA signals were from stations in Puerto Rico (580 kHz was unusually good), Venezuela and Colombia, particularly on frequencies in the lower half of the MW band.
Compare to the previous day's image.
Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SEC. 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 SEC or where SEC has observed no spots. SEC active region numbers in the table below and in the active region map above are the historic SEC/USAF numbers.
|Active region||Date numbered||SEC
|Location at midnight||Area||Classification||Comment|
|10923||2006.11.08||2||1||S05W48||0510||CHO||classification was HHX at midnight|
|10925||2006.11.14||2||6||S05E11||0020||HRX||classification was DAO at midnight, area 0040|
|Total spot count:||8||11|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2006.05||80.9||22.2||(16.8 predicted, -0.3)|
|2006.06||76.5||13.9||(15.1 predicted, -1.7)|
|2006.07||75.7||12.2||(13.2 predicted, -1.9)|
|2006.08||79.0||12.9||(12.7 predicted, -0.5)|
|2006.09||77.8||14.5||(12.6 predicted, -0.1)|
|2006.10||74.3||10.4||(11.5 predicted, -1.1)|
|2006.11||90.2 (1)||21.5 (2)||(10.1 predicted, -1.4)|
1) Running average based on the
daily 20:00 UTC observed solar flux
value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC) sunspot number. The official international sunspot number is typically 30-50% lower.
This report has been prepared by Jan Alvestad. It is based partly on my own observations and analysis, and partly on data from some of these solar data sources. All time references are to the UTC day. Comments and suggestions are always welcome.