Solar Terrestrial Activity Report

Last major update issued on November 30, 2003 at 04:20 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 4, 2003)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 4, 2003)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 4, 2003)]
[Historical solar and geomagnetic data charts 1954-2003 (last update October 15, 2003)]
[Archived reports (last update November 22, 2003)]

Recent activity

The geomagnetic field was quiet to unsettled on November 29. Solar wind speed ranged between 335 and 430 km/sec.

Solar flux measured at 20h UTC on 2.8 GHz was 165.9. The planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 10.0).
Three hour interval K indices: 22233322 (planetary), 22223222 (Boulder).

The background x-ray flux is at the class B6 level.

At midnight there were 10 spotted regions on the visible disk. Solar flare activity was low. A total of 9 C class events were recorded during the day.

Region 10507 decayed slowly and will rotate over the northwest limb late today and early tomorrow. An isolated M class flare is possible as there is still a magnetic delta structure in the northern part of the main penumbra. Flare: C1.9 at 08:34 UTC.
Region 10508 decayed in the northern and western spot sections. Slow development was observed in the south where there is little separating the positive polarity area and an emerging negative polarity area. Flares: C2.0 at 06:38, C1.5 at 06:59, C1.3 at 07:20, C2.6 at 10:12 and C1.6 at 14:48 UTC.
Region 10509 decayed slowly and quietly.
Region 10510 decayed in the leading spot section while slow development was observed in the trailing spots. Flares: C1.5 at 03:30, C2.7 at 18:06 and C4.2/1F at 21:09 UTC.
Region 10511 decayed slowly and quietly.
Region 10513 added a spot in the northeast late in the day, otherwise the region was quiet and stable.
Region 10515 elongated with new leader spots forming. Slow decay was observed where the first spots were visible one day earlier.
Region 10516 developed slowly and quietly.

Spotted regions not numbered by NOAA/SEC:
[S314] This region emerged late on November 29 with two small spots. Location at midnight: S15W04.
[S315] A new region rotated into view at the southeast limb on November 29. Location at midnight: S06E81.

Coronal mass ejections (CMEs)

November 27-29: No partly or fully earth directed CMEs observed.

Coronal holes

Coronal hole history (since late October 2002)
Compare today's report with the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago

A recurrent trans equatorial coronal hole (CH70) will be in a geoeffective position on December 1-2.

Processed SOHO/EIT 284 image at 19:05 UTC on November 29. The darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet to unsettled on November 30 - December 3, a few active intervals are possible on November 30 and December 1 due to a high speed stream from the southernmost extensions of the northern polar coronal hole. On December 4-5 unsettled to major storm conditions are likely due to a high speed stream from coronal hole CH70.

Long distance low frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is fair to poor. Propagation along long distance north-south paths is poor. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant station tonight: WLAM Lewiston ME with another US station noted at times. Radio Vibración (Venezuela) was heard occasionally as well].

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) Material from a CME is likely to impact 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.

Active solar regions (Recent map)

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.

Monthly solar cycle data

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% less.

This report has been prepared by Jan Alvestad. It is based partly on my own observations and analysis, and partly on data from sources noted in solar links. All time references are to the UTC day. Comments and suggestions are always welcome.