Last update issued on July 3, 2003 at 03:30 UTC. Sunspot region update posted at 11:44 UTC.
[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update July 2, 2003)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update July 2, 2003)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update July 2, 2003)]
[Historical solar and geomagnetic data charts 1954-2003 (last update April 13, 2003)]
[Archived reports (last update July 2, 2003)]
The geomagnetic field was quiet to active on July 2. Solar wind speed ranged between 452 and 617 km/sec. The high speed stream from the eastern part of coronal hole CH46 dominated the solar wind after 19h UTC.
Solar flux measured at 20h UTC on 2.8 GHz was 134.8. The planetary A
index was 15 (STAR Ap - based on the mean of three hour interval ap indices: 15.9).
Three hour interval K indices: 13343343 (planetary), 13333333 (Boulder).
The background x-ray flux is at the class B4 level.
At midnight there were 5 spotted regions on the visible disk. Solar flare activity was moderate. A total of 4 C and 1 M class events was recorded during the day. A C1.3 flare at 12:08 UTC was optically uncorrelated.
Region 10390 decayed slowly and quietly.
Region 10397 lost its magnetic delta structure but is still a complex region with a large degree of polarity intermixing. Further M class flares are likely. Flares: M3.0/1F at 07:28 and C1.7 at 23:07 UTC.
Region 10398 developed a few new spots and was quiet.
Region 10399 decayed slowly and quietly.
Region 10400 developed slowly and was somewhat unstable. There is not much separating positive and negative polarity spots in the southern part of the region. Flares: C1.6 at 15:46 and C5.4 at 22:22 UTC.
June 30-July 2: No LASCO images available. There is a serious problem with the SOHO high gain antenna. New LASCO images and nearly all other SOHO data is expected to be unavailable until about July 14.
July 2: An M3 flare in region 10397 may have been associated with a possibly geoeffective CME. If there was a CME it could reach Earth between noon on July 4 and July 5.
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
Large extensions of the southern polar coronal hole (CH46) mainly were in geoeffective positions from late on June 24 until July 2.
Processed GOES SXI coronal structure image at 17:00 UTC on July 2. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be unsettled to active on July 3-5 with a possibility of occasional minor storm intervals due to a high speed stream from coronal hole CH46.
Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is very poor. Propagation along north-south paths is fair. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant station tonight: none, Radio Cristal del Uruguay and 2 stations presumed to be from Argentina (both covering the soccer match between Santos (Brazil) and Boca Juniors (Argentina)) were about equal strength. ]
|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.
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.
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.
|Solar region||Date numbered||SEC
|Location at midnight||Area||Classification||Comment|
|10396||2003.06.27||3||S05W83||0070||CSO||rotated out of view|
|Total spot count:||63||74|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2003.01||144.0||79.7||(79.7 predicted, -2.3)|
|2003.02||124.5||46.0||(74.7 predicted, -5.0)|
|2003.03||131.4||61.1||(69.0 predicted, -5.7)|
|2003.04||126.4||60.0||(64.1 predicted, -4.9)|
|2003.05||115.7||55.2||(59.2 predicted, -4.9)|
|2003.06||129.3||77.4||(55.2 predicted, -4.0)|
|2003.07||133.0 (1)||9.4 (2)||(51.6 predicted, -3.6)|
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 interpretations, and partly on data from sources noted in solar links. All time references are to the UTC day. Comments and suggestions are always welcome.