Last update issued on June 20, 2003 at 03:05 UTC.
[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update June 3, 2003)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update June 3, 2003)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update June 3, 2003)]
[Historical solar and geomagnetic data charts 1954-2003 (last update April 13, 2003)]
[Archived reports (last update June 17, 2003)]
The geomagnetic field was quiet to minor storm on June 19. Solar wind speed ranged between 489 and 644 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz was 122.9. The planetary A
index was 18 (STAR Ap - based on the mean of three hour interval ap indices: 18.5).
Three hour interval K indices: 54433332 (planetary), 33332221 (Boulder - source USAF).
The background x-ray flux is at the class B3 level.
At midnight there were 5 spotted regions on the visible disk. Solar flare activity was very low with no events reaching the C class level.
Region 10385 decayed moderately and was quiet. At the current rate of decay this region will become spotless within a
couple of days.
Region 10386 decayed slowly in the southern spot section. Many new and small spots emerged between the largest penumbrae and the region has become more compact. A major flare is possible.
Region 10387 developed with the largest penumbrae growing. The separation between the positive and negative polarity fields has increased and the region has simplified.
New region 10388 emerged on June 18 and was numbered by SEC the next day.
Spotted regions not numbered by NOAA/SEC:
[S190] A new region emerged to the southwest of region 10386 on June 19. Location at midnight: S13E25.
June 17: A fast full halo CME was observed in LASCO C3 images after the major M class flare in region 10386 late in the day. The CME could reach Earth early on June 20
June 18: A large CME was observed off of the west limb after 09h UTC and was likely associated with an eruption in region 10375 which rotated over the northwest limb a few days ago.
June 19: No obviously geoeffective CMEs observed.
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 new coronal hole (CH45) in the southern hemisphere is developing and will be in a geoeffective position on June 18-19.
Processed SOHO EIT 284 image at 01:06 UTC on June 20. Any black areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to active on June 20 until the possible arrival of the CME observed on June 17. If this CME arrives active to minor storm conditions are likely. Unsettled to active is expected on June 21-23 as a high speed stream from coronal hole CH45 dominates the solar wind.
Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is useless and will likely be useless to very poor until at least June 24. Propagation along north-south paths is poor to fair. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant station tonight: Radio Cristal del Uruguay.]
|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|
|10380||2003.06.07||4||S15W90||0080||CSO||rotated out of view|
classification was DSO
classification was DAC
at midnight, area 0320
classification was DAO
at midnight, area 0240
formerly region S189
classification was DAO
at midnight, area 0080
|Total spot count:||58||86|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2002.12||157.2||80.8||(81.4 predicted, -3.8)|
|2003.01||144.0||79.5||(78.3 predicted, -3.1)|
|2003.02||124.5||46.2||(73.3 predicted, -5.0)|
|2003.03||131.4||61.5||(67.6 predicted, -5.7)|
|2003.04||126.4||60.0||(62.7 predicted, -4.9)|
|2003.05||115.7||55.2||(57.8 predicted, -4.9)|
|2003.06||135.4 (1)||73.2 (2)||(53.8 predicted, -4.0)|
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.