Last update issued on March 7, 2003 at 03:25 UTC.
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[Solar cycles 21-23 (last update March 3, 2003)]
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The geomagnetic field was unsettled to minor storm on March 6. Solar wind speed ranged between 462 and 569 km/sec under the influence of a high speed stream from coronal hole CH24. An additional disturbance may have arrived at 09:45 UTC at ACE.
Solar flux measured at 20h UTC on 2.8 GHz was 150.3. The planetary A
index was 25 (STAR Ap - based on the mean of three hour interval ap indices: 26.4).
Three hour interval K indices: 44445333 (planetary), 43433333 (Boulder).
The background x-ray flux is at the class B4 level.
At midnight there were 6 spotted regions on the visible disk. Solar flare activity was very low.
Region 10295 decayed slowly and quietly.
Region 10296 decayed slowly in all sections. A couple of small negative polarity spots emerged ahead of the huge positive polarity penumbra.
Region 10297 decayed and lost most of the spots it had gained the previous day.
Region 10300 decayed and became spotless, then reemerged with a single spot.
Region 10301 lost several small spots and was otherwise mostly unchanged..
Region 10302 was quiet and stable.
March 4-6: 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 coronal hole (CH24) in the southern hemisphere was in a geoeffective position on March 2-3.
Processed SOHO EIT 284 image at 19:06 UTC on March 6. Any black areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to active on March 7 due to a high speed stream from CH24 with quiet to unsettled likely on March 8-10. 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 to good. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and CPN Radio (Peru).]
|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 SEC/NOAA. 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|
classification was HAX
at midnight, only
negative polarity spots
classification was EKI
at midnight, STAR spot
count includes region
classification was CAO
at midnight, only
negative polarity spots
only negative polarity
spots, these are the
trailing spots of region
classification was CSO
classification was DSO
|Total spot count:||52||41|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2002.09||175.8||109.6||(94.7 predicted, -4.0)|
|2002.10||167.0||97.5||(91.2 predicted, -3.5)|
|2002.11||168.7||95.0||(86.0 predicted, -5.2)|
|2002.12||157.2||81.6||(81.6 predicted, -4.4)|
|2003.01||144.0||79.5||(78.6 predicted, -3.0)|
|2003.02||124.5||46.2||(73.6 predicted, -5.0)|
|2003.03||144.2 (1)||20.7 (2)||(67.9 predicted, -5.7)|
1) Running average based on the daily 20:00 UT observed solar flux value at 2800
2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number is typically 25-45% 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.