Last major update issued on January 29, 2014 at 05:15 UTC.
[Solar and geomagnetic data - last month (updated
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update January 1, 2014)] [Cycle 24 progress (last update January 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update January 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update January 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update January 1, 2014)]
[POES auroral activity level since October
2009 - updated January 26, 2013]
[Solar polar fields vs solar cycles - updated January 11, 2014]
[Presentation 3rd SSN Workshop, Tucson, 2013 (pdf)]
The geomagnetic field was quiet on January 28. Solar wind speed at SOHO ranged between 276 and 414 km/s. A weak low speed stream from CH601 arrived after noon and caused only a minor increase in geomagnetic activity.
Solar flux at 20h UTC on 2.8 GHz was 157.2 (decreasing 2.4 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 146.5. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.4). Three hour interval K indices: 00110122 (planetary), 00222222 (Boulder).
The background x-ray flux is at the class C1 level.
At the time of counting spots (see image time) spots were observed in 12 active regions in 2K resolution (SN: 219) and 10 active regions in 1K resolution (SN: 156) SDO images on the visible solar disk.
Region 11959 [S23W61] decayed slowly and quietly.
Region 11960 [S16W56] decayed further losing all trailing polarity spots and penumbral area in the leading polarity spots.
Region 11963 [S09W34] was quiet and stable. A small patch of positive polarity flux emerged within the trailing spot section.
Region 11964 [S16W39] was quiet and stable.
Region 11965 [S15W16] was quiet and stable.
Region 11967 [S12E70] is a large and complex region with polarity intermixing and a magnetic delta structure in the southern part of the largest spot (the magnetic delta structure is at the location where most of the flares occur). A major flare is possible. C5+ flares: C7.6 at 00:31, M1.5 at 04:09, C9..2 at 05:29, M3.6 at 07:31, C8.3 at 12:25, M1.3 at 12:46, M4.9/1F at 19:40, M2.6/1F at 22:16 UTC.
Region 11968 [N10E68] could produce a minor M class flare. C5+ flare: C8.5 at 16:45 UTC (AR 11967 flared simultaneously but with shorter duration than AR 11968).
Spotted regions not numbered (or interpreted differently) by SWPC:
S3065 [S13W47] lost the spots early in the day, then reemerged with penumbra spots late in the day.
New region S3070 [N13E28] emerged with a penumbra spot.
New region S3071 [S08E22] emerged with a penumbra spot.
New region S3072 [S15W28] emerged with penumbra spots.
New region S3073 [N20E73] emerged with a penumbra spot.
January 26-28: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
Coronal hole history (since October
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago
A small northern hemisphere coronal hole (CH601) was in an Earth facing position on January 25.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is fair. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be quiet on January 29-31 with a chance of a few unsettled intervals on January 29 due to effects from CH601.
|Coronal holes (1)||Coronal mass ejection (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
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.
(Click on image for 2K resolution) Compare to the previous day's image. 0.5K image
When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.
Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. 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 SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.
|Active region||Date numbered
|Spot count||Location at midnight||Area||Classification||SDO / HMI 4K continuum
image with magnetic polarity overlay
previous SWPC location: S06W25
previous SWPC location: S14W28
merged with AR 11966
|11966||2014.01.25||S12W15||merged with AR 11965|
|Total spot count:||30||99||56|
|Sunspot number:||70||219||156||(total spot count + 10 * number of spotted regions)|
|Weighted SN:||55||124||81||(Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)|
|Relative sunspot number (Wolf number):||42||77||86||k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for STAR SDO 2K, k = 0.55 for STAR SDO 1K|
|Month||Average measured solar flux||International sunspot number (SIDC)||Smoothed sunspot number||Average ap
|2011.11||153.5 (cycle peak)||96.7 (cycle peak)||61.1 (+1.2)||5.55|
possible cycle 24 max
|2013.07||115.5||57.0||(65.4 projected, +2.8)||9.47|
|2013.08||114.6||66.0||(67.8 projected, +2.4)||8.27|
|2013.09||102.6||36.9||(70.1 projected, +2.3)||5.23|
|2013.10||132.1||85.6||(70.0 projected, -0.1)||7.71|
|2013.11||148.3||77.6||(68.1 projected, -1.9)||5.68|
|2013.12||147.7||90.3||(67.4 projected, -0.7)||4.68|
|2014.01||157.0 (1)||115.8 (2A) / 128.2 (2B) / 104.8 (2C)||(67.6 projected, +0.2)||(5.6)|
1) Running average based on the daily 20:00 UTC observed solar flux value at
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official SIDC international sunspot number is typically 30-50% lower. 2B) Boulder SN current month average to date. 2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international Potsdam WDC ap indices.
This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to the UTC day. Comments and suggestions are always welcome.
SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.