Viewing archive of Monday, 4 September 2017
Daily bulletin on solar and geomagnetic activity from the SIDC
Issued: 2017 Sep 04 1230 UTC
SIDC Forecast
Solar flares
C-class flares expected, (probability >=50%)
Geomagnetism
Quiet (A<20 and K<4)
Solar protons
Quiet
| 10cm flux | Ap | |
|---|---|---|
| 04 Sep 2017 | 115 | 008 |
| 05 Sep 2017 | 115 | 007 |
| 06 Sep 2017 | 115 | 007 |
Bulletin
Solar flaring activity reached moderate levels with an M1.2 flare originating from Catania group 46 (NOAA region 2673) peaking at 05:49UT. This region grew very fast over the last 24 hours and has developed significant complexity with mixed polarity in the intermediate spots. Meanwhile, Catania group 47 (NOAA region 2674) seems to have become less active but remains large and with significant flaring potential. Flaring is expected to continue to occur from both regions with especially Catania group 46 contributing to a significant probability for M flaring. Overall we estimate that C flaring will occur over the next 24 hours and that there is a very significant chance for M flares (45%). No Earth directed CMEs have been observed in coronagraph data. Solar Proton flux levels are at background values and are expected to remain so.
Solar wind speed continued a slow overall decline from around 500 km/s to around 470 km/s. Total magnetic field was in the nominal 3-6nT range with Bz variable and the phi angle mostly in the positive sector. Solar wind is expected to further recover to nominal conditions over the next days. Geomagnetic conditions were quiet to active (local K Dourbes 1-3, NOAA Kp 2-4) and are expected to remain quiet to unsettled over the next days.
Today's estimated international sunspot number (ISN): 120, based on 17 stations.Solar indices for 03 Sep 2017
| Wolf number Catania | /// |
| 10cm solar flux | 120 |
| AK Chambon La Forêt | 015 |
| AK Wingst | 010 |
| Estimated Ap | 009 |
| Estimated international sunspot number | 118 - Based on 28 stations |
Noticeable events summary
| Day | Begin | Max | End | Loc | Strength | OP | 10cm | Catania/NOAA | Radio burst types |
|---|---|---|---|---|---|---|---|---|---|
| 04 | 0536 | 0549 | 0605 | S10W04 | M1.2 | 1F | 46/2673 |
Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive
All times in UTC
Current data suggests there is a moderate possibility for aurora to appear at the following high latitude regions in the near future
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Trondheim
Arkhangelsk
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