Issued: 2017 Apr 08 1230 UTC
C-class flares expected, (probability >=50%)
Active conditions expected (A>=20 or K=4)
Quiet
| 10cm flux | Ap | |
|---|---|---|
| 08 Apr 2017 | 072 | 018 |
| 09 Apr 2017 | 072 | 016 |
| 10 Apr 2017 | 070 | 013 |
Solar activity was at low levels during the period. Three C-class flares were recorded, the strongest being a C4.3 event at 19:49UT. These flares originated from NOAA 2645's trailing portion, which has rotated over the west limb. The Sun is currently spotless. A small active region, responsible for a B3 flare at 01:48UT, is about to rotate over the east limb. No earth-directed coronal mass ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10MeV proton flux was at nominal levels.
An isolated C-class flare remains possible.
Around 17UT, solar wind speed started a gradual increase from its nominal 420 km/s to end the period at 570 km/s and still climbing. Bz fluctuated between -8 and +6 nT. The interplanetary magnetic field was initially directed towards the Sun, but became variable after 17UT to end the period in a steady towards direction. The particle stream from a narrow extension from the positive polar coronal hole may affect the earth environment on 9 or 10 April.
The geomagnetic field was at quiet to unsettled levels, with active episodes (Kp=4) during 21UT-03UT and 06-09UT. Dourbes geomagnetic data were missing for most of the period, but Wingst and Niemegk showed an active episode around midnight too. The geomagnetic field is expected to be at quiet to active levels, in response to particle streams from various coronal holes.
Today's estimated international sunspot number (ISN): 000, based on 23 stations.
| Wolf number Catania | 034 |
| 10cm solar flux | 074 |
| AK Chambon La Forêt | 017 |
| AK Wingst | 012 |
| Estimated Ap | 012 |
| Estimated international sunspot number | 023 - Based on 30 stations |
| Day | Begin | Max | End | Loc | Strength | OP | 10cm | Catania/NOAA | Radio burst types | |
|---|---|---|---|---|---|---|---|---|---|---|
| None | ||||||||||
Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive
All times in UTC
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