Viewing archive of Thursday, 20 December 2018
Daily bulletin on solar and geomagnetic activity from the SIDC
Issued: 2018 Dec 20 1230 UTC
SIDC Forecast
Solar flares
Quiet conditions (<50% probability of C-class flares)
Geomagnetism
Active conditions expected (A>=20 or K=4)
Solar protons
Quiet
| 10cm flux | Ap | |
|---|---|---|
| 20 Dec 2018 | 070 | 013 |
| 21 Dec 2018 | 070 | 004 |
| 22 Dec 2018 | 071 | 004 |
Bulletin
The Sun is spotless and did not produce any B class flares or higher in the past 24 hours. The chance for a C flare in the next 24 hours is estimated low. However, former region 2731 (N15W20) produced a couple of small dimmings at 12:00 UT yesterday. But, no associated Earth-directed CMEs were detected in available coronagraph imagery.
The greater than 10 MeV proton flux was at nominal levels in the past 24 hours, and is expected to stay at nominal levels in the next 24 hours.
The solar wind speed near Earth as registered by DSCOVR gradually increased from about 475 to 650 km/s in the past 24 hours, under the influence of a solar wind stream associated with an isolated negative polarity coronal hole. The Interplanetary Magnetic Field (IMF) was predominantly directed towards the Sun and varied between about 5 and 10 nT. Bz varied between 4 and -6 nT. The solar wind speed is expected to begin declining today.
Quiet to unsettled geomagnetic conditions (K Dourbes between 1 and 3; NOAA Kp between 1 and 3) were registered in the past 24 hours. There is a chance for active intervals (K Dourbes = 4) due to the enhanced solar wind speeds. Quiet to unsettled geomagnetic levels are expected over the next 24 hours.
Today's estimated international sunspot number (ISN): 000, based on 12 stations.Solar indices for 19 Dec 2018
| Wolf number Catania | /// |
| 10cm solar flux | 070 |
| AK Chambon La Forêt | 013 |
| AK Wingst | 006 |
| Estimated Ap | 005 |
| Estimated international sunspot number | 000 - Based on 19 stations |
Noticeable events summary
| 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
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