*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 December 11 07:39UTC Prepared by the Athens Space Weather Forecasting Center *********************************************************************** 1. Solar activity Solar activity was almost stable during the past 24 hours. Solar Flux (10.7 cm) measured on 10.12.2018 at 20:00 UTC was 71 sfu. The background X-Ray flux is at the class A4 level. The geomagnetic field was at quiet to unsettled levels on December 10. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at almost quiet levels with Kp=2. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 545 km/s. Solar Wind speed from STEREO A: 380 km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 2 nT south. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes An equatorial coronal hole (CH898) was in Earth facing position on December 4-6. A high speed stream of solar wind reached Earth as it was predicted with minor geomagnetic impact. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at quiet levels, with a chance for unsettled intervals, on December 11-13. Date Estimated Ap index Expected geom. storm 2018.12.11 05 - 2018.12.12 04 - 2018.12.13 04 - *************************************************************************** Athens Space Weather Forecasting Center Physics Department, National & Kapodistrian University of Athens Athens Neutron Monitor Station A.NE.MO.S Tel.: +30 210 727 6901 email: spaceweather@phys.uoa.gr URL: http://spaceweather.phys.uoa.gr ***************************************************************************