*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2019 December 23 06:48UTC Prepared by the Athens Space Weather Forecasting Center *********************************************************************** 1. Solar activity Solar activity was decreasing stable during the past 24 hours. Solar Flux (10.7 cm) measured on 22.12.2019 at 20:00 UTC was 71 sfu. The background X-Ray flux is at the class < A1 level. The geomagnetic field was at quiet levels on December 22. 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: 340 km/s. Solar Wind speed from STEREO A: --- km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 0 nT. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes A new small coronal hole (CH948) on the southern hemisphere of the visible solar disk will be in Earth facing position on Dec. 21-22. If this CH will be geoeffective the first effects are expected on the second half of Dec. 24. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at very quiet levels on December 23 and at quiet to unsettled levels, with a chance for active intervals, on December 24-25 due to CH948 weak effects. Date Estimated Ap index Expected geom. storm 2019.12.23 02 - 2019.12.24 05 - 2019.12.25 08 - *************************************************************************** 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 ***************************************************************************