*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 April 18 04:39UTC 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 17.04.2018 at 20:00 UTC was 69 sfu. The background X-Ray flux is at the class A2 level. The geomagnetic field was at very quiet levels on April 17. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at quiet levels with Kp=1. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 285 km/s. Solar Wind speed from STEREO A: 400 km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 3 nT south. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes A new equatorial coronal hole (CH861) will be in Earth facing position on April 16-18. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at very quiet levels on April 18 and at quiet to active levels on April 19-20 due to CH861 effects. Date Estimated Ap index Expected geom. storm 2018.04.18 04 - 2018.04.19 12 - 2018.04.20 10 - *************************************************************************** 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 ***************************************************************************