*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2019 April 21 06:55UTC 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 20.04.2019 at 20:00 UTC was 70 sfu. The background X-Ray flux is at the class A8 level. The geomagnetic field was at quiet levels on April 20. 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: 335 km/s. Solar Wind speed from STEREO A: 375 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 A new small coronal hole (CH915) on the southern hemisphere of the visible solar disk will be in Earth facing position on April 19-22. A high speed stream of solar wind from this CH is expected on the first half of April 23. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at very quiet levels on April 21-22 and at quiet to unsettled levels on April 23 due to CH915 effects. Date Estimated Ap index Expected geom. storm 2019.04.21 04 - 2019.04.22 03 - 2019.04.23 07 - *************************************************************************** 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 ***************************************************************************