*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 July 23 05:56UTC 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 22.07.2018 at 20:00 UTC was 68 sfu. The background X-Ray flux is at the class A2 level. The geomagnetic field was at very quiet levels on July 22. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at very quiet levels with Kp=0. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 445 km/s. Solar Wind speed from STEREO A: 460 km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 1 nT south. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes A new coronal hole (CH876) on the southern hemisphere of the visible solar disk will be in Earth facing position on July 21-22. A high speed stream of solar wind from CH876 is expected to reach Earth on the first half of July 24. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at very quiet levels on July 23 and quiet to minor storm levels on July 24-25. Date Estimated Ap index Expected geom. storm 2018.07.23 03 - 2018.07.24 21 G1 2018.07.25 18 G1 *************************************************************************** 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 ***************************************************************************