*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 August 22 07:56UTC 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 21.08.2018 at 20:00 UTC was 68 sfu. The background X-Ray flux is at the class A2 level. The geomagnetic field was at quiet to unsettled levels on August 21. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at unsettled levels with Kp=3. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 500 km/s. Solar Wind speed from STEREO A: 380 km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 1 nT north. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes A coronal hole (CH881) was in Earth facing position on August 16-19. A high speed stream of solar wind finally reached Earth on the first half of August 20. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at very quiet levels, with a chance for unsettled intervals, on August 22-23 due to CH881 effects and at quiet levels on August 24. Date Estimated Ap index Expected geom. storm 2018.08.22 04 - 2018.08.23 03 - 2018.08.24 03 - *************************************************************************** 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 ***************************************************************************