*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 August 23 07:27UTC 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 22.08.2018 at 20:00 UTC was 67 sfu. The background X-Ray flux is at the class A2 level. The geomagnetic field was at very quiet to unsettled levels on August 22. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at quiet levels with Kp=1. A faint CME observed on August 20 at 21:24UT and our prediction using model EAMv2 for the arrival of the shock is for August 25 at 01:08UT. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 395 km/s. Solar Wind speed from STEREO A: 350 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 23 due to CH881 effects and at quiet to unsettled levels on August 24-25 with a chance for active intervals. Date Estimated Ap index Expected geom. storm 2018.08.23 03 - 2018.08.24 04 - 2018.08.25 05 - *************************************************************************** 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 ***************************************************************************