*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2019 September 24 05:17UTC 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 23.09.2019 at 20:00 UTC was 66 sfu. The background X-Ray flux is at the class A6 level. The geomagnetic field was at very quiet levels on September 23. 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: 310 km/s. Solar Wind speed from STEREO A: 540 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 An equatorial coronal hole (CH937) was in Earth facing position on 20-21 September. No high speed stream of solar wind has been detected yet. A new equatorial coronal hole (CH938) will be in Earth facing position on September 24-25. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at quiet to active levels on September 24-25 due to CH937 effects and at quiet to unsettled levels on September 26. Date Estimated Ap index Expected geom. storm 2019.09.24 10 - 2019.09.25 08 - 2019.09.26 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 ***************************************************************************