*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2019 September 01 06:34UTC Prepared by the Athens Space Weather Forecasting Center *********************************************************************** 1. Solar activity Solar activity was increasing during the past 24 hours. Solar Flux (10.7 cm) measured on 31.08.2019 at 20:00 UTC was 66 sfu. The background X-Ray flux is at the class A6 level. The geomagnetic field was at active to moderate storm (G2) levels on August 31. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at minor storm (G1) levels with Kp=5. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 720 km/s. Solar Wind speed from STEREO A: 380 km/s. Solar Wind speed from STEREO B: --- km/s. The southward component Bz is: 5 nT south. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes An equatorial coronal hole (CH935) of the visible solar disk was in Earth facing position on August 27-29. A high speed stream of solar wind finally arrived some hours earlier than our prediction due to the high solar wind speed. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at active to moderate storm levels on September 1, at unsettled to minor storm levels on September 2 and at quiet to active levels on September 3 due to CH935 effects. Date Estimated Ap index Expected geom. storm 2019.09.01 36 G1 - G2 2019.09.02 22 G1 2019.09.03 14 - *************************************************************************** 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 ***************************************************************************