*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2019 May 31 06:48UTC 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 30.05.2019 at 20:00 UTC was 69 sfu. The background X-Ray flux is at the class A7 level. The geomagnetic field was at quiet to unsettled levels on May 30. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at almost quiet levels with Kp=2. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 455 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 south. 3. Solar Energetic Particle Events Protons and electrons are quiet. 4. Coronal Holes A coronal hole (CH919) on the southern hemisphere of the visible solar disk was in Earth facing position on May 24-25. A new small coronal hole (CH920) on the northern hemisphere of the visible solar disk was in Earth facing position on May 26-27. A high speed stream of solar wind noticed on the second half of May 28, possible associated with CH919. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at quiet to unsettled levels on May 31 - June 1 due to CH919 and CH920 effects and at quiet levels on June 2. Date Estimated Ap index Expected geom. storm 2019.05.31 08 - 2019.06.01 06 - 2019.06.02 04 - *************************************************************************** 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 ***************************************************************************