*********************************************************************** Product: Daily Forecast of Geomagnetic Activity Issued: 2018 March 19 07:36UTC 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 18.03.2018 at 20:00 UTC was 69 sfu. The background X-Ray flux is at the class A2 level. The geomagnetic field was at quiet to moderate storm levels on March 18. No obviously Earth directed CMEs were observed in available LASCO imagery. The Kp index now is at active levels with Kp=4. 2. Solar Wind Geomagnetic Activity Solar Wind speed from ACE: 585 km/s. Solar Wind speed from STEREO A: 385 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 A coronal hole (CH857) which extended from close to the equator up to mid-heliographic latitudes was in Earth facing position on March 10-15. A large area on the visible solar disk has characteristics of coronal hole. This area will affect the geomagnetic conditions on March 21-25. 5. Geophysical Activity Forecast The geomagnetic field is expected to be at unsettled to minor storm levels on March 19 and at quiet to active levels on March 20-21 due to CH857 effects. Date Estimated Ap index Expected geom. storm 2018.03.19 15 G1 2018.03.20 13 - 2018.03.21 17 - *************************************************************************** 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 ***************************************************************************