=================================== Weekly Space Weather Highlights =================================== Highlights of Solar and Geomagnetic Activity 10 - 16 September 2018 Solar activity was very low throughout the period. Region 2722 (S07, Lo=215, class/area Bxo/10 on 11 Sep) produced the strongest flare of the period, a B1 flare at 11/0759 UTC. The region decayed to plage in the following days. No Earth-directed CMEs were observed in available coronagraph imagery. No proton events were observed at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit ranged from normal background to high levels. High levels were reached on 12-16 Sep and moderate levels were reached on 10-11 Sep. All enhancements in electron flux are associated with the influence of a positive polarity CH HSS. Geomagnetic field activity ranged from quiet to G2 (Moderate) geomagnetic storm levels. The onset of a CIR ahead of a positive polarity CH HSS on 10 Sep increased geomagnetic activity to G1 levels. As wind speeds increased to around 550 km/s on 11 Sep, geomagnetic activity further increased to G2 (Moderate) geomagnetic storm levels. Total magnetic field strength (Bt) peaked at 15 nT late on 10 Sep. Bt then decreased to near 5-6 nT by mid-day on 11 Sep, which decreased the geomagnetic response to mostly quiet to active levels. One additional period of isolated G1 (Minor) geomagnetic storming was observed early on 14 Sep. Wind speeds persisted at elevated levels through 16 Sep, with a notable increase to a peak around 650 km/s observed early on 15 Sep. As wind speeds decreased, quiet to unsettled levels on 15 Sep gave way to quiet levels on 16 Sep. Forecast of Solar and Geomagnetic Activity 17 September - 13 October 2018 Solar activity is expected to be very low throughout the outlook period. No proton events are expected at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at moderate levels on 06-08 Oct and at high levels for the remainder of the outlook period. All enhancements in electron flux are expected due to multiple, recurrent CH HSSs. Geomagnetic field activity is expected to range from quiet to G2 (Moderate) geomagnetic storm levels. G2 (Moderate) geomagnetic storm levels are expected on 08 Oct; G1 (Minor) geomagnetic storm levels are expected on 07 Oct and 10 Oct; active conditions are expected on 17 Sep, 23 Sep, 02 Oct and 11 Oct; unsettled conditions are expected on 18 Sep, 24 Sep, 01 Oct, 09 Oct and 12 Oct. All levels of elevated geomagnetic activity are due to the anticipated influence of multiple, recurrent CH HSSs.