Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
729 FXXX12 KWNP 121231 DAYDIS :Product: Forecast Discussion :Issued: 2026 Sep 12 1230 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # http://www.swpc.noaa.gov/wwire.html # # Forecast Discussion # Solar Activity .24 hr Summary... Solar activity was very low. Regions 4521 (N09W87, Hsx/alpha) and 4524 (N12W37, Hsx/alpha) produced a few B-level enhancements as they moved closer to the western limb. All seven of the numbered regions were either stable or reflected slight decay. No Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity is expected to remain at very low levels, with C-class flares likely and a slight chance of isolated low-level M-class flares (R1-Minor) through 14 Sep. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a maximum flux of 7,008 pfu observed at 11/1355 UTC. The greater than 10 MeV proton flux was at background levels. .Forecast... The greater than 2 MeV electron flux is expected to reach high levels on 12 Sep and decline to low to moderate on 13-14 Sep. The greater than 10 MeV proton flux is expected to remain at background levels. Solar Wind .24 hr Summary... Solar wind conditions remained near-background levels. Total field strength varied between 1-7 nT, the Bz component fluctuated between +/- 6 nT, and solar wind speed averaged close to 425 km/s through the period. The phi angle oscillated between sectors until just after the turn of the UTC day when it remained in a mostly positive orientation. .Forecast... Solar wind conditions could experience minor disturbances on 12 Sep, due mainly to a small, positive polarity CH HSS that is expected to remain geo-effective through the day. Negative CH HSS effects are anticipated to begin late on 13 Sep and last through 14 Sep. Geospace .24 hr Summary... The geomagnetic field was at quiet to unsettled levels. .Forecast... The geomagnetic field is expected to be quiet to unsettled, with isolated active periods possible, on 12-13 Sep as +CH HSS influence is expected to continue. Late on 13 Sep, an anticipated SSBC ahead of a negative polarity coronal hole high speed stream is anticipated to begin influencing the IMF, bringing unsettled to active levels on 14 Sep.