Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
906 FXXX12 KWNP 261231 DAYDIS :Product: Forecast Discussion :Issued: 2026 Sep 26 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 low, with only C-class flares observed, both from Region 4534 (N10W90, Cro/beta). Of the eight numbered regions on disk, Region 4542 (S19W07, Bxi/beta) was the only group to exhibit growth this period. Region 4539 (S10, L=13) decayed to plage, and all remaining regions were either stable or in decay. No Earth-directed CMEs were observed. .Forecast... Solar activity is likely to reach low levels on 26-27 Sep, while very low levels are anticipated for 28 Sep, with a slight chance for an isolated M-flare (R1-R2/Minor-Moderate) through 28 Sep. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux was at normal to moderate levels. The greater than 10 MeV proton flux was steady at background levels. .Forecast... The greater than 2 MeV electron flux is expected to be at normal to moderate levels on 26 Sep, before increasing to high levels on 27-28 Sep. The greater than 10 MeV proton flux is expected to persist at background levels through 28 Sep. Solar Wind .24 hr Summary... Solar wind parameters reflected continued positive polarity CH HSS influences. Total magnetic field strength reached a peak of 9 nT and then gradually decreased to end the period at 4 nT. The Bz (north-south) component varied between +7/-8 nT. Solar wind speeds varied between 450 km/s and 557 km/s in the first half of the reporting period before maintaining an average of 475 km/s in the later half. The phi angle was predominantly positive (away from the Sun). .Forecast... A mildly enhanced solar wind environment is expected to continue on 26-27 Sep as CH HSS influences gradually subside. Background solar wind conditions are expected to return on 28 Sep. Geospace .24 hr Summary... The geomagnetic field was at active levels through much of the period due to positive polarity CH HSS influences. .Forecast... The geomagnetic field is expected to reach active levels on 26 Sep, followed by quiet to unsettled levels on 27 Sep, as positive polarity CH HSS influences gradually diminish. Mostly quiet conditions are expected to prevail on 28 Sep.