:Product: Forecast Discussion :Issued: 2023 Sep 28 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Solar Activity .24 hr Summary... Solar activity reached moderate levels. Region 3450 (S18E60, Cro/Beta) produced an M1 flare at 28/0907 UTC. Region 3435 (N10W71, Dso/Beta) exhibited decay as it became more magnetically simple, losing its delta configuration in its northern intermediate spots. Region 3445 (S13W43, Dai/Beta) and 3447 (S22W25, Dao/Beta) also underwent minor decay, mostly in their intermediate to trailing spots. Region 3449 (N15E27, Cao/Beta-Gamma) continued to show signs of evolution as it grew in overall length and began to form larger spots in its intermediate region. No Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity is expected to be at low levels with a chance for isolated M-class flares through 30 Sep primarily due to ARs 3435 and 3445. Energetic Particles .24 hr Summary... The greater than 2 MeV electron flux reached a peak flux of 3,760 pfu at 27/1620 UTC. The greater than 10 MeV was at background levels. .Forecast... The greater than 2 MeV electron flux will likely reach high levels 28-29 Sep and then return to normal to moderate levels 30 Sep due to CIR influences. The greater than 10 MeV proton flux is expected to continue at background levels with a slight chance for an S1 (Minor) solar radiation event 28 Sep. Chances for an event decrease slightly for 29-30 Sep as AR 3435 moves beyond the western limb. Solar Wind .24 hr Summary... Solar wind parameters reflected possible HSS influences. Total field ranged from 2-7 nT, and the Bz component was +/- 5 nT with no sustained southward deflections. Wind speed accuracy is in question due to low density values, but are likely to be between 400-450 km/s. Phi was mostly positive. .Forecast... A slightly enhanced, yet waning, solar wind environment is anticipated to last through much of 29 Sep. An additional enhancement from a relatively weak CIR is expected by late on 30 Sep. Further enhancements are possible this day as well from any glancing influence from a southerly biased CME that originated from AR 3445 on 25 Sep. Geospace .24 hr Summary... The geomagnetic field was quiet to unsettled. .Forecast... Primarily quiet to unsettled conditions are expected to persist through 29 Sep under HSS effects. Unsettled to active levels are expected for 30 Sep as a CH HSS, and any glancing effects from the aforementioned 25 Sep CME, become geoeffective.