


Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
331 FXXX12 KWNP 160031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 16 0030 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 continued at moderate levels due to M-class flare activity from Region 4246 (N22W56, Ekc/beta-gamma-delta). Notable flares included an M4.8/2n at 15/0415 UTC, an M3.7/1n at 15/0718 UTC, a long duration M1.1 flare that peaked at 15/1410 UTC, another long duration M2.7 flare at 15/2228 UTC, and an M2.4 flare at 15/2345 UTC. The M4.8 flare had an associated CME off the NW limb in coronagraph imagery beginning at 15/0436 UTC. Modeling efforts showed the ejecta to be on a northward trajectory and not on an Earthward course. The M1.1 flare had an associated Tenflare (peaking at 180 sfu at 15/1524 UTC) observed by SAG USAF RSTN radio stations, as well as two CMEs off the W and NW beginning at 15/1512 UTC. Modelling is underway to determine if there are Earth-directed components. The M2.7 flare also appeared to have ejecta associated with it as seen in SUVI 195 imagery at 15/2200 UTC. Analysis will be conducted as coronagraph imagery becomes available. Region 4246 also produced multiple C-class flares in the past 24h, as it grew and matured its intermediary spots. Region 4248 (N07W27, Eki/beta-gamma-delta) presented no significative change in size or magnetic complexity. Region 4250 (N07W21, Hrx/alpha) continued to decay and lost its trailing spot. Region 4252 (S13E28, Cao/beta) developed a little trailing spot as it rotated towards the center of the solar disk. Region 4254 (N10E60, Hsx/alpha) showed no significant change. .Forecast... Minor to moderate (R1-R2) radio blackouts are likely through 18 Oct, with a slight chance for an isolated R3 (Strong) event, due to the current and potential flare activity of Regions 4246 and 4248. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a maximum flux of 2,850 pfu observed at 15/1540 UTC. The greater than 10 MeV proton flux remained at background levels during this period. .Forecast... The greater than 2 MeV electron flux is expected to decrease to normal to moderate levels on 16 Oct with the CME arrivals and rebound to moderate to high levels on 17-18 Oct. There is a slight chance for a greater than 10 MeV proton event above the S1 (Minor) levels through 18 Oct. Solar Wind .24 hr Summary... Solar Wind parameters were slowly returning to nominal levels as the effect of the negative CH HSS waned. Total interplanetary magnetic field remained at or below 6 nT level during the whole period, with the Bz component between +3/-4 nT. Phi angle was predominantly in the negative sector, as expected during the negative CH HSS influence. Solar wind speeds slowly decreased from about 550 km/s to 485 km/s level. .Forecast... Solar wind parameters are expected to continue gradually waning over the course of 16 Oct as the influence of negative CH HSS reduces. Disturbed solar wind conditions are expected by late on 16 Oct, and continuing through 17 Oct, due to CME arrivals from 11-13 Oct originating from AR 4246. Geospace .24 hr Summary... Geomagnetic field activity was quiet to unsettled with an isolated active period. .Forecast... Geomagnetic field activity will likely reach G2 (Moderate) storm levels late on 16 Oct in response to CMEs that left the Sun over the course of 11-13 Oct affecting the near-Earth environment. G1 (Minor) geomagnetic storm activity is then likely to carry over into 17 Oct. Quiet to unsettled conditions are expected to prevail on 18 Oct as any post CME effects wane.