Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
690 FXXX12 KWNP 180031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 18 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 increased to high levels due to numerous M-class flares (R1-Minor) observed from Region 4246 (N24W81, Ekc/beta-gamma-delta). As this region approached the W limb, some intermediate spot decay was observed. Region 4248 (N07W54, Eki/beta-gamma) was quiet while slight decay in spot number was observed. Region 4256 (S15E52, Cso/beta) was also quiet and indicated some minor penumbra growth in the leader spot. Region 4257 (S08E75, Hsx/alpha) was numbered this period. An active filament was noted in the vicinity of Region 4250 (N05W34, Axx/alpha) near 17/0520 UTC. No ejecta associated with this event has been noted in available coronagraph imagery. No other potentially Earth-directed CMEs have been observed. .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 flare potential of Regions 4246 and 4248. Probabilities decrease slightly on 19-20 Oct as AR 4246 rotates beyond the western limb. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a maximum flux of 3,330 pfu observed at 17/1700 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 18 Oct due to glancing CME effects before returning to high levels on 19-20 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 at nominal levels until 17/0930 UTC, when an enhancement occurred in the IMF. This is possibly due to glancing effects of a CME from 13-15 Oct. Total field increased from 6-12 nT and the Bz component became further southward from -3 to -9 nT. Total field further increased after 17/2020 UTC reaching 14 nT. Solar wind speeds remained near 380 km/s. Phi was in a mostly negative orientation through about 17/1600 UTC when a switch to a positive orientation occurred. .Forecast... Possible enhancements are anticipated through 18 Oct due to glancing CME influences from events that left the Sun primarily over the course of 13-15 Oct followed by a transition into a negative polarity CH HSS on 19 Oct. Geospace .24 hr Summary... Geomagnetic field activity was at quiet to unsettled levels. .Forecast... The 15 Oct CMEs that were mentioned in previous discussions were modeled with results suggesting that a glancing blow at Earth is possible by late on 18 Oct. However, the bulk of the material should be well ahead of Earths orbit. Therefore, unsettled to active geomagnetic activity, with a chance for G1 (Minor) storming, is expected on 18 Oct with any glancing CME effects causing these activity levels to carry over into the early portions of 19 Oct. A transition into a negative polarity CH HSS is expected on 19 Oct causing further unsettled to active conditions.