####018000994#### AXXX82 KWNP 170031 DAYOBS :Product: Summary of Space Weather Observations dayobs.txt :Issued: 2025 Oct 17 0030 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # https://www.swpc.noaa.gov/content/subscription-services # # Summary of Space Weather Observations # :Solar_Region_Summary: 2025 Oct 16 # Region Location Sunspot Characteristics # Helio Spot Spot Mag. # Num Lat.,CMD Long. Area Extent class count class 4246 N24W69 290 840 14 EKC 30 BGD 4248 N07W41 262 360 12 EKI 18 BG 4250 N05W34 255 10 1 AXX 1 A 4252 S13E14 207 150 4 CSO 5 B 4254 N10E46 175 60 2 HSX 1 A 4255 S08E38 183 10 5 BXO 2 B 4256 S16E66 155 40 7 DAO 5 B ####018002327#### FXXX10 KWNP 170031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Oct 17 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 # # 3-Day Forecast # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Oct 17-Oct 19 2025 is 5.00 (NOAA Scale G1). NOAA Kp index breakdown Oct 17-Oct 19 2025 Oct 17 Oct 18 Oct 19 00-03UT 5.00 (G1) 3.00 4.00 03-06UT 4.67 (G1) 2.33 3.00 06-09UT 3.67 2.00 2.67 09-12UT 3.67 2.00 2.33 12-15UT 3.67 2.00 2.00 15-18UT 3.33 4.00 2.00 18-21UT 3.00 4.00 2.00 21-00UT 2.67 4.33 2.33 Rationale: G1 (Minor) geomagnetic storming is likely on 17 Oct due to glancing CME effects from events that left the Sun on 12/13 Oct. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Oct 17-Oct 19 2025 Oct 17 Oct 18 Oct 19 S1 or greater 10% 10% 5% Rationale: There is a slight chance for a greater than 10 MeV proton event above the S1 (Minor) levels through 18 Oct. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Oct 16 2025 1408 UTC. Radio Blackout Forecast for Oct 17-Oct 19 2025 Oct 17 Oct 18 Oct 19 R1-R2 60% 60% 40% R3 or greater 15% 15% 5% Rationale: 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. Probabilities decrease slightly on 19 Oct as AR 4246 rotates beyond the western limb. ####018003525#### FXXX12 KWNP 170031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 17 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 reached moderate levels with M-class flare activity. Region 4246 (N24W69, Ekc/beta-gamma-delta) continued to be the main culprit for flare activity and continued to exhibit maturing penumbra. Notable flares from this region included a M1.1 at 16/0021 UTC, a M1.3 flare at 16/1408 UTC, a M1.1 flare at 16/1916 UTC, and a M1.0 at 16/2319 UTC. Region 4248 (N07W41, Eki/beta-gamma) was relatively quiet in comparison and little changed. Region 4250 (N05W34, Axx/alpha) underwent the decay of its leading spots. Regions 4255 (S08E38, Bxo/beta) and 4256 (S16E66, Dao/beta) were numbered this period with the latter showing signs of evolution as it rapidly emerged and began forming small asymmetric penumbra. No Earth-directed CMEs were observed in available coronagraph imagery. .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. Probabilities decrease slightly on 19 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 3,769 pfu observed at 16/2015 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 decrease to normal to moderate levels on 17 Oct due to glancing CME effects before returning to high levels on 18-19 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 reflected a mildly disturbed environment perhaps suggesting CME proximity influences. Total field ranged from 2-5 nT, but the Bz component remained at or near neutral. Solar wind speeds gradually decreased for the majority of the period, falling from ~470 km/s to around 400 km/s. However, a minor increase in solar wind speeds back to ranges of 430-450 km/s occurred near 16/2000 UTC. Phi rotated between both positive and negative solar sectors. .Forecast... Additional 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. A trend towards a more nominal environment is then anticipated on 19 Oct. Geospace .24 hr Summary... Geomagnetic field activity was at quiet levels. .Forecast... G1 (Minor) geomagnetic storming is likely on 17 Oct due to glancing CME effects from events that left the Sun on 12/13 Oct. The 15 Oct CMEs that were mentioned in previous discussions were modeled with results suggesting that perhaps 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.