####018002292#### FXXX10 KWNP 190031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Oct 19 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 6 (NOAA Scale G2). The greatest expected 3 hr Kp for Oct 19-Oct 21 2025 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Oct 19-Oct 21 2025 Oct 19 Oct 20 Oct 21 00-03UT 4.33 2.67 2.67 03-06UT 4.00 3.67 3.00 06-09UT 4.67 (G1) 2.67 2.67 09-12UT 3.67 2.67 1.67 12-15UT 3.33 3.00 1.67 15-18UT 3.00 1.67 1.00 18-21UT 2.67 2.00 1.00 21-00UT 3.33 2.67 1.67 Rationale: Periods of G1 (Minor) geomagnetic storming are expected on 18 Oct due continued CME influences, followed by CIR effects. 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 19-Oct 21 2025 Oct 19 Oct 20 Oct 21 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. 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 18 2025 1051 UTC. Radio Blackout Forecast for Oct 19-Oct 21 2025 Oct 19 Oct 20 Oct 21 R1-R2 65% 50% 35% R3 or greater 5% 5% 5% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an R3 (Strong) or greater event, on 18 Oct as Region 4246 transits the west limb. On 19-20 Oct, there is a chance for isolated R1-R2 events. ####018002444#### FXXX12 KWNP 190031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 19 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 high levels. Region 4246 (N25W93, Dki/beta) produced five M-class (R1-Minor) flares over the past 24 hours and was observed to be in decay as it transited the west limb. New Region 4258 (S16W40, Bxo/beta) was numbered, while the remaining regions were stable. No Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity is expected to remain low, with a chance for isolated R1-R2 events (R1-R2/Minor-Moderate, over 19-21 Oct. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux decreased to normal to moderate levels. The greater than 10 MeV proton flux remained at background levels throughout the period. .Forecast... The greater than 2 MeV electron flux is expected to return to high levels on 19-21 Oct. The greater than 10 MeV proton flux is expected to remain at background levels. Solar Wind .24 hr Summary... Solar Wind parameters were enhanced throughout the period, likely due to glancing influences from CMEs that departed the Sun between 13-15 Oct. Total magnetic field strength reached 21 nT, while the Bz component reached as far south as -12 nT. Solar wind speeds increased from a low of around 370 km/s to a peaks above 550 km/s after 18/1500 UTC. The phi angle was variable throughout the period. .Forecast... Enhanced solar wind conditions are expected to persist through 20 Oct. On 19 Oct, the onset of CIR effects preceding a negative polarity CH HSS are expected. Negative polarity CH HSS influences are expected to dominate over 19-21 Oct. Geospace .24 hr Summary... The geomagnetic field reached G2 (Moderate) storm levels in response to glancing CME influences from eruptions that departed the Sun between 13-15 Oct. .Forecast... Periods of active conditions and G1 (Minor) storming are expected on 19 Oct due continued CME influences, followed by CIR effects. Additional periods of active conditions are likely on 20-21 Oct as negative polarity CH HSS effects prevail. ####018000994#### AXXX82 KWNP 190031 DAYOBS :Product: Summary of Space Weather Observations dayobs.txt :Issued: 2025 Oct 19 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 18 # Region Location Sunspot Characteristics # Helio Spot Spot Mag. # Num Lat.,CMD Long. Area Extent class count class 4246 N25W93 288 300 8 DKI 5 B 4248 N07W66 261 380 10 DKI 7 B 4252 S12W14 209 160 5 CSO 6 B 4254 N10E20 175 90 2 HSX 1 A 4256 S15E40 155 140 6 DAO 6 B 4257 S10E60 135 150 5 HSX 2 A 4258 S16W40 235 10 4 BXO 8 B