####018002087#### FXXX10 KWNP 301231 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Oct 30 1230 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 5 (NOAA Scale G1). The greatest expected 3 hr Kp for Oct 30-Nov 01 2025 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Oct 30-Nov 01 2025 Oct 30 Oct 31 Nov 01 00-03UT 4.67 (G1) 3.67 2.67 03-06UT 3.67 3.67 2.67 06-09UT 4.33 3.33 2.33 09-12UT 5.33 (G1) 3.00 2.33 12-15UT 5.67 (G2) 3.00 2.33 15-18UT 4.00 3.33 2.33 18-21UT 3.00 3.00 2.33 21-00UT 3.00 3.00 2.00 Rationale: G1-G2 (Minor-Moderate) levels are expected on 30 Oct due to persistent CH HSS 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 30-Nov 01 2025 Oct 30 Oct 31 Nov 01 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 No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Oct 30-Nov 01 2025 Oct 30 Oct 31 Nov 01 R1-R2 5% 5% 10% R3 or greater 1% 1% 1% Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast. ####018002401#### FXXX12 KWNP 301231 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 30 1230 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 was very low. Slight decay was observed in Regions 4266 (N17W44, Cao/beta), 4267 (N03W18, Cso/beta), and 4269 (S11W21, Hrx/alpha). New Region 4271 (S09E61, Axx/alpha) was numbered. Other activity included a partial halo CME off the NE limb beginning at 30/0424 UTC in SOHO/LASCO C2 imagery. The event could be seen behind the NE limb in SUVI 171 imagery beginning at 30/0357 UTC. No Earth-directed CMEs were observed. .Forecast... Solar activity is expected to remain very low with a chance for C-class flares through 31 Oct. C-class flares become likely, with a slight chance for M-class flares, once again on 01 Nov due to the anticipated return of active regions to the eastern limb. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux was at normal to moderate levels. The greater than 10 MeV proton flux was at background levels. .Forecast... The greater than 2 MeV electron flux is expected to reach high levels on 31 Oct - 01 Nov in response to the positive coronal hole (CH) high speed stream (HSS) influence. The greater than 10 MeV proton flux is expected to remain at background levels through 01 Nov. Solar Wind .24 hr Summary... Solar wind conditions continued to reflect positive polarity CH HSS influence. Solar wind speed ranged from approximately 430-585 km/s. Total field ranged from 4-15 nT while the Bz component was between +11/-12 nT. Phi angle was predominantly positive. .Forecast... Solar wind parameters are expected to continue to reflect positive CH/HSS influences through 01 Nov. Geospace .24 hr Summary... The geomagnetic field was at unsettled to G1 (Minor) storm levels due to persistent CH HSS effects. .Forecast... Unsettled to G2 (Moderate) geomagnetic storming is expected on 30 Oct under positive polarity CH HSS effects. Primarily unsettled and active levels are expected on 31 Oct as CH HSS effects continue with quiet to unsettled levels prevailing on 01 Nov.