FXXX10 KWNP 231231 DAYTDF :Product: 3-Day Forecast :Issued: 2026 Aug 23 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 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Aug 23-Aug 25 2026 is 2.00 (below NOAA Scale levels). NOAA Kp index breakdown Aug 23-Aug 25 2026 Aug 23 Aug 24 Aug 25 00-03UT 0.67 1.67 1.67 03-06UT 2.00 1.67 1.67 06-09UT 1.67 1.67 1.33 09-12UT 2.00 1.33 1.33 12-15UT 1.33 0.67 1.33 15-18UT 1.33 1.33 1.33 18-21UT 1.67 1.67 1.67 21-00UT 1.67 1.67 1.33 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. 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 Aug 23-Aug 25 2026 Aug 23 Aug 24 Aug 25 S1 or greater 25% 10% 10% Rationale: There is a chance for the greater than 10 MeV proton flux to reach S1 (Minor) levels on 23 Aug, and a slight chance on 24-25 Aug. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Aug 23-Aug 25 2026 Aug 23 Aug 24 Aug 25 R1-R2 45% 45% 45% R3 or greater 10% 10% 10% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts, and a slight chance for an R3 (Strong) or greater event, over 23-25 Aug.