


Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
314 FXXX10 KWNP 291231 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Aug 29 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 29-Aug 31 2025 is 2.67 (below NOAA Scale levels). NOAA Kp index breakdown Aug 29-Aug 31 2025 Aug 29 Aug 30 Aug 31 00-03UT 2.33 1.67 2.67 03-06UT 2.00 1.33 2.00 06-09UT 1.33 1.33 2.33 09-12UT 1.33 1.33 2.33 12-15UT 1.00 1.33 2.33 15-18UT 0.67 1.33 2.33 18-21UT 0.67 1.67 2.33 21-00UT 1.00 1.67 2.67 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 29-Aug 31 2025 Aug 29 Aug 30 Aug 31 S1 or greater 50% 25% 10% Rationale: There exists a chance for S1 (Minor) solar radiation storms on 29-30 Aug, and a slight chance on 31 Aug. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Aug 28 2025 2040 UTC. Radio Blackout Forecast for Aug 29-Aug 31 2025 Aug 29 Aug 30 Aug 31 R1-R2 75% 75% 75% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are expected, with a slight chance for R3 (Strong) or greater events, over 29-31 Aug.