


Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
373 FXXX10 KWNP 080031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Oct 08 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 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Oct 08-Oct 10 2025 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Oct 08-Oct 10 2025 Oct 08 Oct 09 Oct 10 00-03UT 4.67 (G1) 3.00 1.67 03-06UT 4.33 2.67 1.67 06-09UT 4.67 (G1) 2.00 1.67 09-12UT 3.00 1.67 1.33 12-15UT 2.00 1.33 1.33 15-18UT 2.00 1.33 1.33 18-21UT 2.67 1.67 1.33 21-00UT 3.00 1.67 1.33 Rationale: Periods of G1 (Minor) geomagnetic storming are likely on 08 Oct due to the anticipated arrival of two slow-moving CMEs that left the Sun on 03 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 08-Oct 10 2025 Oct 08 Oct 09 Oct 10 S1 or greater 5% 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 08-Oct 10 2025 Oct 08 Oct 09 Oct 10 R1-R2 35% 30% 30% R3 or greater 10% 5% 5% Rationale: A moderate chance for R1-R2 (Minor-Moderate) radio blackouts due to M-class flare activity, with a slight chance for an isolated R3 (Strong) event, will persist through 08 Oct. Probabilities undergo a minor decrease on 09-10 Oct as Region 4236 exits the western limb.