Subj : 3 Day Space Weather Forecast To : All From : Sean Dennis Date : Thu Mar 26 2026 12:19 am :Product: 3-Day Forecast :Issued: 2026 Mar 26 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # 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 Mar 26-Mar 28 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Mar 26-Mar 28 2026 Mar 26 Mar 27 Mar 28 00-03UT 4.67 (G1) 2.33 1.67 03-06UT 4.67 (G1) 2.67 2.00 06-09UT 4.00 2.00 1.33 09-12UT 2.67 2.00 0.67 12-15UT 2.67 1.67 1.33 15-18UT 3.00 2.00 1.33 18-21UT 2.33 2.00 1.67 21-00UT 2.00 2.33 1.67 Rationale: G1 (Minor) geomagnetic storms are expected on 26 Mar due to a possible glancing blow from a CME that left the Sun on 22 Mar. No further G1 (Minor) or greater geomagnetic storms are expected on 27-28 Mar. 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 Mar 26-Mar 28 2026 Mar 26 Mar 27 Mar 28 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 Mar 26-Mar 28 2026 Mar 26 Mar 27 Mar 28 R1-R2 30% 30% 30% R3 or greater 5% 5% 5% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts, with a slight chance for R3 (Strong) events through 28 Mar. --- MBSE BBS v1.1.7.2 (Linux-x86_64) * Origin: Outpost BBS * Johnson City, TN (1:18/200) .