===================================== NOAA 3 Day Space Weather Forecast ===================================== The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale G2). The greatest expected 3 hr Kp for Apr 20-Apr 22 2018 is 6 (NOAA Scale G2). NOAA Kp index breakdown Apr 20-Apr 22 2018 Apr 20 Apr 21 Apr 22 00-03UT 4 4 3 03-06UT 5 (G1) 4 3 06-09UT 6 (G2) 3 2 09-12UT 6 (G2) 3 1 12-15UT 5 (G1) 2 1 15-18UT 3 2 1 18-21UT 3 2 2 21-00UT 4 3 2 Rationale: G2 (Moderate) geomagnetic storm levels were observed during the first half of the UTC day on day one (20 Apr) with G1 (Minor) geomagnetic storm levels expected during the rest of the UTC day. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-15 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 20-Apr 22 2018 Apr 20 Apr 21 Apr 22 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 Apr 20-Apr 22 2018 Apr 20 Apr 21 Apr 22 R1-R2 1% 1% 1% R3 or greater 1% 1% 1% Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.