:Product: 3-Day Forecast :Issued: 2026 Feb 16 1230 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 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Feb 16-Feb 18 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Feb 16-Feb 18 2026 Feb 16 Feb 17 Feb 18 00-03UT 4.33 3.67 2.67 03-06UT 4.33 3.67 2.67 06-09UT 4.33 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 4.67 (G1) 2.00 2.00 15-18UT 4.00 1.67 0.67 18-21UT 3.67 1.67 2.33 21-00UT 3.00 2.67 3.00 Rationale: Isolated periods of G1 (Minor) geomagnetic storming are likely on 16 Feb due to positive polarity CH HSS influences. 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 Feb 16-Feb 18 2026 Feb 16 Feb 17 Feb 18 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 Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Feb 16 2026 0435 UTC. Radio Blackout Forecast for Feb 16-Feb 18 2026 Feb 16 Feb 17 Feb 18 R1-R2 10% 10% 10% R3 or greater 1% 1% 1% Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio blackouts through 18 Feb.