:Product: 3-Day Forecast :Issued: 2026 Jul 23 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 3 (below NOAA Scale levels). The greatest expected 3 hr Kp for Jul 23-Jul 25 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Jul 23-Jul 25 2026 Jul 23 Jul 24 Jul 25 00-03UT 2.00 3.67 2.67 03-06UT 2.00 4.67 (G1) 2.33 06-09UT 2.67 4.33 2.00 09-12UT 2.67 4.00 1.33 12-15UT 2.00 2.33 1.33 15-18UT 2.00 2.33 1.67 18-21UT 3.00 3.00 2.00 21-00UT 3.33 2.67 2.33 Rationale: G1 (Minor) geomagnetic storms are likely for 24 Jul due to CME 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 Jul 23-Jul 25 2026 Jul 23 Jul 24 Jul 25 S1 or greater 5% 5% 5% 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 Jul 23-Jul 25 2026 Jul 23 Jul 24 Jul 25 R1-R2 55% 55% 55% R3 or greater 10% 10% 10% Rationale: Solar activity is expected to be low with further M-class flares (R1-R2/Minor-Moderate) likely on 23-25 Jul primarily due to the flare potential of AR 4493.