:Product: 0418SGAS.txt :Issued: 2026 Apr 18 0245 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Solar and Geophysical Activity Summary SGAS Number 108 Issued at 0245Z on 18 Apr 2026 This report is compiled from data received at SWO on 17 Apr A. Energetic Events Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0410 0410 0410 140 0419 0420 0420 220 0422 0422 0422 190 0427 0442 0502 4419 N12E29 C4.1 Sf 120 0558 0558 0558 120 0609 0609 0609 110 0612 0612 0612 120 0811 0811 0811 250 1024 1024 1024 100 1518 1518 1518 100 1525 1525 1525 140 1545 1545 1545 110 1938 1938 1938 170 1952 1953 1953 370 2106 2115 2121 B5.9 100 2244 2244 2244 100 B. Proton Events: None C. Geomagnetic Activity Summary: Geomagnetic field activity was quiet. D. Stratwarm: Not Available E. Daily Indices: (real-time preliminary/estimated values) 10 cm 107 SSN 050 Afr/Ap 003/??? X-ray Background B3.4 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 1.8e+06 GT 10 MeV 1.7e+04 p/(cm2-ster-day) (GOES-18 satellite synchronous orbit W137 degrees) Daily Electron Fluence GT 2 MeV 1.00e+08 e/(cm2-ster-day) (GOES-19 satellite synchronous orbit W72 degrees) 3 Hour K-indices: Boulder 0 0 0 1 1 2 2 2 Planetary 1 1 0 1 0 1 2 ? F. Comments: None