SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Geraldton Perth Date: 13 June, 2026 T-index: 75 Bearings: 162 341 Distance: 373 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 51-54 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 6.4 3.6 2.3 BFFF%. 00 01 7.6 4.6 2.8 ABFFF%.. 01 02 8.2 5.1 3.1 BBFFF%. . 02 03 8.3 5.4 3.2 BBFFF%. . 03 04 8.3 5.5 3.3 BBFFF%. . 04 05 8.3 5.5 3.3 BBFFF%. . 05 06 8.4 5.3 3.2 BBFFF%. . 06 07 8.4 4.9 3.0 ABFFFF%. . 07 08 8.2 4.3 2.6 ABFFFF%. . 08 09 7.5 2.9 1.9 AFFFFF%.. 09 10 5.7 0.8 0.0 FFFFF%%.. 10 11 4.3 0.8 0.0 FFFF%.. 11 12 3.6 0.8 0.0 FFF%.. 12 13 3.4 0.8 0.0 FFF%.. 13 14 3.3 0.8 0.0 FFF%. 14 15 3.2 0.8 0.0 FFF%. 15 16 3.3 0.8 0.0 FFF%. 16 17 3.3 0.8 0.0 FFF%. 17 18 3.3 0.8 0.0 FFF%. 18 19 3.3 0.8 0.0 FFF%. 19 20 3.4 0.8 0.0 FFF%.. 20 21 3.2 0.8 0.0 FFF%. 21 22 3.1 0.8 0.0 FFF. 22 23 4.4 0.8 0.0 FFFF%. 23 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT =============================================================================== |. USABLE LESS THAN 50% OF DAYS |% USABLE 50% TO 90% OF DAYS | |B BOTH E and F MODES 90% OF DAYS |M MIXED FIRST AND SECOND F MODES | |F FIRST F MODE ONLY |E E-LAYER PROPAGATION |P 90% E and 50-90% F | |S SECOND MODES ONLY |A HIGH ABSORPTION |X COMPLEX MODES | (c) 13-Jun-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000