SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Perth district Date: 11 October, 2026 T-index: 20 Bearings: 0 180 Distance: 0-300 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 60-90 1E 40-90 1 5 10 15 20 25 30 35 40 ** NONE ** UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 4.7 2.6 2.2 FF%. 00 01 5.0 2.9 2.4 FF%%. 01 02 5.2 3.1 2.5 AFF%. 02 03 5.3 3.3 2.6 AFF%. 03 04 5.6 3.3 2.6 AFF%%. 04 05 5.8 3.3 2.6 AFF%%. 05 06 5.7 3.2 2.6 AFF%%. 06 07 5.7 3.1 2.5 AFF%.. 07 08 5.4 2.8 2.3 FFF%. 08 09 5.2 2.5 2.0 AFFF%. 09 10 4.8 1.8 1.6 AFF%%. 10 11 4.2 0.3 0.0 FFFF%.. 11 12 3.8 0.3 0.0 FFF%%. 12 13 3.3 0.3 0.0 FFF%. 13 14 3.2 0.3 0.0 FFF%. 14 15 3.2 0.3 0.0 FFF%. 15 16 3.2 0.3 0.0 FFF%. 16 17 3.1 0.3 0.0 FFF. 17 18 3.0 0.3 0.0 FF%. 18 19 2.9 0.3 0.0 FF%. 19 20 2.7 0.3 0.0 FF%. 20 21 2.8 0.3 0.0 FF%. 21 22 3.6 0.0 0.6 AFF%. 22 23 4.3 2.2 1.8 AFF%. 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) 11-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000