SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Perth district Date: 2 October, 2026 T-index: 50 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 5.5 2.7 2.3 FFF%. 00 01 5.9 3.0 2.5 AFF%%. 01 02 6.1 3.2 2.6 AFFF%. 02 03 6.4 3.4 2.7 AFFF%.. 03 04 6.7 3.4 2.8 AFFF%%. 04 05 6.8 3.4 2.8 AFFF%%. 05 06 6.6 3.3 2.7 AFFF%%. 06 07 6.4 3.2 2.6 AFFF%.. 07 08 6.1 2.9 2.4 FFFF%. 08 09 5.9 2.5 2.1 FFF%%. 09 10 5.3 1.7 1.6 AFFF%.. 10 11 4.7 0.4 0.0 FFFF%%.. 11 12 4.2 0.4 0.0 FFFF%.. 12 13 3.8 0.4 0.0 FFF%%. 13 14 3.7 0.4 0.0 FFF%.. 14 15 3.7 0.4 0.0 FFF%. 15 16 3.6 0.4 0.0 FFF%. 16 17 3.5 0.4 0.0 FFF%. 17 18 3.4 0.4 0.0 FFF%. 18 19 3.2 0.4 0.0 FFF%. 19 20 3.1 0.4 0.0 FFF. 20 21 3.1 0.4 0.0 FFF. 21 22 3.8 0.4 0.0 FFF%. 22 23 4.8 2.2 1.9 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) 2-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000