SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Geraldton Perth Date: 12 October, 2026 T-index: 20 Bearings: 162 341 Distance: 373 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 52-60 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 5.2 4.5 2.7 ABF%. 00 01 5.5 5.0 3.0 ABB%.. 01 02 5.6 5.4 3.2 BB%%. 02 03 5.9 5.6 3.3 BB%%. 03 04 6.2 5.7 3.3 BBF%.. 04 05 6.3 5.7 3.3 BBF%%. 05 06 6.3 5.5 3.2 BBF%%. 06 07 6.2 5.3 3.1 BBF%.. 07 08 6.0 4.9 2.9 ABF%%. 08 09 5.8 4.3 2.6 ABF%%. 09 10 5.3 3.2 2.0 ABFF%.. 10 11 4.7 0.6 0.0 FFFF%%.. 11 12 4.1 0.6 0.0 FFFF%.. 12 13 3.6 0.6 0.0 FFF%.. 13 14 3.4 0.6 0.0 FFF%. 14 15 3.5 0.6 0.0 FFF%. 15 16 3.4 0.6 0.0 FFF%. 16 17 3.3 0.6 0.0 FFF%. 17 18 3.2 0.6 0.0 FFF%. 18 19 3.0 0.6 0.0 FF%.. 19 20 2.8 0.6 0.0 FF%. 20 21 2.9 0.6 0.0 FF%. 21 22 3.9 0.6 0.0 FFF%.. 22 23 4.8 3.7 2.3 BF%.. 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) 12-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000