SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Albany Perth Date: 20 October, 2026 T-index: 45 Bearings: 331 152 Distance: 386 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 51-60 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 5.7 5.4 3.0 ABB%%. 00 01 6.0 5.9 3.2 BB%%. 01 02 6.3 6.3 3.4 BBB%.. 02 03 6.6 6.5 3.5 ABB%%. 03 04 6.9 6.6 3.5 ABB%%.. 04 05 7.1 6.5 3.5 ABBF%.. 05 06 7.0 6.4 3.5 ABB%%.. 06 07 6.8 6.1 3.3 BBB%%.. 07 08 6.5 5.6 3.1 BBF%%. 08 09 6.4 4.9 2.8 ABFF%%. 09 10 6.0 3.7 2.2 BFF%%.. 10 11 5.3 0.8 0.0 FFFFF%%.. 11 12 4.8 0.8 0.0 FFFF%%.. 12 13 4.2 0.8 0.0 FFFF%.. 13 14 4.0 0.8 0.0 FFF%%. 14 15 3.9 0.8 0.0 FFF%%. 15 16 3.8 0.8 0.0 FFF%.. 16 17 3.7 0.8 0.0 FFF%. 17 18 3.5 0.8 0.0 FFF%. 18 19 3.4 0.8 0.0 FFF%. 19 20 3.2 0.8 0.0 FFF%. 20 21 3.3 0.8 0.0 FFF%. 21 22 4.4 2.8 1.7 AFF%. 22 23 5.2 4.5 2.6 ABF%. 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) 20-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000