SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Carnarvon Perth Date: 31 August, 2026 T-index: 90 Bearings: 165 344 Distance: 815 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 29-35 1E 10 1 5 10 15 20 25 30 35 40 2F 50-55 2E 22 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 10.2 8.4 4.3 ASMMMMFF %%. 7.6 5.0 2.9 00 01 11.1 9.8 4.8 SXMMMMF F%%.. 8.3 5.8 3.3 01 02 11.4 10.7 5.2 ASXMMMM F%%.. 8.7 6.3 3.5 02 03 11.5 11.2 5.4 ASXMMMM B%%.. 8.9 6.6 3.7 03 04 11.5 11.4 5.5 ASXMMMM B%%.. 9.0 6.7 3.7 04 05 11.4 11.3 5.5 ASXMMMM B%%.. 9.0 6.7 3.7 05 06 11.0 11.0 5.3 ASXMMMM P%%.. 8.7 6.5 3.6 06 07 10.6 10.4 5.1 ASXMMMM %%.. 8.5 6.1 3.5 07 08 10.5 9.5 4.7 SXMMMMM %%.. 8.3 5.5 3.2 08 09 10.2 7.8 4.0 AXMMMMMF %%.. 8.0 4.5 2.8 09 10 9.2 2.8 1.7 AMMMMMMF% %.. 7.2 0.0 1.5 10 11 7.7 1.5 0.0 MMMMMMM%%% .. 6.1 0.9 0.0 11 12 6.6 1.5 0.0 MMMMMM%%.. 5.3 0.9 0.0 12 13 6.0 1.5 0.0 MMMMMM%.. 4.9 0.9 0.0 13 14 5.6 1.5 0.0 MMMMM%%.. 4.6 0.9 0.0 14 15 5.4 1.5 0.0 MMMMM%.. 4.4 0.9 0.0 15 16 5.1 1.5 0.0 MMMMM%.. 4.3 0.9 0.0 16 17 5.0 1.5 0.0 MMMMM%.. 4.2 0.9 0.0 17 18 4.7 1.5 0.0 MMMMM%. 4.0 0.9 0.0 18 19 4.5 1.5 0.0 MMMM%.. 3.8 0.9 0.0 19 20 4.2 1.5 0.0 MMMM%.. 3.6 0.9 0.0 20 21 4.0 1.5 0.0 MMMM%. 3.5 0.9 0.0 21 22 4.6 1.5 0.0 MMMM%.. 3.9 0.9 0.0 22 23 7.5 5.6 3.0 AXMMMF%.. 5.9 3.3 2.0 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) 31-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000