SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Carnarvon Perth Date: 19 August, 2026 T-index: 65 Bearings: 165 344 Distance: 815 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 29-34 1E 10 1 5 10 15 20 25 30 35 40 2F 49-54 2E 22 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 8.9 7.9 3.9 AXMMMF%% .. 6.6 4.6 2.7 00 01 9.9 9.3 4.5 SXMMMB% %.. 7.3 5.5 3.1 01 02 10.1 10.2 4.9 SXMMMMB %%.. 7.6 6.0 3.3 02 03 10.3 10.7 5.1 ASXMMMB %%.. 7.8 6.3 3.5 03 04 10.2 10.9 5.2 ASXMMMB %%.. 7.9 6.4 3.5 04 05 10.1 10.9 5.1 ASXMMMB %%.. 7.9 6.4 3.5 05 06 10.0 10.6 5.0 SXXMMMP %... 7.8 6.2 3.4 06 07 9.8 10.0 4.8 SXMMMMP %.. 7.7 5.8 3.3 07 08 9.5 9.0 4.4 ASXMMMB% %.. 7.5 5.2 3.0 08 09 9.3 7.2 3.7 AXMMMMF% %.. 7.1 4.1 2.5 09 10 8.0 1.4 0.0 MMMMMMM%%% .. 6.1 0.8 0.0 10 11 6.4 1.4 0.0 MMMMMM%%.. . 5.0 0.8 0.0 11 12 5.4 1.4 0.0 MMMMM%%.. 4.3 0.8 0.0 12 13 4.8 1.4 0.0 MMMMM%.. 4.0 0.8 0.0 13 14 4.6 1.4 0.0 MMMMM%.. 3.8 0.8 0.0 14 15 4.5 1.4 0.0 MMMM%.. 3.7 0.8 0.0 15 16 4.3 1.4 0.0 MMMM%.. 3.7 0.8 0.0 16 17 4.2 1.4 0.0 MMMM%.. 3.6 0.8 0.0 17 18 4.1 1.4 0.0 MMMM%.. 3.5 0.8 0.0 18 19 4.0 1.4 0.0 MMMM%.. 3.4 0.8 0.0 19 20 3.8 1.4 0.0 MMMM%. 3.3 0.8 0.0 20 21 3.6 1.4 0.0 MMMM.. 3.1 0.8 0.0 21 22 3.8 1.4 0.0 MMMM.. 3.3 0.8 0.0 22 23 6.4 4.5 2.4 AMMMF%.. 5.1 2.6 1.6 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) 19-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000