SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Carnarvon Perth Date: 3 April, 2026 T-index: 50 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 9.0 8.3 4.1 ASMMMM%% %.. 6.7 4.9 2.7 00 01 9.8 9.5 4.6 SXMMMB% %%.. 7.3 5.6 3.1 01 02 10.1 10.3 4.9 SXXMMMB %%.. 7.6 6.1 3.3 02 03 10.3 10.8 5.1 SSXMMMB %%... 7.8 6.3 3.4 03 04 10.4 11.0 5.2 ASXMMMB P%... 8.0 6.5 3.5 04 05 10.7 10.9 5.1 ASXMMMM %%%.. 8.3 6.4 3.5 05 06 10.5 10.7 5.0 SXXMMMM %%%.. 8.2 6.3 3.4 06 07 10.4 10.1 4.8 SXMMMMM %%%.. 8.1 5.9 3.3 07 08 10.2 9.2 4.4 ASXMMMMF %%.. 7.8 5.4 3.0 08 09 9.9 7.7 3.8 AXMMMMM% %%.. 7.5 4.5 2.6 09 10 8.3 4.3 2.3 AMMMMMM%% %.. 6.3 2.2 1.7 10 11 6.6 1.4 0.0 MMMMMMM%%. . 5.1 0.8 0.0 11 12 5.6 1.4 0.0 MMMMMM%... 4.5 0.8 0.0 12 13 4.9 1.4 0.0 MMMMM%.. 4.1 0.8 0.0 13 14 4.8 1.4 0.0 MMMMM%.. 4.0 0.8 0.0 14 15 4.9 1.4 0.0 MMMMM%. 4.1 0.8 0.0 15 16 4.8 1.4 0.0 MMMMM%. 4.0 0.8 0.0 16 17 4.8 1.4 0.0 MMMMM%. 4.0 0.8 0.0 17 18 4.7 1.4 0.0 MMMMM%. 3.9 0.8 0.0 18 19 4.6 1.4 0.0 MMMM%.. 3.9 0.8 0.0 19 20 4.3 1.4 0.0 MMMM%.. 3.6 0.8 0.0 20 21 3.9 1.4 0.0 MMMM%. 3.3 0.8 0.0 21 22 4.3 1.4 0.0 MMMM%. 3.6 0.8 0.0 22 23 6.7 5.9 3.1 SMMM%%. 5.2 3.4 2.1 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) 3-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000