SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 17 May, 2026 T-index: 60 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 12-14 1E 2 1 5 10 15 20 25 30 35 40 2F 28-31 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 16.4 12.5 7.2 SSSMMM MMFFFF%%%. ... 10.4 7.9 4.4 00 01 18.5 14.4 8.2 ASSSXM MMMBFFFF%% %.... 11.6 9.4 4.9 01 02 18.1 15.6 8.7 SSSXX MMMMBFFF%% %%.... 11.9 10.2 5.2 02 03 17.6 16.3 9.1 SSSSX MMMMBBF%%% %..... 11.5 10.7 5.3 03 04 17.3 16.5 9.2 SSSSX MMMBBBF%%% %..... 11.3 10.9 5.4 04 05 16.8 16.3 9.1 SSSSX MMMBBB%%%% %.... 11.3 10.8 5.3 05 06 17.0 15.7 8.8 SSSXX MMMBBF%%%% %..... 11.2 10.4 5.1 06 07 17.3 14.6 8.3 ASSSXM MMMBFFF%%% %...... 11.2 9.7 4.8 07 08 16.9 12.7 7.4 SSSXMM MMMFFF%%%% %..... 11.0 8.5 4.3 08 09 15.6 9.0 5.5 SSMMMMM MMFFF%%%%. .... 10.3 6.0 3.2 09 10 11.9 2.2 0.0 XMMMMMMMMM F%%%%..... 8.3 1.5 0.0 10 11 9.6 2.2 0.0 XMMMMMMMF% %%...... 6.5 1.5 0.0 11 12 8.0 2.2 0.0 XMMMMMM%%% ..... 5.5 1.5 0.0 12 13 7.3 2.2 0.0 XMMMMMF%%. .... 5.1 1.5 0.0 13 14 7.0 2.2 0.0 XMMMMM%%%. ... 4.9 1.5 0.0 14 15 6.5 2.2 0.0 XMMMMM%%.. .. 4.9 1.5 0.0 15 16 6.6 2.2 0.0 XMMMMM%%%. .. 4.9 1.5 0.0 16 17 6.4 2.2 0.0 XMMMMM%%.. .. 4.7 1.5 0.0 17 18 6.2 2.2 0.0 XMMMMM%%.. .. 4.5 1.5 0.0 18 19 5.9 2.2 0.0 XMMMM%%%.. .. 4.2 1.5 0.0 19 20 5.7 2.2 0.0 XMMMM%%%.. .. 3.9 1.5 0.0 20 21 5.3 2.2 0.0 XMMMM%%... . 3.9 1.5 0.0 21 22 6.4 2.2 0.0 XMMMMF%%.. . 4.6 1.5 0.0 22 23 12.9 8.3 5.2 SSMMMMF FF%%%... 7.9 4.1 3.4 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) 17-May-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000