SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Karratha Perth Date: 16 May, 2025 T-index: 90 Bearings: 184 5 Distance: 1251 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 18-22 1E 5 1 5 10 15 20 25 30 35 40 2F 37-41 2E 14 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.5 10.7 5.7 ASXMMMM MFFF%%... 9.6 6.5 3.5 00 01 16.9 12.7 6.6 SSXMMM MMFFFF%%%. .. 11.0 7.8 4.1 01 02 17.4 13.9 7.1 SSSXMM MMMFFFF%%% ... 11.6 8.6 4.4 02 03 17.5 14.6 7.4 ASSXMM MMMBFFF%%% ... 11.6 9.0 4.5 03 04 17.0 14.9 7.6 ASSXXM MMMBFF%%%. .. 11.3 9.2 4.6 04 05 16.5 14.8 7.5 ASSXXM MMBBFF%%%. .. 11.1 9.1 4.6 05 06 16.4 14.3 7.3 ASSXMM MMMBFF%%%. .. 11.0 8.8 4.5 06 07 16.7 13.4 6.9 SSXXMM MMMFFF%%%. .. 11.1 8.3 4.2 07 08 16.9 11.8 6.2 ASSXMMM MMMFFF%%%. ... 11.1 7.3 3.8 08 09 15.9 8.9 4.9 SXMMMMM MMFFF%%%.. . 10.6 5.3 3.1 09 10 12.8 2.1 0.0 XMMMMMMMMM FF%%%.... 8.7 1.3 0.0 10 11 10.1 2.1 0.0 XMMMMMMMFF %%.... 6.8 1.3 0.0 11 12 8.2 2.1 0.0 XMMMMMMF%% ... 5.7 1.3 0.0 12 13 7.1 2.1 0.0 XMMMMMF%%. . 5.1 1.3 0.0 13 14 6.6 2.1 0.0 XMMMMM%%.. . 4.9 1.3 0.0 14 15 6.2 2.1 0.0 XMMMMF%... 4.7 1.3 0.0 15 16 6.2 2.1 0.0 XMMMMF%... 4.6 1.3 0.0 16 17 5.9 2.1 0.0 XMMMM%%.. 4.4 1.3 0.0 17 18 5.7 2.1 0.0 XMMMM%%.. 4.2 1.3 0.0 18 19 5.4 2.1 0.0 XMMMM%%.. 3.9 1.3 0.0 19 20 5.3 2.1 0.0 XMMMM%%.. 3.8 1.3 0.0 20 21 4.9 2.1 0.0 XMMMM%... 3.6 1.3 0.0 21 22 5.5 2.1 0.0 XMMMM%.. 4.2 1.3 0.0 22 23 10.5 5.4 3.2 SMMMMMFF %%.. 6.9 0.0 2.3 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) 16-May-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000