Solar flare activity on UT day 20-Apr is expected to be at the R0 level. S0 solar proton conditions are expected. The solar wind speed is expected to be strong to moderate over the UT day. G0 geomagnetic conditions, with a chance of G1, are expected. HF radio propagation conditions are expected to be fair to poor across the Australian region. Maximum Usable Frequencies (MUFs) in the Australian region are expected to be depressed by 15-20% relative to predicted monthly values.