Solar activity on UT day 21-May is expected to be at R0-R1 levels. S0 solar radiation storm conditions are expected. The solar wind speed is expected to be strong. G0 geomagnetic conditions are expected, with a chance of G1 due to coronal hole high speed wind stream effects. HF radio propagation conditions are expected to be normal to fair. Maximum usable frequencies (MUFs) in the Australian region are expected to be near predicted monthly values to 15% depressed. Shortwave fadeouts are possible.