Forecaster summary - Issued 2018-09-17T00:00:42

The high energy electron flux will on average remain above the Active threshold through the period, and peak well above the 10,000 pfu level on Days 1 and 2. However, later in the period flux levels may dip below the threshold during the diurnal minima. The corresponding 24-hour fluence will likely also remain above the Active threshold through the period, and above Very Active at least on Days 1 and 2. There is however reduced confidence on Days 3 and 4. This is reflected in the REFM model which suggests a flat or declining trend, but with a wide model spread. The 27-day recurrence also suggests above Active levels through the period with the next high speed solar wind stream expected to have only a small impact upon the fluence levels.