Forecaster summary - Issued 2026-05-22T00:26:18

The high energy electron flux (as measured by GOES19) is expected to remain at High levels (>1000 pfu) for most of Day 1 (22 May,) but is likely to temporarily decrease to Moderate levels. High levels are expected to be reached again through much of Day 2 (23 May), and then mainly at the peak of the diurnal cycle through Day 3 (24 May). Day 4 electron flux levels are expected to decrease to Background to Moderate levels.

The fluence (24 hour integrated flux) has started at Active levels, and is expected to decline below the Active threshold either late Day 2 (23 May) or more likely during Day 3 (24 May), with a decreasing trend thereafter. The MOSWOC REFM model is currently underestimating the observed Active fluence. However, the REFM model is indicating a broadly increasing trend through Days 1 and 2, with a decline through Day 3 (24 May), which is accepted.