Forecaster summary - Issued 2025-06-27T00:14:55

High-energy (≥2 MeV) electron flux observed by GOES-19 has been at background to moderate levels following the onset of fast winds from CH60/-. These ongoing fast winds are likely to result in the charging of the Van Allen belts and as the solar wind pressure gradually eases from today (27 Jun), this enhanced flux is expected to expand outwards towards GEO. This is likely to bring Moderate to High flux levels later Day 2 (28 Jun), and perhaps persistently High flux from Day 3 (29 Jun).

Confidence is high that associated fluence levels will reach Active levels later in the period, but confidence is lower regarding time of onset. There is a chance of Active fluence levels late today (27 Jun), but more likely to reach Active tomorrow onwards (28 to 30 Jun). MOSWOC REFM is showing enhancement above the Active threshold from today, along with recurrence, but confidence is reduced in the timing on Active onset because the current observed fluence trend is opposite to the REFM model and recurrence trends. Therefore a delay of at least 24 hours, for Active levels to be reached, is expected.