:Product: 0601RSGA.txt :Issued: 2025 Jun 01 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 152 Issued at 2200Z on 01 Jun 2025 IA. Analysis of Solar Active Regions and Activity from 31/2100Z to 01/2100Z: Solar activity has been at low levels for the past 24 hours. There are currently 5 numbered sunspot regions on the disk. IB. Solar Activity Forecast: Solar activity is likely to be moderate with a slight chance for an X-class flare on days one, two, and three (02 Jun, 03 Jun, 04 Jun). IIA. Geophysical Activity Summary 31/2100Z to 01/2100Z: The geomagnetic field has been at active to severe storm levels for the past 24 hours. Solar wind speed reached a peak of 1130 km/s at 01/1154Z. Total IMF reached 27 nT at 01/1008Z. The maximum southward component of Bz reached -23 nT at 01/0529Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 666 pfu at 01/0915Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 4397 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at active to severe storm levels on day one (02 Jun), active to minor storm levels on day two (03 Jun) and unsettled to active levels on day three (04 Jun). Protons are expected to cross threshold on day one (02 Jun), are expected to cross threshold on day two (03 Jun) and are likely to cross threshold on day three (04 Jun). III. Event probabilities 02 Jun-04 Jun Class M 65/65/65 Class X 15/15/15 Proton 99/75/60 PCAF yellow IV. Penticton 10.7 cm Flux Observed 01 Jun 150 Predicted 02 Jun-04 Jun 150/150/150 90 Day Mean 01 Jun 154 V. Geomagnetic A Indices Observed Afr/Ap 31 May 012/016 Estimated Afr/Ap 01 Jun 061/124 Predicted Afr/Ap 02 Jun-04 Jun 050/086-023/035-016/018 VI. Geomagnetic Activity Probabilities 02 Jun-04 Jun A. Middle Latitudes Active 10/30/35 Minor Storm 35/35/20 Major-severe storm 55/25/05 B. High Latitudes Active 01/05/10 Minor Storm 05/20/25 Major-severe storm 95/75/55