:Product: 0617RSGA.txt
:Issued: 2025 Jun 17 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 168 Issued at 2200Z on 17 Jun 2025

IA.  Analysis of Solar Active Regions and Activity from 16/2100Z to
17/2100Z: 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 expected to be moderate
with a chance for X-class flares on days one, two, and three (18 Jun, 19
Jun, 20 Jun).

IIA.  Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 540 km/s at 17/0031Z. Total IMF reached 9
nT at 16/2250Z. The maximum southward component of Bz reached -6 nT at
17/1232Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1156 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on days one and two (18 Jun, 19 Jun) and
quiet to minor storm levels on day three (20 Jun). Protons have a slight
chance of crossing threshold on days one, two, and three (18 Jun, 19
Jun, 20 Jun).

III.  Event probabilities 18 Jun-20 Jun
Class M    75/75/75
Class X    25/25/25
Proton     10/10/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           17 Jun 139
Predicted   18 Jun-20 Jun 150/150/150
90 Day Mean        17 Jun 148

V.  Geomagnetic A Indices
Observed Afr/Ap 16 Jun  010/ NA
Estimated Afr/Ap 17 Jun  008/010
Predicted Afr/Ap 18 Jun-20 Jun  014/017-010/012-018/024

VI.  Geomagnetic Activity Probabilities 18 Jun-20 Jun
A.  Middle Latitudes
Active                30/30/35
Minor Storm           15/15/25
Major-severe storm    05/01/05
B.  High Latitudes
Active                15/15/10
Minor Storm           30/30/25
Major-severe storm    50/40/65
