:Product: Report of Solar-Geophysical Activity
:Issued: 2026 Apr 15 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 105 Issued at 2200Z on 15 Apr 2026

IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 3 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (16 Apr, 17 Apr,
18 Apr).

IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 390 km/s at 14/2317Z. Total IMF reached 5 nT at
15/0359Z. The maximum southward component of Bz reached -5 nT at
15/1425Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 3248 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on day one (16 Apr), quiet to major
storm levels on day two (17 Apr) and unsettled to major storm levels on
day three (18 Apr).

III.  Event probabilities 16 Apr-18 Apr
Class M    30/30/30
Class X    05/05/05
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           15 Apr 105
Predicted   16 Apr-18 Apr 110/110/110
90 Day Mean        15 Apr 135

V.  Geomagnetic A Indices
Observed Afr/Ap 14 Apr  002/004
Estimated Afr/Ap 15 Apr  004/005
Predicted Afr/Ap 16 Apr-18 Apr  009/008-015/020-025/040

VI.  Geomagnetic Activity Probabilities 16 Apr-18 Apr
A.  Middle Latitudes
Active                20/30/30
Minor Storm           05/35/40
Major-severe storm    01/25/25
B.  High Latitudes
Active                15/05/05
Minor Storm           25/15/15
Major-severe storm    25/80/85