:Product: Report of Solar-Geophysical Activity
:Issued: 2026 May 13 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 133 Issued at 2200Z on 13 May 2026

IA.  Analysis of Solar Active Regions and Activity from 12/2100Z to
13/2100Z: Solar activity has been at low levels for the past 24 hours.
There are currently 4 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 (14 May, 15 May,
16 May).

IIA.  Geophysical Activity Summary 12/2100Z to 13/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 520 km/s at 13/1341Z. Total IMF reached 13
nT at 13/1132Z. The maximum southward component of Bz reached -8 nT at
13/1243Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 518 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (14 May), active to major
storm levels on day two (15 May) and unsettled to minor storm levels on
day three (16 May).

III.  Event probabilities 14 May-16 May
Class M    40/40/40
Class X    05/05/05
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           13 May 103
Predicted   14 May-16 May 105/100/100
90 Day Mean        13 May 125

V.  Geomagnetic A Indices
Observed Afr/Ap 12 May  002/004
Estimated Afr/Ap 13 May  010/011
Predicted Afr/Ap 14 May-16 May  010/012-022/030-018/024

VI.  Geomagnetic Activity Probabilities 14 May-16 May
A.  Middle Latitudes
Active                30/35/35
Minor Storm           10/40/30
Major-severe storm    01/20/15
B.  High Latitudes
Active                20/05/05
Minor Storm           35/20/25
Major-severe storm    30/75/65