:Product: 0516RSGA.txt
:Issued: 2025 May 16 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 136 Issued at 2200Z on 16 May 2025

IA.  Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: 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 likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(17 May, 18 May, 19 May).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 489 km/s at 16/0721Z. Total IMF reached 9
nT at 16/1804Z. The maximum southward component of Bz reached -7 nT at
16/1842Z.  Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 455 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (17 May) and active to minor
storm levels on days two and three (18 May, 19 May).

III.  Event probabilities 17 May-19 May
Class M    60/55/55
Class X    20/15/15
Proton     05/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           16 May 117
Predicted   17 May-19 May 118/118/120
90 Day Mean        16 May 162

V.  Geomagnetic A Indices
Observed Afr/Ap 15 May  015/ NA
Estimated Afr/Ap 16 May  009/011
Predicted Afr/Ap 17 May-19 May  013/ NA-021/ NA-021/ 10

VI.  Geomagnetic Activity Probabilities 17 May-19 May
A.  Middle Latitudes
Active                30/40/40
Minor Storm           10/25/25
Major-severe storm    01/05/05
B.  High Latitudes
Active                15/10/10
Minor Storm           25/25/25
Major-severe storm    40/60/60
