:Product: 0510RSGA.txt
:Issued: 2024 May 10 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 131 Issued at 2200Z on 10 May 2024

IA.  Analysis of Solar Active Regions and Activity from 09/2100Z to
10/2100Z: Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a X3 event observed at
10/0654Z from Region 3664 (S17W48). There are currently 7 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be high on
days one, two, and three (11 May, 12 May, 13 May).

IIA.  Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic
field has been at quiet to severe storm levels for the past 24 hours.
Solar wind speed reached a peak of 754 km/s at 10/1917Z. Total IMF
reached 52 nT at 10/1745Z. The maximum southward component of Bz reached
-46 nT at 10/1740Z.  Protons greater than 10 MeV at geosynchronous orbit
reached a peak level of 206 pfu at 10/1745Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 176 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at active to severe storm levels on day one (11 May), unsettled to
major storm levels on day two (12 May) and unsettled to active levels on
day three (13 May). Protons are expected to cross threshold on day one
(11 May), are expected to cross threshold on day two (12 May) and are
likely to cross threshold on day three (13 May).

III.  Event probabilities 11 May-13 May
Class M    95/95/95
Class X    75/75/75
Proton     99/75/60
PCAF       yellow

IV.  Penticton 10.7 cm Flux
Observed           10 May 223
Predicted   11 May-13 May 225/220/220
90 Day Mean        10 May 164

V.  Geomagnetic A Indices
Observed Afr/Ap 09 May  007/005
Estimated Afr/Ap 10 May  085/097
Predicted Afr/Ap 11 May-13 May  064/090-020/030-015/020

VI.  Geomagnetic Activity Probabilities 11 May-13 May
A.  Middle Latitudes
Active                05/25/35
Minor Storm           40/40/20
Major-severe storm    55/25/05
B.  High Latitudes
Active                01/05/10
Minor Storm           05/15/25
Major-severe storm    95/79/55