Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 209 Issued at 2200Z on 28 Jul 2023
IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M4 event observed at 28/1558Z from Region 3376 (N23, L=228). There are currently 10 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 (29 Jul, 30 Jul, 31 Jul).
IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 453 km/s at 28/0104Z. Total IMF reached 7 nT at 28/1420Z. The maximum southward component of Bz reached -6 nT at 28/1438Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 5 pfu at 28/2045Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 753 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and three (29 Jul, 31 Jul) and quiet to active levels on day two (30 Jul). Protons greater than 10 Mev are expected to cross threshold on day one (29 Jul) and have a slight chance of crossing threshold on day two (30 Jul).
III. Event probabilities 29 Jul-31 Jul
Class M 40/40/40
Class X 05/05/05
Proton 90/15/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 28 Jul 168
Predicted 29 Jul-31 Jul 165/162/158
90 Day Mean 28 Jul 164
V. Geomagnetic A Indices
Observed Afr/Ap 27 Jul 007/006
Estimated Afr/Ap 28 Jul 005/006
Predicted Afr/Ap 29 Jul-31 Jul 008/008-011/015-008/010
VI. Geomagnetic Activity Probabilities 29 Jul-31 Jul
A. Middle Latitudes
Active 15/30/20
Minor Storm 05/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/15
Minor Storm 20/25/20
Major-severe storm 20/20/20
space weather
