Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 201 Issued at 2200Z on 20 Jul 2023
IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C9 event observed at 20/1949Z from Region 3373 (N08W15). There are currently 7 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 (21 Jul, 22 Jul, 23 Jul).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 487 km/s at 20/1750Z. Total IMF reached 12 nT at 20/1627Z. The maximum southward component of Bz reached -10 nT at 20/1635Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 14 pfu at 19/2135Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1856 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (21 Jul), quiet to active levels on day two (22 Jul) and quiet to unsettled levels on day three (23 Jul). Protons greater than 10 Mev have a chance of crossing threshold on day one (21 Jul) and have a slight chance of crossing threshold on day two (22 Jul).
III. Event probabilities 21 Jul-23 Jul
Class M 45/45/45
Class X 05/05/05
Proton 25/15/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 Jul 184
Predicted 21 Jul-23 Jul 185/185/185
90 Day Mean 20 Jul 162
V. Geomagnetic A Indices
Observed Afr/Ap 19 Jul 007/004
Estimated Afr/Ap 20 Jul 010/014
Predicted Afr/Ap 21 Jul-23 Jul 015/020-011/012-008/008
VI. Geomagnetic Activity Probabilities 21 Jul-23 Jul
A. Middle Latitudes
Active 35/25/20
Minor Storm 25/10/05
Major-severe storm 10/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/20/20
Major-severe storm 45/20/15
space weather
