Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 29 July 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 210 Issued at 2200Z on 29 Jul 2021

IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (30 Jul, 31 Jul, 01 Aug).

IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 574 km/s at 29/0345Z. Total IMF reached 6 nT at 29/1901Z. The maximum southward component of Bz reached -4 nT at 29/0753Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 383 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (30 Jul, 31 Jul and quiet to active levels on day three (01 Aug).

III. Event probabilities 30 Jul-01 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 29 Jul 076
Predicted 30 Jul-01 Aug 076/076/074
90 Day Mean 29 Jul 079

V. Geomagnetic A Indices
Observed Afr/Ap 28 Jul 013/013
Estimated Afr/Ap 29 Jul 008/008
Predicted Afr/Ap 30 Jul-01 Aug 008/008-008/010-010/012

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