Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 May 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 124 Issued at 2200Z on 04 May 2021

IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: 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 (05 May, 06 May, 07 May).

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 499 km/s at 03/2351Z. Total IMF reached 6 nT at 04/0409Z. The maximum southward component of Bz reached -4 nT at 04/0002Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 239 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (05 May, 06 May, 07 May).

III. Event probabilities 05 May-07 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 04 May 070
Predicted 05 May-07 May 072/072/072
90 Day Mean 04 May 076

V. Geomagnetic A Indices
Observed Afr/Ap 03 May 006/005
Estimated Afr/Ap 04 May 005/006
Predicted Afr/Ap 05 May-07 May 006/005-006/005-006/005

VI. Geomagnetic Activity Probabilities 05 May-07 May
A. Middle Latitudes
Active 15/10/10
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/20
Minor Storm 20/20/20
Major-severe storm 20/10/10