Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 26 April 2019

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 116 Issued at 2200Z on 26 Apr 2019

IA. Analysis of Solar Active Regions and Activity from 25/2100Z to 26/2100Z: 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 (27 Apr, 28 Apr, 29 Apr).

IIA. Geophysical Activity Summary 25/2100Z to 26/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 427 km/s at 26/0006Z. Total IMF reached 5 nT at 26/1915Z. The maximum southward component of Bz reached -4 nT at 26/1915Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 109 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one, two, and three (27 Apr, 28 Apr, 29 Apr).

III. Event probabilities 27 Apr-29 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 26 Apr 067
Predicted 27 Apr-29 Apr 067/067/067
90 Day Mean 26 Apr 072

V. Geomagnetic A Indices
Observed Afr/Ap 25 Apr 004/004
Estimated Afr/Ap 26 Apr 003/004
Predicted Afr/Ap 27 Apr-29 Apr 008/008-009/008-008/008

VI. Geomagnetic Activity Probabilities 27 Apr-29 Apr
A. Middle Latitudes
Active 20/25/25
Minor Storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/20
Minor Storm 25/30/30
Major-severe storm 30/25/25