Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 December 2019

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 352 Issued at 2200Z on 19 Dec 2019

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: 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 (19 Dec, 20 Dec, 21 Dec).

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 578 km/s at 18/1929Z. Total IMF reached 12 nT at 18/1025Z. The maximum southward component of Bz reached -10 nT at 18/1029Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (19 Dec) and quiet to unsettled levels on days two and three (20 Dec, 21 Dec).

III. Event probabilities 19 Dec-21 Dec
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 18 Dec 070
Predicted 19 Dec-21 Dec 070/070/070
90 Day Mean 18 Dec 069

V. Geomagnetic A Indices
Observed Afr/Ap 17 Dec 002/002
Estimated Afr/Ap 18 Dec 010/012
Predicted Afr/Ap 19 Dec-21 Dec 010/010-008/008-008/008

VI. Geomagnetic Activity Probabilities 19 Dec-21 Dec
A. Middle Latitudes
Active 30/20/20
Minor Storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 30/30/30
Major-severe storm 35/25/25