Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 25 December 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 359 Issued at 2200Z on 25 Dec 2018

IA.  Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: 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 (26 Dec, 27 Dec, 28 Dec).

IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 370 km/s at 25/1940Z. Total IMF reached 6 nT at 25/0752Z. The maximum southward component of Bz reached -5 nT at 25/1206Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 260 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (26 Dec, 27 Dec) and quiet to unsettled levels on day three (28 Dec).

III.  Event probabilities 26 Dec-28 Dec
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           25 Dec 070
Predicted   26 Dec-28 Dec 070/070/070
90 Day Mean        25 Dec 070

V.  Geomagnetic A Indices
Observed Afr/Ap 24 Dec  003/001
Estimated Afr/Ap 25 Dec  004/004
Predicted Afr/Ap 26 Dec-28 Dec  006/005-005/005-007/008

VI.  Geomagnetic Activity Probabilities 26 Dec-28 Dec
A.  Middle Latitudes
Active                10/10/20
Minor Storm           01/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/25
Major-severe storm    10/20/30