Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 30 December 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 364 Issued at 2200Z on 30 Dec 2015

IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 30/1905Z from Region 2473 (S21W47). There are currently 2 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (31 Dec, 01 Jan, 02 Jan).

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 398 km/s at 30/0038Z. Total IMF reached 5 nT at 30/1819Z. The maximum southward component of Bz reached -4 nT at 29/2106Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1656 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to severe storm levels on day one (31 Dec), unsettled to minor storm levels on day two (01 Jan) and unsettled to active levels on day three (02 Jan). Protons have a slight chance of crossing threshold on days one, two, and three (31 Dec, 01 Jan, 02 Jan).

III. Event probabilities 31 Dec-02 Jan
Class M 40/30/25
Class X 05/01/01
Proton 15/15/15
PCAF green

IV. Penticton 10.7 cm Flux
Observed 30 Dec 102
Predicted 31 Dec-02 Jan 100/105/105
90 Day Mean 30 Dec 109

V. Geomagnetic A Indices
Observed Afr/Ap 29 Dec 004/004
Estimated Afr/Ap 30 Dec 008/017
Predicted Afr/Ap 31 Dec-02 Jan 028/046-020/024-015/018

VI. Geomagnetic Activity Probabilities 31 Dec-02 Jan
A. Middle Latitudes
Active 15/45/40
Minor Storm 35/25/20
Major-severe storm 50/05/05
B. High Latitudes
Active 01/05/10
Minor Storm 10/25/25
Major-severe storm 90/65/60