Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 February 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 49 Issued at 2200Z on 18 Feb 2016

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C7 event observed at 18/0158Z from Region 2497 (N13, L=091). There are currently 3 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (19 Feb, 20 Feb, 21 Feb).

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at unsettled to major storm levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 723 km/s at 18/0538Z. Total IMF reached 8 nT at 17/2156Z. The maximum southward component of Bz reached -8 nT at 17/2144Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 13229 pfu.

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

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

IV. Penticton 10.7 cm Flux
Observed 18 Feb 095
Predicted 19 Feb-21 Feb 095/095/100
90 Day Mean 18 Feb 109

V. Geomagnetic A Indices
Observed Afr/Ap 17 Feb 021/031
Estimated Afr/Ap 18 Feb 024/032
Predicted Afr/Ap 19 Feb-21 Feb 015/020-011/012-007/008

VI. Geomagnetic Activity Probabilities 19 Feb-21 Feb
A. Middle Latitudes
Active 40/25/20
Minor Storm 20/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 10/15/20
Minor Storm 25/30/25
Major-severe storm 50/30/25