Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 February 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 54 Issued at 2200Z on 23 Feb 2017

IA.  Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: 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 23/2053Z from Region 2638 (N18E20). There are currently 1 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 (24 Feb, 25 Feb, 26 Feb).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 650 km/s at 23/2048Z. Total IMF reached 12 nT at 23/1556Z. The maximum southward component of Bz reached -8 nT at 23/1931Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 642 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (24 Feb), quiet to active levels on day two (25 Feb) and quiet to unsettled levels on day three (26 Feb).

III.  Event probabilities 24 Feb-26 Feb
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           23 Feb 083
Predicted   24 Feb-26 Feb 083/083/083
90 Day Mean        23 Feb 077

V.  Geomagnetic A Indices
Observed Afr/Ap 22 Feb  008/010
Estimated Afr/Ap 23 Feb  011/014
Predicted Afr/Ap 24 Feb-26 Feb  014/018-011/012-008/008

VI.  Geomagnetic Activity Probabilities 24 Feb-26 Feb
A.  Middle Latitudes
Active                35/25/15
Minor Storm           20/10/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                10/15/15
Minor Storm           20/30/25
Major-severe storm    50/40/20