Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 February 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 52 Issued at 2200Z on 21 Feb 2017

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at very low levels for the past 24 hours. 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 (22 Feb, 23 Feb, 24 Feb).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 486 km/s at 20/2149Z. Total IMF reached 6 nT at 21/2049Z. The maximum southward component of Bz reached -4 nT at 21/0325Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1109 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and three (22 Feb, 24 Feb) and unsettled to minor storm levels on day two (23 Feb).

III.  Event probabilities 22 Feb-24 Feb
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Feb 083
Predicted   22 Feb-24 Feb 083/083/083
90 Day Mean        21 Feb 077

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Feb  008/006
Estimated Afr/Ap 21 Feb  005/007
Predicted Afr/Ap 22 Feb-24 Feb  012/015-016/020-013/014

VI.  Geomagnetic Activity Probabilities 22 Feb-24 Feb
A.  Middle Latitudes
Active                30/40/30
Minor Storm           15/25/15
Major-severe storm    01/05/01
B.  High Latitudes
Active                15/10/10
Minor Storm           30/25/25
Major-severe storm    40/60/45