Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 February 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 35 Issued at 2200Z on 04 Feb 2018

IA.  Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: 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 04/2024Z from Region 2699 (S04E74). There are currently 1 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (05 Feb, 06 Feb, 07 Feb).

IIA.  Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 389 km/s at 04/2028Z. Total IMF reached 9 nT at 04/1900Z. The maximum southward component of Bz reached -5 nT at 04/1709Z.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (05 Feb) and quiet levels on days two and three (06 Feb, 07 Feb).

III.  Event probabilities 05 Feb-07 Feb
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           04 Feb 073
Predicted   05 Feb-07 Feb 072/072/072
90 Day Mean        04 Feb 071

V.  Geomagnetic A Indices
Observed Afr/Ap 03 Feb  002/003
Estimated Afr/Ap 04 Feb  007/010
Predicted Afr/Ap 05 Feb-07 Feb  008/008-006/005-006/005

VI.  Geomagnetic Activity Probabilities 05 Feb-07 Feb
A.  Middle Latitudes
Active                20/05/10
Minor Storm           05/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/15/15
Minor Storm           25/20/20
Major-severe storm    25/15/15