Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 September 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 266 Issued at 2200Z on 23 Sep 2018

IA.  Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low on days one, two, and three (24 Sep, 25 Sep, 26 Sep).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 555 km/s at 22/2146Z. Total IMF reached 10 nT at 23/1312Z. The maximum southward component of Bz reached -5 nT at 23/1442Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 8045 pfu.

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

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

IV.  Penticton 10.7 cm Flux
Observed           23 Sep 068
Predicted   24 Sep-26 Sep 068/068/068
90 Day Mean        23 Sep 069

V.  Geomagnetic A Indices
Observed Afr/Ap 22 Sep  020/021
Estimated Afr/Ap 23 Sep  012/015
Predicted Afr/Ap 24 Sep-26 Sep  012/015-009/010-007/008

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