Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 August 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 236 Issued at 2200Z on 24 Aug 2018

IA.  Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (25 Aug, 26 Aug, 27 Aug).

IIA.  Geophysical Activity Summary 23/2100Z to 24/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 405 km/s at 23/2106Z. Total IMF reached 7 nT at 24/1252Z. The maximum southward component of Bz reached -6 nT at 24/1116Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3701 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (25 Aug), quiet to unsettled levels on day two (26 Aug) and quiet levels on day three (27 Aug).

III.  Event probabilities 25 Aug-27 Aug

Class M    01/01/01

Class X    01/01/01

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           24 Aug 072

Predicted   25 Aug-27 Aug 072/072/072

90 Day Mean        24 Aug 071

V.  Geomagnetic A Indices

Observed Afr/Ap 23 Aug  005/004

Estimated Afr/Ap 24 Aug  006/008

Predicted Afr/Ap 25 Aug-27 Aug  010/012-008/008-006/005

VI.  Geomagnetic Activity Probabilities 25 Aug-27 Aug

A.  Middle Latitudes

Active                35/25/15

Minor Storm           15/10/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                10/15/15

Minor Storm           25/25/20

Major-severe storm    50/35/20