Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 April 2019

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 113 Issued at 2200Z on 23 Apr 2019

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 Apr, 25 Apr, 26 Apr).

IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 395 km/s at 23/0624Z. Total IMF reached 10 nT at 23/2013Z. The maximum southward component of Bz reached -9 nT at 23/1847Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 268 pfu.

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

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

IV.  Penticton 10.7 cm Flux
Observed           23 Apr 069
Predicted   24 Apr-26 Apr 069/069/069
90 Day Mean        23 Apr 072

V.  Geomagnetic A Indices
Observed Afr/Ap 22 Apr  004/004
Estimated Afr/Ap 23 Apr  004/006
Predicted Afr/Ap 24 Apr-26 Apr  007/008-012/015-009/010

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