Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 3 April 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 93 Issued at 2200Z on 03 Apr 2017

IA.  Analysis of Solar Active Regions and Activity from 02/2100Z to 03/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a M5 event observed at 03/1429Z from Region 2644 (N13W79). There are currently 4 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be moderate with a chance for X-class flares on day one (04 Apr) and expected to be low with a chance for M-class flares and a slight chance for an X-class flare on day two (05 Apr) and likely to be low with a chance for M-class flares and a slight chance for an X-class flare on day three (06 Apr).

IIA.  Geophysical Activity Summary 02/2100Z to 03/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 466 km/s at 02/2105Z. Total IMF reached 6 nT at 03/0534Z. The maximum southward component of Bz reached -2 nT at 03/0841Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 53552 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (04 Apr) and quiet to unsettled levels on days two and three (05 Apr, 06 Apr). Protons have a chance of crossing threshold on days one and two (04 Apr, 05 Apr) and have a slight chance of crossing threshold on day three (06 Apr).

III.  Event probabilities 04 Apr-06 Apr
Class M    70/50/35
Class X    25/15/10
Proton     25/25/15
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           03 Apr 108
Predicted   04 Apr-06 Apr 108/102/096
90 Day Mean        03 Apr 077

V.  Geomagnetic A Indices
Observed Afr/Ap 02 Apr  006/006
Estimated Afr/Ap 03 Apr  005/005
Predicted Afr/Ap 04 Apr-06 Apr  005/005-006/006-007/008

VI.  Geomagnetic Activity Probabilities 04 Apr-06 Apr
A.  Middle Latitudes
Active                10/10/10
Minor Storm           01/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           15/15/20
Major-severe storm    10/15/20