Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 22 May 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 142 Issued at 2200Z on 22 May 2017

IA.  Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 4 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 (23 May, 24 May, 25 May).

IIA.  Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 619 km/s at 22/1940Z. Total IMF reached 6 nT at 22/0736Z. The maximum southward component of Bz reached -5 nT at 22/1634Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 26098 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (23 May, 24 May) and quiet levels on day three (25 May).

III.  Event probabilities 23 May-25 May
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           22 May 074
Predicted   23 May-25 May 075/075/075
90 Day Mean        22 May 077

V.  Geomagnetic A Indices
Observed Afr/Ap 21 May  010/009
Estimated Afr/Ap 22 May  007/009
Predicted Afr/Ap 23 May-25 May  007/008-007/008-005/005

VI.  Geomagnetic Activity Probabilities 23 May-25 May
A.  Middle Latitudes
Active                15/05/10
Minor Storm           05/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/15/15
Major-severe storm    20/05/10