Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 May 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 137 Issued at 2200Z on 17 May 2018

IA.  Analysis of Solar Active Regions and Activity from 16/2100Z to 17/2100Z: 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 (18 May, 19 May, 20 May).

IIA.  Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 455 km/s at 17/1931Z. Total IMF reached 10 nT at 17/1019Z. The maximum southward component of Bz reached -8 nT at 17/1010Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 12809 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (18 May), quiet to unsettled levels on day two (19 May) and quiet levels on day three (20 May).

III.  Event probabilities 18 May-20 May
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           17 May 069
Predicted   18 May-20 May 069/069/069
90 Day Mean        17 May 069

V.  Geomagnetic A Indices
Observed Afr/Ap 16 May  003/003
Estimated Afr/Ap 17 May  012/014
Predicted Afr/Ap 18 May-20 May  010/012-007/008-006/005

VI.  Geomagnetic Activity Probabilities 18 May-20 May
A.  Middle Latitudes
Active                30/20/10
Minor Storm           10/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           25/25/15
Major-severe storm    40/25/10