Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 May 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 140 Issued at 2200Z on 20 May 2018

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: 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 (21 May, 22 May, 23 May).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 444 km/s at 20/1533Z. Total IMF reached 5 nT at 20/0220Z. The maximum southward component of Bz reached -4 nT at 20/0510Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 626 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (21 May, 22 May) and quiet to active levels on day three (23 May).

III.  Event probabilities 21 May-23 May
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 May 069
Predicted   21 May-23 May 069/069/069
90 Day Mean        20 May 069

V.  Geomagnetic A Indices
Observed Afr/Ap 19 May  003/003
Estimated Afr/Ap 20 May  004/004
Predicted Afr/Ap 21 May-23 May  006/005-006/005-011/015

VI.  Geomagnetic Activity Probabilities 21 May-23 May
A.  Middle Latitudes
Active                10/10/30
Minor Storm           01/01/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           15/15/30
Major-severe storm    10/10/40