Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 May 2019

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 137 Issued at 2200Z on 17 May 2019

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 1 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 473 km/s at 17/0046Z. Total IMF reached 7 nT at 16/2136Z. The maximum southward component of Bz reached -4 nT at 16/2218Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 750 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (18 May, 19 May) and quiet to unsettled 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 072
Predicted   18 May-20 May 072/070/068
90 Day Mean        17 May 072

V.  Geomagnetic A Indices
Observed Afr/Ap 16 May  009/008
Estimated Afr/Ap 17 May  008/010
Predicted Afr/Ap 18 May-20 May  006/005-006/005-007/008

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