Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 17 July 2017
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 198 Issued at 2200Z on 17 Jul 2017
IA.
Analysis of Solar Active Regions and Activity from 16/2100Z to
17/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
17/0328Z from Region 2665 (S06W86). There are currently 1 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar
activity is likely to be low with a slight chance for an M-class flare
on day one (18 Jul) and expected to be very low with a chance for a
C-class flares on day two (19 Jul) and expected to be very low with a
slight chance for a C-class flare on day three (20 Jul).
IIA.
Geophysical Activity Summary 16/2100Z to 17/2100Z: The geomagnetic field
has been at quiet to major storm levels for the past 24 hours. Solar
wind speeds averaged around 540 km/s. Total IMF reached 14 nT at
16/2211Z. The maximum southward component of Bz reached -10 nT at
17/1359Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 12226 pfu.
IIB. Geophysical Activity Forecast:
The geomagnetic field is expected to be at quiet to active levels on day
one (18 Jul) and quiet to unsettled levels on days two and three (19
Jul, 20 Jul). Protons greater than 10 Mev have a slight chance of
crossing threshold on day one (18 Jul).
III. Event probabilities 18 Jul-20 Jul
Class M 20/05/01
Class X 05/01/01
Proton 20/05/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 17 Jul 086
Predicted 18 Jul-20 Jul 085/075/075
90 Day Mean 17 Jul 077
V. Geomagnetic A Indices
Observed Afr/Ap 16 Jul 029/042
Estimated Afr/Ap 17 Jul 025/037
Predicted Afr/Ap 18 Jul-20 Jul 011/012-008/008-007/008
VI. Geomagnetic Activity Probabilities 18 Jul-20 Jul
A. Middle Latitudes
Active 35/20/20
Minor Storm 15/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 10/15/15
Minor Storm 30/25/25
Major-severe storm 50/30/30
