Viewing archive of Tuesday, 18 July 2017

Solar activity report

Report of Solar-Geophysical Activity 2017 Jul 18 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 199 Issued at 2200Z on 18 Jul 2017

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

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 18/0040Z from old Region 2665 - now around the West limb. There are currently no numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low with a chance for a C-class flares on day one (19 Jul) and expected to be very low on days two and three (20 Jul, 21 Jul).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed averaged near 550 km/s. Total IMF reached 10 nT at 18/0357Z. The maximum southward component of Bz reached -8 nT at 18/0055Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 5531 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (19 Jul, 20 Jul) and quiet to active levels on day three (21 Jul).
III. Event Probabilities 19 Jul to 21 Jul
Class M05%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       18 Jul 078
  Predicted   19 Jul-21 Jul 075/075/075
  90 Day Mean        18 Jul 077

V. Geomagnetic A Indices
  Observed Afr/Ap 17 Jul  023/033
  Estimated     Afr/Ap 18 Jul  009/010
  Predicted    Afr/Ap 19 Jul-21 Jul  008/008-007/008-009/012

VI. Geomagnetic Activity Probabilities 19 Jul to 21 Jul
A. Middle Latitudes
Minor storm05%05%10%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm30%30%40%

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