Viewing archive of Tuesday, 18 July 2023

Solar activity report

Report of Solar-Geophysical Activity 2023 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 2023

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

Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a M5 event observed at 18/0006Z from Region 3363 (S21W86). There are currently 8 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate with a slight chance for an X-class flare on day one (19 Jul) and expected to be low with a chance for M-class flares and a slight chance for an X-class flare 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 minor storm levels for the past 24 hours. Solar wind speed reached a peak of 556 km/s at 17/2204Z. Total IMF reached 7 nT at 17/2134Z. The maximum southward component of Bz reached -6 nT at 18/0121Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 619 pfu at 18/0615Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 936 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to active levels on days one and three (19 Jul, 21 Jul) and quiet to minor storm levels on day two (20 Jul). Protons are expected to cross threshold on day one (19 Jul), are likely to cross threshold on day two (20 Jul) and have a chance of crossing threshold on day three (21 Jul).
III. Event Probabilities 19 Jul to 21 Jul
Class M55%45%45%
Class X20%20%15%
IV. Penticton 10.7 cm Flux
  Observed       18 Jul 219
  Predicted   19 Jul-21 Jul 210/210/210
  90 Day Mean        18 Jul 161

V. Geomagnetic A Indices
  Observed Afr/Ap 17 Jul  019/023
  Estimated     Afr/Ap 18 Jul  016/021
  Predicted    Afr/Ap 19 Jul-21 Jul  010/012-018/028-015/020

VI. Geomagnetic Activity Probabilities 19 Jul to 21 Jul
A. Middle Latitudes
Minor storm10%30%20%
Major-severe storm01%15%05%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm20%50%40%

All times in UTC

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