Viewing archive of Saturday, 9 September 2017

Solar activity report

Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2017 Sep 09 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 252 Issued at 2200Z on 09 Sep 2017

IA. Analysis of Solar Active Regions and Activity from 08-2100Z to 09-2100Z

Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M3 event observed at 09/1104Z from Region 2673 (S09W83). There are currently 3 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate with a chance for X-class flares on day one (10 Sep) and expected to be low with a chance for M-class flares on day two (11 Sep) and expected to be very low with a slight chance for a C-class flare on day three (12 Sep).
IIA. Geophysical Activity Summary 08-2100Z to 09-2100Z
The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 847 km/s at 08/2150Z. Total IMF reached 6 nT at 08/2201Z. The maximum southward component of Bz reached -3 nT at 08/2105Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 14 pfu at 08/2100Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 6358 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on days one and three (10 Sep, 12 Sep) and quiet to unsettled levels on day two (11 Sep). Protons greater than 10 Mev have a chance of crossing threshold on day one (10 Sep) and have a slight chance of crossing threshold on day two (11 Sep).
III. Event Probabilities 10 Sep to 12 Sep
Class M70%25%01%
Class X35%05%01%
Proton25%15%05%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       09 Sep 107
  Predicted   10 Sep-12 Sep 095/085/083
  90 Day Mean        09 Sep 081

V. Geomagnetic A Indices
  Observed Afr/Ap 08 Sep  050/117
  Estimated     Afr/Ap 09 Sep  007/007
  Predicted    Afr/Ap 10 Sep-12 Sep  007/008-007/008-006/005

VI. Geomagnetic Activity Probabilities 10 Sep to 12 Sep
A. Middle Latitudes
Active20%15%10%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active15%15%15%
Minor storm20%20%20%
Major-severe storm20%20%15%

All times in UTC

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Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future

Oulu, Rovaniemi, Sodankylä, Utsjoki
Reykjavik
Kirkenes, Tromsø, Trondheim
Murmansk
Kiruna, Luleå
The Disturbance Storm Time index predicts moderate storm conditions right now (-50nT)
A transequatorial coronal hole was detected in an earth-facing position on Monday, 24 March 2025

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Coronal hole faces Earth

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