Viewing archive of Monday, 17 July 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 Jul 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 198 Issued at 2200Z on 17 Jul 2017IA. 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 to 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 to 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% |
All times in UTC
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