Viewing archive of Tuesday, 18 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 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 199 Issued at 2200Z on 18 Jul 2017IA. 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 M | 05% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 05% | 01% | 01% |
| PCAF | green | ||
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 | |||
|---|---|---|---|
| Active | 20% | 20% | 30% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 25% | 25% | 25% |
| Major-severe storm | 30% | 30% | 40% |
All times in UTC
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