Viewing archive of Thursday, 18 May 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 May 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 138 Issued at 2200Z on 18 May 2017IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 2 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a slight chance for a C-class flare on days one, two, and three (19
May, 20 May, 21 May).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 458 km/s at 17/2148Z. Total IMF reached 9
nT at 18/1717Z. The maximum southward component of Bz reached -6 nT at
18/0338Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 149 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at active to major storm levels on day one (19 May), active to
minor storm levels on day two (20 May) and quiet to active levels on day
three (21 May).
III. Event Probabilities 19 May to 21 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 May 072 Predicted 19 May-21 May 072/072/072 90 Day Mean 18 May 077
V. Geomagnetic A Indices
Observed Afr/Ap 17 May 009/009 Estimated Afr/Ap 18 May 013/018 Predicted Afr/Ap 19 May-21 May 031/045-024/030-016/020
VI. Geomagnetic Activity Probabilities 19 May to 21 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 40% | 20% |
| Minor storm | 35% | 20% | 05% |
| Major-severe storm | 15% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 15% |
| Major-severe storm | 20% | 15% | 10% |
All times in UTC
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