Viewing archive of Sunday, 18 August 2013
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 2013 Aug 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 230 Issued at 2200Z on 18 Aug 2013IA. 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 C1 event observed at
18/1131Z. There are currently 9 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (19 Aug, 20 Aug,
21 Aug).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 650 km/s at
17/2126Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 4650 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (19 Aug), quiet to active levels on day
two (20 Aug) and unsettled to active levels on day three (21 Aug).
Protons have a chance of crossing threshold on days one, two, and three
(19 Aug, 20 Aug, 21 Aug).
III. Event Probabilities 19 Aug to 21 Aug
| Class M | 25% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 25% | 25% | 25% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Aug 126 Predicted 19 Aug-21 Aug 130/125/120 90 Day Mean 18 Aug 113
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 009/008 Estimated Afr/Ap 18 Aug 006/006 Predicted Afr/Ap 19 Aug-21 Aug 006/005-010/018-018/025
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 45% |
| Minor storm | 01% | 05% | 15% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 10% |
| Minor storm | 35% | 35% | 35% |
| Major-severe storm | 25% | 30% | 55% |
All times in UTC
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