Viewing archive of Thursday, 18 July 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 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 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 C2 event observed at
18/1823Z from Region 1800 (S10E63). There are currently 7 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 days one, two, and three (19 Jul,
20 Jul, 21 Jul).
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, as measured by the ACE spacecraft, reached a peak speed of
560 km/s at 18/1732Z. Total IMF reached 18 nT at 18/1345Z. The maximum
southward component of Bz reached -11 nT at 18/1300Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 2285 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to minor storm levels on days one and two (19 Jul, 20
Jul) and unsettled to active levels on day three (21 Jul).
III. Event Probabilities 19 Jul to 21 Jul
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Jul 115 Predicted 19 Jul-21 Jul 120/125/125 90 Day Mean 18 Jul 121
V. Geomagnetic A Indices
Observed Afr/Ap 17 Jul 005/004 Estimated Afr/Ap 18 Jul 010/015 Predicted Afr/Ap 19 Jul-21 Jul 013/020-013/020-011/015
VI. Geomagnetic Activity Probabilities 19 Jul to 21 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 45% | 45% | 35% |
| Minor storm | 20% | 20% | 15% |
| Major-severe storm | 05% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 25% | 25% | 30% |
| Major-severe storm | 65% | 65% | 50% |
All times in UTC
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