Viewing archive of Thursday, 16 May 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 May 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 136 Issued at 2200Z on 16 May 2013IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C4 event observed at
16/1924Z from Region 1748 (N12E36). There are currently 10 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be high with
a chance for X-class flares on days one, two, and three (17 May, 18 May,
19 May).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
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
450 km/s at 15/2326Z. Total IMF reached 7 nT at 15/2115Z. The maximum
southward component of Bz reached -6 nT at 16/0139Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 32 pfu at
16/0410Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 117 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (17 May) and quiet to
unsettled levels on days two and three (18 May, 19 May). Protons are
expected to cross threshold on day one (17 May), are expected to cross
threshold on day two (18 May) and are expected to cross threshold on day
three (19 May).
III. Event Probabilities 17 May to 19 May
| Class M | 75% | 75% | 75% |
| Class X | 50% | 50% | 50% |
| Proton | 99% | 95% | 90% |
| PCAF | yellow | ||
IV. Penticton 10.7 cm Flux
Observed 16 May 145 Predicted 17 May-19 May 145/145/140 90 Day Mean 16 May 120
V. Geomagnetic A Indices
Observed Afr/Ap 15 May 010/008 Estimated Afr/Ap 16 May 010/011 Predicted Afr/Ap 17 May-19 May 011/015-008/008-007/008
VI. Geomagnetic Activity Probabilities 17 May to 19 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 15% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 25% | 25% |
| Major-severe storm | 40% | 25% | 25% |
All times in UTC
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