Issued: 2013 Dec 17 1229 UTC
Eruptive (C-class flares expected, probability >=50%)
Quiet (A<20 and K<4)
Quiet
| 10cm flux | Ap | |
|---|---|---|
| 17 Dec 2013 | 152 | 006 |
| 18 Dec 2013 | 150 | 005 |
| 19 Dec 2013 | 150 | 011 |
The strongest solar flare was a C3.1 long-duration flare peaking on December 16 at 21h33 UTC originating from new active region NOAA AR 1927, located at the west limb. The flare was associated with a CME, observed in LASCO/C2 (first measurement on December 16 at 21h27 UTC) and STEREO A coronagraphic data (at 21h39 UTC). The CME is travelling to the west with an estimated speed of 650 km/s (estimated via Stereo CAT), with possible arrival of a glancing blow late December 19 (UTC time). The probability for C-flares is around 70%, M-flares around 30%, with NOAA ARs 1917 and 1927 as main source candidates. The chances for an X-flare are low. The proton flux measured by GOES, is below threshold levels. We are currently inside a slow solar wind stream with a solar wind speed of 400 km/s, as observed by ACE. The interplanetary magnetic field currently is weak with a maximum magnitude of 5 nT. Geomagnetic conditions are quiet (K<3) to unsettled (K=3) and are expected to remain so for the next 48 hours.
Today's estimated international sunspot number (ISN): 088, based on 07 stations.
| Wolf number Catania | /// |
| 10cm solar flux | 154 |
| AK Chambon La Forêt | 009 |
| AK Wingst | 006 |
| Estimated Ap | 006 |
| Estimated international sunspot number | 080 - Based on 18 stations |
| Day | Begin | Max | End | Loc | Strength | OP | 10cm | Catania/NOAA | Radio burst types | |
|---|---|---|---|---|---|---|---|---|---|---|
| None | ||||||||||
Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive
All times in UTC
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