Viewing archive of Tuesday, 28 March 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Mar 28 1234 UTC

SIDC Forecast

Valid from 1230 UTC, 28 Mar 2017 until 30 Mar 2017
Solar flares

C-class flares expected, (probability >=50%)

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

10cm fluxAp
28 Mar 2017085030
29 Mar 2017087006
30 Mar 2017083009

Bulletin

Over the past 24 hours solar activity has increased. There have been twenty six flares in total originated at two NOAA active regions NOAA AR 2644 (McIntosh:Dai; Mag.Type:Betta-Gamma) and NOAA AR 2645 (McIntosh:Gso; Mag.Type:Betta). Among them five C-class flares have been observed over the past 24 hours originated by both mentioned above ARs. The biggest flare C5.1 (NOAA AR 2644) peaked yesterday (27-Mar-2017) at 18.20 UT; the biggest flare C1.1 produced by NOAA AR 2644 peaked today (28-Mar-2017) at 00:27 UT. Two narrow CME have been detected by Cactus over the past 24 hours, they will not affect Earth environment. Solar protons have remained at background levels over the past 24 hours. Solar X-Ray background level is expected to grow more over the next 24 hours with a significant probability of C-class flares. M-class flares are also not excluded. Over the past 24 hours, solar wind speed measured by DSCOVR increased from about 550 km/s to 770 km/s (08:00 UT, 28-Mar-2017). The magnitude of the Interplanetary Magnetic Field (IMF) has a tendency to decrease (from about 5 nT to 4.5 nT, at 12:30 UT). Bz variations also strongly decreased (varying mostly between -3 nT and +3nT). The geomagnetic field reached major storm levels (Kp=6) during 18:00-21:00 UT time interval yesterday (27-Mar-2017), later 9 hours minor storming period has been observed (Kp=5) till 06:00 UT today (28-Mar-2017). Actual values of Kp are 3 (06:00 -09:00 UT) and 4 (09:00-12:00 UT). Values of local K Dourbes index are also decreasing from 6 to 3. Solar wind speed is expected to remain at high levels due to the coronal hole high speed stream effects for the next two days. However due to the low variations of the interplanetary magnetic field the geomagnetic environment will stay most probably at the active conditions (Kp=4) teh next two days. Minor storming isolated episodes (Kp=5) are possible.

Today's estimated international sunspot number (ISN): 056, based on 26 stations.

Solar indices for 27 Mar 2017

Wolf number Catania052
10cm solar flux083
AK Chambon La Forêt056
AK Wingst048
Estimated Ap051
Estimated international sunspot number048 - Based on 32 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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