SIDC Ursigram
3-day-forecast of solar and geomagnetic activity.| Source | SIDC (RWC-Belgium) |
| Frequency | Daily |
| Format | Encoded data (ISES) |
| Mail header | SIDC Ursigram |
| SIDC code | meu |
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Latest issue
:Issued: 2026 Aug 12 1231 UTC :Product: documentation at http://www.sidc.be/products/meu #--------------------------------------------------------------------# # DAILY BULLETIN ON SOLAR AND GEOMAGNETIC ACTIVITY from the SIDC # # (RWC Belgium) # #--------------------------------------------------------------------# SIDC URSIGRAM 60812 SIDC SOLAR BULLETIN 12 Aug 2026, 1230UT SIDC FORECAST SOLAR FLARES : C-class flares expected, (probability >=50%) GEOMAGNETISM : Quiet (A<20 and K<4) SOLAR PROTONS : Quiet PREDICTIONS FOR 12 Aug 2026 10CM FLUX: 098 / AP: 010 PREDICTIONS FOR 13 Aug 2026 10CM FLUX: 104 / AP: 006 PREDICTIONS FOR 14 Aug 2026 10CM FLUX: 106 / AP: 018 Solar Active Regions and flaring: Solar flaring activity was low over the past 24 hours, with only four C-class flares identified. The newly-numbered SIDC Sunspot Group (SG) 940 (NOAA Active Region [AR] 4507, Beta magnetic configuration) and SIDC SG 941 (NOAA AR 4508, Alpha magnetic configuration) produced two C-class flares each. The brightest flare of the past 24 hours was SIDC flare 8348, a C2 emitted from SIDC SG 940 and peaked on 22 Aug at 23:04 UTC. More C-class flaring activity is expected in the next 24 hours. Coronal mass ejections: No Earth-directed Coronal Mass Ejections (CME) were observed in the last 24 hours. Coronal holes: SIDC Coronal Hole (CH) 174 is a northern, middle-latitude, elongated, irregular, positive polarity structure. It started crossing the solar central meridian on 10 Aug, but it was considered too weak to cause a geo-effective High Speed Stream (HSS). However, the structure has intensify since and it is now likely that it is associated with a HSS capable of reaching the Earth. As SIDC CH 174 it still crossing the central meridian, the said HSS is considered to be Earth-directed and to arrive at Earth on 14 Aug. Solar wind: The glancing blow that arrived on 11 Aug at 10:34 UTC has now subsided and the Solar Wind (SW) conditions are now closer to a typical slow SW regime. The SW speed marginally increased from 420 to 460 km/s, the interplanetary magnetic field (B) ranged dropped to 5 nT, and its North- South component (Bz) varies between -5 and 3 nT. Similar conditions are expected to register in the next 24 hours. Geomagnetism: The geomagnetic conditions of the past 24 hours ranged between quiet and unsettled levels both globally and locally (NOAA Kp 1+ to 3+ and K BEL 2 to 3). Similar conditions are expected in the next 24 hours. Proton flux levels: The greater than 10 MeV proton flux, as measured by the GOES-19 satellite, was at nominal levels over the past 24 hours and is likely to remain so in the next 24 hours. Electron fluxes at GEO: The greater than 2 MeV electron flux, as measured by GOES 19, was below the 1000 pfu alert threshold for past 24 hours. It is expected to remain at the same levels in the next 24 hours. The electron fluence was at normal levels in the past 24 hours and it is expected to remain at the same levels in the next 24 hours. TODAY'S ESTIMATED ISN : 074, BASED ON 23 STATIONS. SOLAR INDICES FOR 11 Aug 2026 WOLF NUMBER CATANIA : /// 10CM SOLAR FLUX : 096 AK CHAMBON LA FORET : 016 AK WINGST : 011 ESTIMATED AP : 009 ESTIMATED ISN : 044, BASED ON 29 STATIONS. NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES NONE END BT #--------------------------------------------------------------------# # Solar Influences Data analysis Center - RWC Belgium # # Royal Observatory of Belgium # # # # Website http://www.sidc.be. # # E-mail sidc-support@oma.be # # To unsubscribe http://www.sidc.be/registration/unsub.php # # # # Legal notices: # # - Intellectual Property Rights: # # http://www.astro.oma.be/common/internet/en/data-policy-en.pdf # # - Liability Disclaimer: # # http://www.astro.oma.be/common/internet/en/disclaimer-en.pdf # # - Use and processing of your personal information: # # http://www.astro.oma.be/common/internet/en/privacy-policy-en.pdf # #--------------------------------------------------------------------#
Details
The SIDC ursigram starts with the code SIDC URSIGRAM YMMDD, whereY is the last digit of the year number,
MM is the number of the month,
DD is the day of the month.
A forecast is given on:
the global flare probability,
geomagnetic disturbances,
solar proton events.
PREDICTIONS FOR "today" : 10CM FLUX: xxx / AP: xxx
PREDICTIONS FOR "today+1": 10CM FLUX: xxx / AP: xxx
PREDICTIONS FOR "today+2": 10CM FLUX: xxx / AP: xxx
COMMENT
ESTIMATED ISN : xxx, based on xx stations.
where ISN stands for International Sunspot Number.
OBSERVED SOLAR INDICES FOR THE DAY BEFORE
SUNSPOT INDEX : xxx, the Wolf number observed by Catania
10CM SOLAR FLUX : xxx,
AK CHAMBON LA FORET : xxx,
AK WINGST : xxx,
ESTIMATED AP : xxx,
ESTIMATED ISN : xxx, based on xx stations.
NOTICEABLE EVENTS SUMMARY
DAY BEGIN MAX END LOC XRAY OP 10CM TYPE Catania NOAA NOTE
DAY gives the day-of-the-month.
BEGIN, MAX and END give the UT time of the different phases of the X-ray output of the event.
LOC gives the location of the event in heliographic coordinates.
XRAY gives the GOES X-ray class of the event.
OP lists the optical flare class.
10cm gives the 10.7 cm radioflux output of the event.
TYPE specifies the type of radiobursts observed.
Catania gives the Catania sunspot group number where the event happened.
NOAA is the corresponding NOAA active region number.
NOTE is the header of any other type of information, e.g. if a CME was observed associated with the event.
Check the ISES code book for information on ISES codes.