:Issued: 2017 Apr 03 1230 UTC :Product: documentation at http://www.sidc.be/products/tot #--------------------------------------------------------------------# # DAILY BULLETIN ON SOLAR AND GEOMAGNETIC ACTIVITY from the SIDC # #--------------------------------------------------------------------# SIDC URSIGRAM 70403 SIDC SOLAR BULLETIN 03 Apr 2017, 1230UT SIDC FORECAST (valid from 1230UT, 03 Apr 2017 until 05 Apr 2017) SOLAR FLARES : M-class flares expected (probability >=50%) GEOMAGNETISM : Quiet (A<20 and K<4) SOLAR PROTONS : Warning condition (activity levels expected to increase, but no numeric forecast given) PREDICTIONS FOR 03 Apr 2017 10CM FLUX: 108 / AP: 003 PREDICTIONS FOR 04 Apr 2017 10CM FLUX: 103 / AP: 008 PREDICTIONS FOR 05 Apr 2017 10CM FLUX: 100 / AP: 005 COMMENT: Solar activity was at high levels during the period. Four M-class flares were recorded, the strongest being an M5.7 event peaking at 20:33UT. NOAA 2644 has developed a complex magnetic configuration and was the source of all important flaring. This region is approaching the west limb. NOAA 2645 was quiet, despite the important delta structure in its trailing portion. A long duration M2 flare peaking at 18:38UT affected the 20UT value of the 10.7cm radio flux. No earth-directed coronal mass ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10MeV proton flux was at nominal levels. Further M-class flaring is expected, with a chance on an X-class flare. As both NOAA 2644 and 2645 are in the western solar hemisphere, a major flare from any of these regions may drive the greater than 10MeV proton levels above event threshold. Solar wind speed declined from about 510 km/s to values around 420 km/s. Bz fluctuated between -3 nT and +2 nT. The interplanetary magnetic field was mostly directed towards the Sun, except for the first 3 and last 3 hours of the period (away from the Sun). There's a small chance that the particle stream from a weak positive coronal hole may affect the earth environment on 4 April. The geomagnetic field was at quiet to unsettled levels and is expected to remain so. TODAY'S ESTIMATED ISN : 102, BASED ON 20 STATIONS. 99999 SOLAR INDICES FOR 02 Apr 2017 WOLF NUMBER CATANIA : /// 10CM SOLAR FLUX : 112 AK CHAMBON LA FORET : 011 AK WINGST : 008 ESTIMATED AP : 008 ESTIMATED ISN : 084, BASED ON 36 STATIONS. NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES 02 1252 1300 1311 ////// M2.3 110 08/2644 02 1818 1838 1928 N16W68 M2.1 SF 08/2644 III/1 02 2026 2033 2038 ////// M5.7 08/2644 03 0056 0105 0112 N15W75 M1.2 SF 08/2644 END UMAGF 30503 70403 1004/ 02063 1/011 22123 32101 UMAGF 31523 70403 0000/ 02005 1/008 22222 33321 BT #--------------------------------------------------------------------# # Solar Influences Data analysis Center - RWC Belgium # # Royal Observatory of Belgium # # Fax : 32 (0) 2 373 0 224 # # Tel.: 32 (0) 2 373 0 491 # # # # For more information, see http://www.sidc.be. Please do not reply # # directly to this message, but send comments and suggestions to # # 'sidctech@oma.be'. If you are unable to use that address, use # # 'rvdlinden@spd.aas.org' instead. # # To unsubscribe, visit http://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 # #--------------------------------------------------------------------#