:Issued: 2025 Apr 27 1230 UTC :Product: documentation at http://www.sidc.be/products/xut #--------------------------------------------------------------------# # GEOALERT message from the SIDC (RWC-Belgium) # #--------------------------------------------------------------------# GEOALERT BRU117 UGEOA 30512 50427 1230/ 9930/ 11272 21272 30272 99999 PLAIN PREDICTIONS FOR 27 Apr 2025 10CM FLUX: 156 / AP: 016 PREDICTIONS FOR 28 Apr 2025 10CM FLUX: 154 / AP: 013 PREDICTIONS FOR 29 Apr 2025 10CM FLUX: 152 / AP: 007 Solar Active Regions and flaring: Solar flaring activity was low over the past 24 hours, only minor C-class flaring was observed. A total of 15 numbered sunspot groups were identified on the disk over the past 24 hours, all with simple alpha or beta magnetic field configuration, and most of them are decaying. The largest flare was a C1.3 one from SIDC Sunspot Group 468 currently located at S15E87, with beta magnetic field confuration. Solar flaring activity is expected to be low over the next 24 hours, with C-class flares expected. Coronal mass ejections: A wide CME erupted towards the north, first seen at 18:00 UTC on 26 April on LASCO C2, but is is not expected to arrive to the Earth. No Earth-directed CMEs were observed in the available coronagraph imagery in the last 24 hours. Coronal holes: There is a large positive polarity coronal hole (SIDC Coronal Hole 104) in the southern hemisphere, although parts of it have rotated out of view over the west limb. In the northern hemisphere, there is one smaller, positive polarity coronal hole, that crossed the central meridian on 24 April. On the eastern part of the Sun, there is a recurrent transequatorial elongated negative polarity coronal hole, SIDC Coronal Hole 99. Solar wind: The solar wind speed has been gradually decreasing to around 400 km/s in the last 24 hours, with an interplanetary magnetic field of 5-10 nT, and Bz mostly positive. In the next 24 hours we may see the arrival of a high speed stream if the solar wind from the positive polarity coronal holes in the southern and/or in the northern hemisphere arrive to the Earth. Geomagnetism: Geomagnetic conditions have been quiet globally and locally (Kp and K_Bel up to 2). The possible arrival of a high speed solar wind stream may increase conditions to active levels. Otherwise, mostly quiet conditions can be expected. Proton flux levels: The greater than 10 MeV proton flux was below the threshold level over the past 24 hours. It is expected to remain below the threshold level over the next 24 hours. Electron fluxes at GEO: The greater than 2 MeV electron flux measured by GOES 18 and 19has been at, or slightly below, the threshold over the past 24 hours. The greater than 2 MeV electron flux may increase over the next 24 hours.The 24-hour electron fluence is presently between normal and moderate levels, it may increase over the next 24 hours. TODAY'S ESTIMATED ISN : 125, BASED ON 19 STATIONS. 99999 UGEOI 30512 50427 1230/ 26/// 1//// 21560 3006/ 4//// 8//// 9//// 99999 NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES NONE END UGEOR 30512 50427 1230/ ///// ///// 99999 USSPS 32404 24079 19732 25004 34803 21405 27002 31832 2/801 28012 42211 37523 30001 32203 2/801 33002 23327 21304 35010 22113 37415 36001 30908 21308 38000 33308 0/101 39003 25918 2/801 40000 33819 01202 41002 14912 21404 42003 18406 2/801 43000 26811 0/101 USSPS 21305 25158 21222 57032 44013 54419 53007 36903 2/803 62003 35519 11304 56005 33532 2/801 64003 32709 11405 71002 40116 1/804 63018 20314 21416 61002 21327 11303 66008 24119 2/801 70005 26518 11308 69001 25112 01204 68011 16105 2/801 67007 13111 11313 USSPS 81202 26005 12122 21000 37401 0/101 22018 44612 21405 25000 33507 0/101 23003 34020 2/801 29011 30302 24406 28000 20916 0/101 33001 12511 01203 32005 23519 2/801 35004 15705 2/801 37000 25717 0/101 UMAGF 30503 50427 1004/ 26060 1/009 21211 31212 UMAGF 31523 50427 0000/ 26000 1/006 21212 32222 #--------------------------------------------------------------------# # 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 # #--------------------------------------------------------------------#