:Issued: 2024 Apr 23 1240 UTC :Product: documentation at http://www.sidc.be/products/xut #--------------------------------------------------------------------# # GEOALERT message from the SIDC (RWC-Belgium) # #--------------------------------------------------------------------# GEOALERT BRU114 UGEOA 30512 40423 1240/ 9930/ 12232 20232 38232 99999 PLAIN PREDICTIONS FOR 23 Apr 2024 10CM FLUX: 210 / AP: 003 PREDICTIONS FOR 24 Apr 2024 10CM FLUX: 207 / AP: 004 PREDICTIONS FOR 25 Apr 2024 10CM FLUX: 204 / AP: 006 Solar Active Regions and flaring: Solar flaring activity remained at moderate levels in the past 24 hours with multiple low M-class flares. There are 18 numbered and several unnumbered active regions on the visible solar disc with NOAA AR 3645 (beta-gamma) being the largest one, followed by NOAA AR 3647 (beta-gamma) and NOAA AR 3639 (beta-gamma). The strongest activity was M3.6 flare, start time 03:06 UTC, end time 03:37 UTC, peak time 03:19 UTC on April 23rd produced by NOAA AR 3654 (beta). This region was responsible for another M3.0-flare, peak time 08:21 UTC on April 23rd and continuous to be actively flaring. Isolated low M-class flaring was produced by regions NOAA 3645 and NOAA 3638. Other regions which contributed to the flaring activity are NOAA AR 3649 (beta), NOAA AR 3656 (beta) and NOAA AR 3646 (beta). The remaining active regions are relatively simple simple (magnetic type alpha or beta) and did not show significant flaring activity. The solar flaring activity is expected to remain at moderate levels over the next days with likely further M-class flaring and increased chances for isolated X-class flaring. Coronal mass ejections: No Earth-directed coronal mass ejections (CMEs) have been detected in the available coronagraph imagery over the past 24 hours. A small filament eruption was observed to the south of the central meridian starting around 1:40 UTC on April 23rd. A related chain of flaring activity was observed from regions NOAA 3654 (M3.4 flare, peak time 03:19 UTC on April 23rd) and region NOAA AR 3638 (C-class flaring, peaking at 01:22 UTC and 07:04 UTC on April 23rd) with an eastward and series of south-west CMEs detected by LASCO/C2 around 03:48 UTC and 07:36 UTC. Current analysis is ongoing to determine any potential Earth-directed components related to these eruptions. Solar wind: Over the past 24 hours the solar wind parameters (ACE and DSCOVR) were indicative of background slow solar wind regime. The solar wind velocity was in the range of 335 km/s to 456 km/s. The interplanetary magnetic field was weak with a maximum value of 3.36 nT and a minimum Bz of -5.06 nT. The B field phi angle was predominantly in the negative sector (directed towards the Sun). The solar wind conditions are expected to remain at slow solar wind conditions in the next hours with possible mild elevations due to possible high speed stream arrival from a positive polarity coronal hole on April 25th - April 26th. Geomagnetism: The geomagnetic conditions over the past 24 hours were globally quiet and locally in Belgium quiet to unsettled. Mostly quiet to unsettled geomagnetic conditions are expected throughout April 23rd and 24th. Quiet to active conditions with chances for isolated minor storms are anticipated for late April 25th-April 26th. Proton flux levels: Over the past 24 hours the greater than 10 MeV GOES proton flux was at background levels and is expected to continue so over the next days, pending any fast eruptive solar activity. Electron fluxes at GEO: The greater than 2 MeV GOES 16 electron flux as measured by GOES 16 was below the 1000 pfu threshold and might reach the 1000 pfu threshold over the next 24h. The greater than 2 MeV electron flux as measured by GOES 18 briefly exceeded 1000 pfu threshold around 17 UTC and midnight UTC on April 22nd and is expected to cross the 1000 pfu threshold again in the late afternoon on April 23rd. The 24h electron fluence was at nominal level and is expected to remain so. TODAY'S ESTIMATED ISN : 279, BASED ON 12 STATIONS. 99999 UGEOI 30512 40423 1240/ 22/// 1//// 2//// 3//// 4//// 8//// 9//// 99999 NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES 22 1313 1335 1417 S10W39 M1.6 1N 60/3645 VI/2 22 1446 1455 1508 N23E07 M1.1 1F 60/3645 22 1508 1519 1532 N23E07 M1.6 1F 64/3646 22 1541 1550 1558 S11E67 M2.8 SN ///3656 III/3 22 1626 1630 1636 ////// M1.0 ///3656 III/2 22 2105 2116 2124 S17W48 M1.5 1N 59/3638 VI/1III/3II/3 23 0306 0319 0335 ////// M3.6 ///3654 III/1 23 0807 0821 0829 S05E41 M3.0 1B ///3654 VI/1 END UGEOR 30512 40423 1240/ ///// ///// 99999 USSPS 32404 21070 22132 23002 34721 2/801 25002 32518 01210 27012 41928 27511 28003 30615 21314 30004 11814 21403 31012 32408 51414 32000 12322 01204 33012 31813 37415 34000 10818 0/101 36002 20311 21310 38002 14115 01206 39000 27008 0/101 40000 17003 0/101 USSPS 21305 21155 31332 43001 44217 2/801 35024 41729 34521 45001 10519 0/801 40005 11522 34410 39009 11716 2/802 49007 11213 2/802 48007 13519 34408 50001 16503 0/801 30002 35721 2/801 34005 32816 24316 41049 32508 54521 44029 32113 54427 38003 31213 3/811 46008 30111 34318 52004 26809 3/801 53001 28012 0/101 51001 27027 0/101 USSPS 81202 22020 33332 21001 45015 01202 17017 43027 21418 18009 10915 2/803 19010 11222 21316 25011 13018 21306 20045 33509 47436 23010 30810 21311 26001 24510 01202 28003 26007 0/103 30003 27510 0/103 10001 35523 0/101 12007 33518 01216 22023 32513 47436 15005 31515 01210 29005 26525 01207 24006 10515 2/803 #--------------------------------------------------------------------# # 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 # #--------------------------------------------------------------------#