Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
336 FXXX12 KWNP 161231 DAYDIS :Product: Forecast Discussion :Issued: 2025 May 16 1230 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # http://www.swpc.noaa.gov/wwire.html # # Forecast Discussion # Solar Activity .24 hr Summary... Solar activity reached moderate levels due to an M2.1/1f at 15/1721 UTC from Region 4087 (N15E32, Dho/beta-gamma-delta). The region produced a few smaller flares and has seen little growth. The region contains a large, symmetric leading spot with a complex trailer whose magnetic field maintains a delta configuration. Region 4088 (N09W63, Cro/beta) saw an increase in size in the leading spots but has been mostly inactive. New Regions 4089 (N16E62, Cso/beta) and 4090 (S12E72, Cso/beta) were numbered and contributed C-class flare activity. No Earth directed CMEs were observed. .Forecast... There remains a 65% chance that M-Class (R1-R2, Minor-Moderate) level flare activity will occur through 18 May with a 30% chance for X-Class (R3-Strong) levels during the same time due to the complex magnetic field within Region 4087. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux has been at moderate levels, nearing threshold during the diurnal maxima. The greater than 10 MeV proton flux has been at background levels. .Forecast... Waning influences from the coronal hole high (CH) high speed stream (HSS) will reduce the chances for the greater than 2 MeV electron flux at geostationary orbit reaching threshold through 18 May. With no complex active regions in the west, the greater than 10 MeV proton flux is expected to remain at background through 18 May. Solar Wind .24 hr Summary... Solar wind parameters displayed waning influences from the CH HSS. Total field (Bt) was around 5-9 nT with a variable north-south (Bz) component between +4/-6 nT. The average wind speeds were around 430 km/s with a predominantly negative (towards the Sun) phi angle. .Forecast... A CME associated with a filament eruption in the northern hemisphere is expected to pass above Earth 17 May, glancing influences will likely enhance the solar wind field during this time. The co-rotating interacting region (CIR) associated with the large, positive polarity CH in the southern hemisphere is expected to become geoeffective 18 May which will further enhance the field. Geospace .24 hr Summary... The geomagnetic field has been at quiet to unsettled levels. .Forecast... A glancing blow from a CME associated with a filament eruption is expected to enhance the geomagnetic field 17 May. Active conditions are expected during this time. The CIR previously mentioned will likely bring continued active conditions, with G1 (Minor) storming likely, on 18 May.