####018002186#### FXXX10 KWNP 111231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Apr 11 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 # # 3-Day Forecast # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 11-Apr 13 2024 is 2.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 11-Apr 13 2024 Apr 11 Apr 12 Apr 13 00-03UT 2.33 1.67 2.33 03-06UT 2.67 1.33 1.67 06-09UT 0.67 1.33 2.00 09-12UT 1.00 1.33 1.67 12-15UT 2.33 1.33 2.00 15-18UT 2.33 1.33 2.33 18-21UT 2.33 1.67 2.33 21-00UT 2.67 1.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 11-Apr 13 2024 Apr 11 Apr 12 Apr 13 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 11-Apr 13 2024 Apr 11 Apr 12 Apr 13 R1-R2 10% 25% 25% R3 or greater 1% 5% 5% Rationale: There is an increasing chance for R1-R2 (Minor-Moderate) radio blackouts over the next three days-primarily due to the return of old Region 3615. ####018002738#### FXXX12 KWNP 111231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Apr 11 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 low levels, with numerous low level C-class flares observed. Most of the flare activity was produced by regions beyond the east and west limbs. Region 3628 (N08W35, Hsx/alpha) exhibited decay and remained quiet. Region 3633 (S08E12, Cso/beta-gamma) continued to decay while producing C-class activity. Region 3635 (N19E41, Cso/beta) was numbered this period, but was otherwise unremarkable. From ~11/0515-0605 UTC, an approximately 15 degree long filament, centered near N20W02, was observed lifting off the solar disk. Corresponding dimming was observed in SUVI 195 imagery, and a filament eruption was observed lifting off to the east in SUVI 304. The resulting coronagraph imagery is being analyzed and modeled at the time of this summary. No other potentially Earth-directed CMEs were observed. .Forecast... Solar activity will likely to continue at low levels on 11 Apr with a slight chance for M-class flare activity. Probabilities increase for 12-13 Apr to a chance for isolated M-class flare activity with the anticipated return of old AR 3615. Energetic Particles .24 hr Summary... The greater than 10 MeV proton flux was at background levels. The greater than 2 MeV electron flux was at normal to moderate levels. .Forecast... The greater than 10 MeV proton flux is expected to remain at background levels. The greater than 2 MeV electron flux is expected to continue at normal to moderate levels through 13 Apr. Solar Wind .24 hr Summary... Solar wind parameters reflected weak positive polarity CH HSS influences. Total field ranged 1-7 nT, the Bz component was +/- 6 nT with no significant, sustained southward deflections, and solar wind speeds averaged near 450 km/s. Phi was predominantly positive. .Forecast... Weak enhancements in the solar wind environment are anticipated to wane over the course of 11 Apr, with a return to nominal conditions on 12 Apr. Disturbances are expected once again on 13 Apr due to negative polarity CH HSS influences. Geospace .24 hr Summary... The geomagnetic field was at quiet to unsettled levels. .Forecast... Quiet to unsettled conditions, with a chance for isolated active periods, are expected on 11 and 13 Apr due to CH HSS effects. A primarily quiet environment is expected on 12 Apr.