####018002401#### FXXX12 KWNP 181231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Feb 18 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 was at low levels. The largest flare of the period was a C7.9 at 17/1834 UTC from Region 3584 (S13W27, Cro/beta). Slight growth was observed in Region 3584. Region 3583 (N09W59, Fki/beta) produced lower C-class flares. This region displayed moderate growth in the intermediate spots. The rest of the spotted regions were relatively stable or in decay. C-flare activity was also observed from behind the NE and SW limbs. A partial halo CME was observed beginning at 17/1336 UTC in coronagraph imagery with the majority of the ejecta off the SE limb. This was determined to be backsided. No Earth-directed CMEs were observed. .Forecast... Solar activity is expected to be low with a chance for M-class flares (R1-R2/Minor-Moderate) on 18-20 Feb. Energetic Particles .24 hr Summary... The greater than 10 MeV proton flux remained enhanced, but well below the S1 (Minor) threshold, following the X2.5 flare on 16 Feb. The greater than 2 MeV electron flux was at normal to moderate levels. .Forecast... The greater than 10 MeV proton flux is expected to decrease to background levels over 18-20 Feb. The greater than 2 MeV electron flux is expected to continue at normal to moderate levels. Solar Wind .24 hr Summary... Solar wind parameters were at nominal levels. Total field increased from 5 nT to 8 nT while the Bz component was between +5/-6 nT. Solar wind speeds were unreliable between the ACE and DISCOVR satellites. Phi angle was mostly positive. .Forecast... Nominal conditions are likely on 18 Feb through midday on 19 Feb. By late on 19 Feb to early on 20 Feb, a potential grazing from the 16 Feb CME is likely to cause a weak enhancement. Geospace .24 hr Summary... The geomagnetic field was at quiet to isolated unsettled levels. .Forecast... Mostly quiet conditions are expected on 18 Feb through midday on 19 Feb. By late on 19 Feb to early on 20 Feb, weak CME activity is likely to cause unsettled conditions. ####018002105#### FXXX10 KWNP 181231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Feb 18 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 Feb 18-Feb 20 2024 is 3.33 (below NOAA Scale levels). NOAA Kp index breakdown Feb 18-Feb 20 2024 Feb 18 Feb 19 Feb 20 00-03UT 3.33 1.67 2.67 03-06UT 2.00 1.33 2.67 06-09UT 1.00 1.33 2.33 09-12UT 1.67 1.67 2.33 12-15UT 1.33 1.33 2.33 15-18UT 1.33 1.33 2.33 18-21UT 1.67 3.00 2.00 21-00UT 1.67 3.33 2.33 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 Feb 18-Feb 20 2024 Feb 18 Feb 19 Feb 20 S1 or greater 5% 5% 5% 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 Feb 18-Feb 20 2024 Feb 18 Feb 19 Feb 20 R1-R2 40% 40% 40% R3 or greater 5% 5% 5% Rationale: here is a chance for R1-R2 (Minor-Moderate) events over 18-20 Feb.