Product: Weekly Highlights and Forecasts
:Issued: 2023 Feb 27 0249 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact https://www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 20 - 26 February 2023
Solar activity reached high levels this week. A total of nine R1 (Minor) events and two R2 (Moderate) events were observed this period. Region 3229 (N26, L=34, class/area=Ekc/310 on 20 Feb) produced two significant flares which were followed by proton flux enhancements and subsequent Earth-directed CMEs. The first event was a long-duration M3/2b flare at 24/2030 UTC with Type-II (1,204 km/s) and Type-IV radio emissions. Shortly following the flare, the greater than 10 MeV proton flux became enhanced, reaching a peak flux of 3 pfu observed at 24/2355 UTC, but did not exceed the event threshold.
The associated CME arrived at Earth beginning at around 26/1845 UTC. The second flare of note from Region 3229 was a long-duration M6/3n flare at 25/1944 UTC with Type-II (528 km/s) radio emissions observed. Shortly following this second flare, the greater than 10 MeV proton flux exceeded the S1 (Minor) solar radiation storm threshold at 25/2110 UTC, and reached a peak flux of 58 pfu at 26/0440 UTC. The partial-halo CME from the M6 flare was determined to have an Earth-directed component and is expected to arrive late on 27/early on 28 Feb.
The greater than 10 MeV proton flux became slightly enhanced late on 24/early on 25 Feb following an M3 flare at 24/2030 UTC from Region 3229. A peak flux of 3 pfu was observed at 24/2355 UTC before flux values slowly decreased to around 1 pfu. An additional enhancement of the greater than 10 MeV proton flux was observed shortly following an M6 flare at 25/1944 UTC from Region 3229. This second proton enhancement exceeded the S1 (Minor) solar radiation storm threshold at 25/2110 UTC, and a peak flux of 58 pfu was observed at 26/0440 UTC. Proton flux values began decreasing over the latter half of 26 Feb, but remained near the 10 pfu event threshold.
The greater than 2 MeV electron flux at geosynchronous orbit was normal to moderate throughout the week.
Geomagnetic field activity was quiet to unsettled on 20 Feb, and quiet to active on 21 Feb, in response to positive polarity CH HSS influence. Quiet conditions prevailed on 22 Feb. G1 (Minor) storm conditions were observed on 23 Feb due to the passage of a CME.
Quiet to unsettled levels were observed over 24-25 Feb, with negative polarity CH HSS influences observed on 25 Feb. G2 (Moderate) storm conditions were observed late on 26 Feb due to a combination of negative polarity CH HSS influences as well as the arrival of the 24 Feb CME. An interplanetary shock (34 nT as measured by Fredericksburg magnetometer) associated with the arrival of the 24 Feb CME was observed at 26/1845 UTC in solar wind data. Following the shock, total magnetic field strength values increased to 21 nT and the Bz component reached -18 nT, solar wind speeds increased to a peak of 756 km/s, and solar wind density increased to 32 ppcm.
Forecast of Solar and Geomagnetic Activity 27 February - 25 March 2023
Solar activity is expected to be elevated throughout the outlook period. A number of regions with a history of producing M-class and X-class flares are expected to return and transit the solar disk over the course of the next 27 days.
The greater than 10 MeV proton event that began at 25/2110 UTC decreased below event threshold at around 27/0000 UTC, but the S1 (Minor) solar radiation warning remains in effect as flux values remain elevated. The anticipated arrival of the 25 Feb CME late on 27 Feb is likely to cause an additional proton flux enhancement as particles are accelerated ahead of the CME. No other proton events are expected during the outlook period, barring additional significant flare activity.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be normal to moderate on 27-28 Feb, and 14-25 Mar. High flux levels are likely on 01-13 Mar following enhanced solar wind conditions and elevated geomagnetic field activity.
Geomagnetic field activity is likely to reach G3 (Strong) storm levels on 27 Feb, and G2 (Moderate) storm levels on 28 Feb, due to a combination of negative polarity CH HSS influence and the anticipated arrival of the 25 Feb CME. G1 (Minor) storms are likely on 06 Mar due to recurrent negative polarity CH HSS influence. Active conditions are likely on 01, 05, 07, 15, and 25 Mar due to multiple, recurrent CH HSSs. Quiet and quiet to unsettled conditions are expected to prevail throughout the remainder of the outlook period.
:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2023 Feb 27 0250 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description & SWPC web contact https://www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2023-02-27
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2023 Feb 27 155 56 7
2023 Feb 28 150 32 6
2023 Mar 01 150 16 4
2023 Mar 02 145 10 3
2023 Mar 03 145 8 3
2023 Mar 04 140 8 3
2023 Mar 05 145 16 4
2023 Mar 06 150 18 5
2023 Mar 07 155 15 4
2023 Mar 08 160 8 3
2023 Mar 09 165 5 2
2023 Mar 10 165 5 2
2023 Mar 11 165 5 2
2023 Mar 12 165 5 2
2023 Mar 13 170 5 2
2023 Mar 14 170 5 2
2023 Mar 15 170 15 4
2023 Mar 16 175 8 3
2023 Mar 17 180 8 3
2023 Mar 18 180 5 2
2023 Mar 19 175 8 3
2023 Mar 20 170 15 3
2023 Mar 21 165 5 2
2023 Mar 22 160 5 2
2023 Mar 23 160 5 2
2023 Mar 24 155 12 3
2023 Mar 25 155 16 4
(NOAA)