Product: Weekly Highlights and Forecasts
:Issued: 2024 Mar 25 0644 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 18 - 24 March 2024
Solar activity during the week reached high levels. The largest flare was an X1.1/ 2F at 23/0133 UTC. Region 3614 (N17, L=224, Dso-B/210 on 23 Mar) produced the flare which appeared along a filanment channel to the north of the spot group. A 240 SFU 10cm radio burst and Type II sweep (791 km/s) were observed. The flare was also accompanied by an EUV wave, dimming and post-eruptive arcades visible in GOES SUVI 195 Angstrom imagery. An asymmetric halo cme was first visible in SOHO/LASCO C2 imagery at 23/0048 UTC. Plane of sky measurments averaged from C2 and C3 suggested the CME was moving at 1492 km/s. While Region 3614 produced the largest flare of the week, Region 3615 (S13, L-215, Fkc-BGD/810 on 24 March) was the most prolific. It produced 27 M-class flares during the week, three of which were greater than M5 (R2). The largest was an
M7.4, 3B on 20/0736 UTC.
The X1.1 and CME described above triggered a 10 MeV proton event. The 10 MeV flux began rising at 23/0400 UTC, crossed the 10 pfu (S1) threshold at 23/0815 UTC and the 100 pfu (S2) threshold at 23/1405 UTC. The event peaked on 23/1820 UTC at 956 pfu. A second peak of 687 pfu was observed at 24/1230 UTC as the CME described earlier approached.
The greater than 2 MeV electron flux at geosynchronous orbit ranged from normal to moderate levels throughout the week.
Four distinct geomagnetic storms ocurred during the week. The first was associated with a CME arrival at 21/0225 UTC. Bz dipped southward to -12 nt and, and a couple of periods of prolonged southward Bz led to three synoptic periods of minor (G1) geomagnetic storm conditions between 21/1200-2100 UTC. The second even began on 22/2320 UTC Bz shifted southward around 23/0100 UTC and remained there for about 7 hours. This gave rise to two periods of minor (G1) geomagnetic storm conditions between 23/0300-0900 UTC.
This activity was most likely a CIR, in advance of a negative polarity coronal hole, based on the density increase and rotation of the Phi angle .Solar wind speed and temperature began rising at the end of the storm activity, suggesting the high-speed stream had become geoeffective. The third storm began with the 23/1800 UTC UTC synoptic period (Kp=5-, G1), peaked during the 2100-0000 UTC
synoptic period, reaching Kp=6- (G2), and returned to G1 conditions for the final period from 24/0000 UTC to 24/0300 UTC. The final storm began with the arrival of the CME described in the first paragraph. The interplanetary shock arrived at L1 at 24/1411 UTC and a sudden impulse (377 nT at Meanook Observatory) was detected at 24/1437 UTC.
Solar wind speed jumped from the 500-550 km/s high speed stream values to approximately 800 km/s and remained elevated. Bz dipped southward to -27 nT at 24/1510 UTC. Kp ranged from 6+ (G2) moderate storm conditions to 8o (G4) sever conditions between 24/1200-2100 UTC. The severe synoptic period was from 24/1500-1800 UTC. The magnetic cloud appears to have arrived around 24/1826 UTC distinguised by a slow rotation of the Phi angle. Earth was still within the magnetic cloud at the end of this reporting period.
Forecast of Solar and Geomagnetic Activity 25 March - 20 April 2024
The threat of high solar activity remains throughout the coming week. Region 3615 (Fkc-BGD) is expected to remain on the visible disk until March 29th-30th. The departure of Region 3615 is anticipated to bring a period of low solar activity with a lingering chance for M flares. Regions 3614 and 3615 are expected to return on April 11th, increasing the potential for moderate to high activity.
Along with the high solar activity, there is a chance for another proton event at geosynchronous orbit, with the greatest threat from Region 3615 until it departs. The threat will decrease until the region returns on April 11th.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at moderate to high levels during the forecast period. The high levels are anticipated between March 28th-31st, and again from 6-8 April in the wake of coronal holes.
The beginning of the forecast period is expected to see strong (G3) geomagnetic conditions declining to mostly quiet conditions after March 26th. Levels will increase to potentially minor (G1) levels with the influence of a coronal hole high speed stream on April 3rd-5th. High speed streams on April 9th-11th and 19th-20th are expected to bring less than minor (G1) storm conditions. The threat of more CMEs and subsequent storms associated with Regions 3614 and 3615, or with new regions that emerge, remains.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2024 Mar 25 0644 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2024-03-25
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2024 Mar 25 200 50 7
2024 Mar 26 205 22 5
2024 Mar 27 210 5 2
2024 Mar 28 210 5 2
2024 Mar 29 205 5 2
2024 Mar 30 190 5 2
2024 Mar 31 180 5 2
2024 Apr 01 175 5 2
2024 Apr 02 175 5 2
2024 Apr 03 170 15 4
2024 Apr 04 180 12 4
2024 Apr 05 185 12 4
2024 Apr 06 190 5 2
2024 Apr 07 190 5 2
2024 Apr 08 185 5 2
2024 Apr 09 180 8 3
2024 Apr 10 175 8 3
2024 Apr 11 185 8 3
2024 Apr 12 185 5 2
2024 Apr 13 185 5 2
2024 Apr 14 190 5 2
2024 Apr 15 185 5 2
2024 Apr 16 190 5 2
2024 Apr 17 185 5 2
2024 Apr 18 180 5 2
2024 Apr 19 175 8 3
2024 Apr 20 175 10 3
(NOAA)
