Product: Weekly Highlights and Forecasts
:Issued: 2023 May 22 0229 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 15 - 21 May 2023
Solar activity varied from low to high levels. Region 3310 (S20, L=284, class/area=Cko/320 on 19 May) produced the strongest flare of the period, an M9.6 (R2-Moderate) flare at 16/1643 UTC before it fully rotated on to the visible disk from the SE limb. Of the 23 M-class flares (R1-R2 Minor-Moderate) recorded during the period, Region 3311 (N18, L=271, class/area=Ekc/420) was responsible for 21 of them, the largest of which was an M8.9 (R2) flare at 20/1235 UTC. Although the region was the most magnetically complex of the 18 numbered active regions observed on the visible disk during the reporting period, it was in a decaying trend by 21 May.
Other activity included Type II radio sweeps at 16/1731 UTC and 17/1522 UTC, two Tenflares on 20 May, and a filament eruption alongside a CME-producing C4.3/Sf flare at 17/1530 UTC from Region 3309 (S18, L=052, class/area=Cro/020). The subsequent CME signatures in the coronagraph were analyzed and modeled with anticipated effects at Earth suggested late on 21 May.
No proton events were observed in geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit was mostly at the background to moderate levels over the reporting period.
Geomagnetic field activity ranged from quiet to G2 (Moderate) geomagnetic storm levels. Quiet to unsettled levels were observed on 15-16 May and decreased to only quiet levels until of late on 19 May. Active levels were observed during the last synoptic period of 19 May and increased to G2 (Moderate) geomagnetic storm levels early on 20 May. Total magnetic field strength increased to a peak of 21 nT and Bz reached as far south as -17 nT during what appeared to be a CIR, with possible embedded transient, ahead of a negative polarity CH HSS. Bz was persistently southward during the first half 20 May but rotated northward just before midday. With the northward rotation, geomagnetic activity decreased to unsettled to active conditions. On 21 May, another enhancement in the solar wind from an expected CME that left the Sun on 17 May was observed which again resulted in G2 (Moderate) geomagnetic storm levels through the end of the reporting period. With the second enhancement, solar wind speeds increased to between 500-600 km/s and total magnetic field strength briefly reached 13 nT, while the Bz component was observed as far south as -10 nt.
Forecast of Solar and Geomagnetic Activity 22 May - 17 June 2023
Solar activity is expected to be at moderate to high, with a chance for very high, though 30 May, until Region 3311 rotates around the western limb or decays sufficiently to lower its flare potential. Low to moderate solar activity is expected for the remainder of the outlook period.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be high levels from 22 May - 02 Jun in response to recently elevated geomagnetic activity followed by enhanced solar wind from coronal hole influence over the next 6 days. Flux levels
are likely to return to moderate levels from 03-17 Jun.
Geomagnetic field activity is expected to range from quiet to G1 (Minor) geomagnetic storm levels. G1 conditions are likely on 22 May due to persistent transient influence and 23-24 May in response to negative polarity coronal hole influence. Active conditions are anticipated on 02 Jun and 16 Jun with unsettled conditions likely on 25-26 May, 03-05 Jun, and 17 Jun due to multiple recurrent coronal holes. The remainder of the outlook period is likely to be at mostly quiet levels.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2023 May 22 0229 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 2023-05-22
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2023 May 22 160 22 5
2023 May 23 155 18 5
2023 May 24 150 22 5
2023 May 25 155 15 3
2023 May 26 155 10 3
2023 May 27 160 5 2
2023 May 28 160 5 2
2023 May 29 160 5 2
2023 May 30 155 5 2
2023 May 31 155 5 2
2023 Jun 01 150 5 2
2023 Jun 02 155 16 4
2023 Jun 03 155 8 3
2023 Jun 04 155 10 3
2023 Jun 05 160 8 3
2023 Jun 06 165 5 2
2023 Jun 07 160 5 2
2023 Jun 08 155 5 2
2023 Jun 09 150 5 2
2023 Jun 10 145 5 2
2023 Jun 11 145 5 2
2023 Jun 12 150 5 2
2023 Jun 13 155 5 2
2023 Jun 14 155 5 2
2023 Jun 15 160 5 2
2023 Jun 16 165 12 4
2023 Jun 17 165 10 3
(NOAA)
