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Tuesday, September 19, 2023

Weekly Propagation Forecast Bulletins

 


Product: Weekly Highlights and Forecasts
:Issued: 2023 Sep 18 0138 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 11 - 17 September 2023

Solar activity ranged from low to moderate (R1 - Minor) levels. Low levels were observed on 13 and 17 Sep while moderate levels were observed on 11-12 and 14-16 Sep. Regions 3423 (N16, L=281, class/area Ekc/420 on 11 Sep), 3425 (N23, L=246, class/area Dai/140 on 08 Sep) and 3429 (N11, L=207, class/area Dai/090 on 15 Sep) were responsible for the moderate levels activity. The largest event of the period was an M3.3/1b flare from Region 3429. 

A filament eruption in the vicinity of Region 3423 (N15W72, Eko/beta) produced an M1 flare that began at 14/0640 UTC. The x-ray flare reached a peak of M1.4 at 14/0745 UTC due to a contributing flare from Region 3429 (N10E05, Eai/beta) which obscured the natural x-ray peak of the filament eruption. The filament eruption produced a CME signature, first visible in SOHO/LASCO C2 imagery at 14/0712 UTC. Analysis and model output suggested an Earth arrival early on 17 Sep. 

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at low to moderate levels through the period. 

Geomagnetic field activity ranged from quiet to G2 (Moderate) levels. Quiet levels were observed on 11 Sep through midday on 12 Sep. Unsettled to G2 (Moderate) levels were observed from midday on 12 Sep through 13 Sep due to CME and positive polarity CH HSS effects. Unsettled to active levels were observed on 14-15 Sep due to positive polarity CH HSS on 14 Sep and negative polarity CH HSS effects on 15 Sep. Mostly quiet levels were observed on 16 Sep. Unsettled to active levels were observed on 17 Sep due to transient effects from the 14 Sep CME. 

Total field readings, through the period, generally averaged 4-7 nT with a peak to 21 nT midday to late on 12 Sep. The Bz component reached a maximum southward reading of -20 nT late on 12 Sep. Wind speeds ranged from lows near 340 km/s on 11-12 Sep to a high reading of 525 km/s midday to late on 14 Sep. 

Forecast of Solar and Geomagnetic Activity 18 September - 14 October 2023

Solar activity is expected to be at low to moderate (R1-R2 / Minor to Moderate) levels throughout the period. 

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at low to moderate levels through the period. 

Geomagnetic field activity is likely to be at G1-G2 (Minor to Moderate) levels on 19 Sep and unsettled to active levels on 20 Sep, all due to CME effects. Unsettled to active levels are likely on 21, 23-24 and 28-30 Sep due to CH HSS activity. Mostly quiet levels are expected on 18, 25-27 Sep and 01-14 Oct. 

:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2023 Sep 18 0139 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 2023-09-18
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2023 Sep 18     145           8          3
2023 Sep 19     140          35          6
2023 Sep 20     140          15          4
2023 Sep 21     140           8          3
2023 Sep 22     140           5          2
2023 Sep 23     140          12          4
2023 Sep 24     140           8          3
2023 Sep 25     145           5          2
2023 Sep 26     140           5          2
2023 Sep 27     140           5          2
2023 Sep 28     135           8          3
2023 Sep 29     135          12          4
2023 Sep 30     135           8          3
2023 Oct 01     140           5          2
2023 Oct 02     145           5          2
2023 Oct 03     150           5          2
2023 Oct 04     155           5          2
2023 Oct 05     155           5          2
2023 Oct 06     155           5          2
2023 Oct 07     160           5          2
2023 Oct 08     160           5          2
2023 Oct 09     155           5          2
2023 Oct 10     150           5          2
2023 Oct 11     150           5          2
2023 Oct 12     145           5          2
2023 Oct 13     145           5          2
2023 Oct 14     145           5          2
(NOAA)