Thursday, December 28, 2023

Weekly Propagation Forecast Bulletins

 Product: Weekly Highlights and Forecasts

:Issued: 2023 Dec 25 0302 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 December 2023


Solar activity was at low to moderate (R1-Minor) levels over the past week. Moderate levels were observed on 21-22 Dec and 24 Dec. The strongest event was an M4.2/1n flare (R1) at 21/0538 UTC from Region 3519 (S12, L=71, class/area=Dai/180 on 21 Dec). Other, lower, M-class (R1) events were observed from Region 3529 (S19, L=345, class/area=Dko/450 on 20 Dec) and event from just beyond the SE limb on 24 Dec. The other 18 numbered active regions either produced only C-class activity or were relatively quiet. 

Other activity included a ~22-degree filament eruption, centered near N48W35, that began around 24/0920 UTC. A subsequent CME signature was observed in SOHO/LASCO C2 imagery at 24/1224 UTC. Another CME from a filament eruption, centered near S20E48, was observed after 24/1438 UTC. Modeling of the two events suggested a potential glancing blow late on the 27th and in to the 28th of Dec. No other Earth-directed CMEs were identified in available coronagraph imagery. 

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 21-22 Dec due to elevated geomagnetic activity earlier in the week. The remainder of the period was at normal to moderate levels. 

Geomagnetic field activity ranged from quiet to G2 (Moderate) geomagnetic storm levels. G2 conditions observed on 28 Dec were in response to the waning portion of a CME that left the Sun over 14-15 Dec. Solar wind speeds were just under 500 km/s and the Bz component was near -10 nT around the time of the activity. Conditions decreased to active levels as transient influence weakened over 19-20 Dec. Mostly quiet to unsettled levels were observed for the remainder of the week (21-24 Dec). 

Forecast of Solar and Geomagnetic Activity 25 December - 20 January 2024

Solar activity is expected to be at low levels, with a chance for moderate levels (R1-R2/Minor-Moderate), throughout the outlook period. Increased potential for activity is due to multiple R1 events or greater producing regions either on the visible disk or due to return in the coming weeks. 

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels over 31 Dec - 05 Jan and 09-12 Jan due to multiple anticipated CH HSSs. The remainder of the outlook period is likely to be at moderate levels. 

Geomagnetic field activity is expected to range from quiet to active levels. Active levels over 27-28 Dec are due to potential CME influence. Active conditions on 30 Dec and unsettled conditions on 31 Dec - 02 Jan and 08-10 Jan are likely due to anticipated influence from multiple, recurrent CH HSSs. The remainder of the outlook period is likely to be mostly quiet. 

:Product: 27-day Space Weather Outlook Table 27DO.txt
:

Issued: 2023 Dec 25 0303 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#
#      27-day Space Weather Outlook Table
#                Issued 2023-12-25
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2023 Dec 25     180           5          2
2023 Dec 26     170           5          2
2023 Dec 27     165          10          4
2023 Dec 28     162          12          4
2023 Dec 29     155           5          2
2023 Dec 30     145          12          4
2023 Dec 31     140          10          3
2024 Jan 01     140           8          3
2024 Jan 02     140           8          3
2024 Jan 03     140           5          2
2024 Jan 04     150           5          2
2024 Jan 05     150           5          2
2024 Jan 06     150           5          2
2024 Jan 07     150           5          2
2024 Jan 08     155          10          3
2024 Jan 09     155          10          3
2024 Jan 10     155           8          3
2024 Jan 11     155           5          2
2024 Jan 12     150           5          2
2024 Jan 13     155           5          2
2024 Jan 14     160           5          2
2024 Jan 15     170           5          2
2024 Jan 16     175           5          2
2024 Jan 17     180           5          2
2024 Jan 18     180           5          2
2024 Jan 19     180           5          2
2024 Jan 20     180           5          2
(NOAA)