[Ips-dsgr] ASWFC Daily Report - 29 December 24 issued 2330 UT on 29 Dec 2024 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Mon Dec 30 10:30:49 AEDT 2024


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/29 DECEMBER 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 29 DECEMBER AND FORECAST FOR 30 DECEMBER - 01 JANUARY
STATUS INDICATORS SOL:** RED **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 29 Dec:  R3

Flares    Max     Fadeout    Freq.  Sectors
  M1.2 28/2214UT  possible   lower  East Pacific/
                                    North American
  M1.0    0235UT  possible   lower  E. Asia/Aust.
  M2.0    0430UT  possible   lower  E. Asia/Aust.
  M3.1    0526UT  possible   lower  E. Asia/Aust.
  X1.1    0718UT  probable   all    Mid East/Indian
  M1.6    1224UT  possible   lower  European
  M1.1    1429UT  possible   lower  South American/
                                    Atlantic
  M7.1    1509UT  probable   lower  South American/
                                    Atlantic
  M3.3    1708UT  possible   lower  South American/
                                    Atlantic
  M1.1    2039UT  possible   lower  East Pacific/
                                    North American
  M1.5    2153UT  possible   lower  East Pacific/
                                    North American

Observed 10.7 cm flux/Equivalent Sunspot Number for 29 Dec: 255/205


1B. SOLAR FORECAST
             30 Dec             31 Dec             01 Jan
Activity     R1-R3              R1-R3              R1-R3
Fadeouts     Probable           Probable           Probable
10.7cm/SSN   255/205            240/189            210/161

COMMENT: Solar activity on UT day 29-Dec reached R3, with an 
X1.1 solar flare at 0718 UT. Solar activity on UT day 29-Dec 
was complex: the X-ray flux was above M-class levels for a majority 
of the day, with approximately 6-7 sunspot regions contributing 
to continuous sympathetic flare activity. At least ten M-class 
flares were observed throughout the day, as well as one X-class 
flare. The contributing sunspot regions were AR3932 (S17W50, 
beta-gamma), AR3933 (S08W74, beta-gamma), AR3936 (N13W42, beta-delta), 
AR3938 (N19W01, beta-gamma), AR3939 (S17E21, beta) plus possibly 
two regions behind the west and eastern solar limbs. ARs 3933, 
3936, 3939 and 3941 have all grown over the past day, with AR3936 
being the most complex region on the disk currently. All other 
sunspots are either stable or in decay. Solar activity is expected 
to be R1-R3 over 30-31 Dec and 01-Jan; background X-ray flux 
levels may continue to be at M-class levels on 30-Dec. 

Several CMEs were observed on UT day 29-Dec. A faint and slow CME was 
observed to the south from 29/0200 UT, and is expected to have 
a weak impact to earth from UT day 01-Jan. A partial halo CME 
was observed from 29/0624 UT, likely associated with M-class 
flare activity from AR3939. This CME is expected to arrive at 
Earth from late in the UT day 31-Dec. Two CMEs directed to the 
solar southwest and northest were observed from 0912 UT, although 
analysis is ongoing to determine the origin of this. From 1848 
UT a weak CME can be seen directed to the south, likely originating 
from AR3939. This CME is expected to arrive mid 01-Jan. 

S0 solar radiation storm conditions were observed on UT day 29-Dec. 
S0 solar radiation storm conditions are expected over 30-31 Dec 
and 01-Jan.

 The solar wind was mostly undisturbed on UT day 29-Dec. 
The peak total interplanetary field strength (IMF, Bt) was 11 
nT and the north-south IMF component range (Bz) was +9 to -7 
nT. The solar wind speed was steady near 350 km/s for the first 
three quarters of the UT day, before increasing to near 400 km/s 
for the remainder. The solar wind environment is expected to be 
at background levels on 30-Dec and the first half of 31-Dec. 
>From late 31-Dec, the solar wind environment is expected to become 
disturbed due to a CME arrival; conditions are expected to continue 
into 01-Jan by when another CME is expected to arrive.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 29 Dec: G0

Estimated Indices 29 Dec : A   K           
   Australian Region       4   11221112
      Cocos Island         3   11221101
      Darwin               4   10121113
      Townsville           6   21222222
      Learmonth            6   21232202
      Alice Springs        4   00221103
      Gingin               6   21231103
      Canberra             4   11221102
      Kennaook Cape Grim   -   --------
      Hobart               6   11331112    

Estimated Antarctic Regional K Indices 29 Dec :
      Macquarie Island     3   01221002
      Casey               24   24653212
      Mawson              11   32343201

Observed Regional daily pc3 Indices 29 Dec : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (Quiet)

Pc3 pulsations are high frequency (10-45 second period) variations 
of the Earths magnetic field. Daily pc3-indices are the daily sum 
of 20 minute pc3-indices for that station and have been shown to be
well correlated with rejection of high resolution aeromagnetic
survey flight-line data. 

NOTE: Indices may have been generated from data obtained in 
cooperation with the following organisations: Geoscience Australia, 
University of Newcastle Space Physics Group, Australian Government 
Antarctic Division and International Center for Space Weather 
Science and Education, Japan.


Estimated AFr/Ap Indices 29 Dec : A 
           Fredericksburg         5
           Planetary              6                         

Observed AFr/Ap Indices 28 Dec :  A   K
           Fredericksburg         4
           Planetary              3   0101 0221     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
30 Dec     6    G0
31 Dec    20    G2, chance G3
01 Jan    25    G1-22, chance G3

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 29-Dec. G0-G2 geomagnetic conditions were observed 
in the Antarctic region. G0 geomagnetic conditions are expected 
on UT day 30-Dec. By late 31-Dec, a CME arrival is expected to 
induce G2, with a chance for G3 geomagnetic conditions. This 
geomagnetic activity is expected to continue into 01-Jan. Two 
other CME arrivals are possible on 01-Jan, contributing to the 
enhanced geomagnetic activity.

-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
29 Dec      Normal         Normal         Normal-fair    

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
30 Dec      Normal         Normal         Normal-fair
31 Dec      Normal         Normal-fair    Fair
01 Jan      Normal         Fair           Fair-poor

COMMENT: HF radio propagation conditions were generally normal, 
with some mild degradations at high latitudes and also in the 
local night sector. Lower frequencies may have been affected 
for much of the day for daylight HF circuits due to high levels 
of background X-ray flux. HF radio propagation is expected to 
be at similar conditions on UT day 30-Dec; degradations are expected 
to increase late on 31-Dec due to anticipated geomagnetic activity, 
and continue into 01-Jan.

-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
29 Dec   157

Observed Australian Regional MUFs
   Cocos Island Region:
      Near predicted monthly values.
   Niue Island Region:
      Enhanced by 20% during local day.
      Enhanced by 25% during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Enhanced by 15% during local day.
      Enhanced by 15% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Nov      127
Dec      117
Jan      114

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
30 Dec   160    Near to 25% above predicted monthly values
31 Dec   150    Near to 25% above predicted monthly values
01 Jan   130    Near predicted monthly values to 20% depressed

COMMENT: ASWFC SWF HF Communications Warning 149 was issued on 
27 December and is current for 28-30 Dec. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 29-Dec were near predicted 
values to 15% enhanced. Sporadic-E was common at most sites during 
local night hours, however appears to be decreasing in intensity 
and duration. Lower frequencies on daylight HF circuits may have 
been degraded due to high background X-ray flux levels. MUFs 
are expected to be near predicted values to 25% enhanced over 
30-31 Dec, before becoming depressed by 20% on 01-Dec due to 
anticipated geomagnetic activity.

-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 28 Dec
       Daily Proton Fluence >1 MeV:   9.0E+05
       Daily Proton Fluence >10 MeV:  3.0E+04
       Daily Electron Fluence >2 MeV: 1.80E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 3%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C3.6

DSCOVR Satellite Solar Wind Day Averaged Data for 28 Dec
Speed: 306 km/sec  Density:    3.9 p/cc  Temp:    21200 K  Bz:   1 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
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Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au



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