[Ips-dsgr] ASWFC Daily Report - 21 January 25 issued 2330 UT on 21 Jan 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Wed Jan 22 10:30:49 AEDT 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/21 JANUARY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 21 JANUARY AND FORECAST FOR 22 JANUARY - 24 JANUARY
STATUS INDICATORS SOL:** YELLOW **   MAG:** RED **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 21 Jan:  R1

Flares    Max     Fadeout    Freq.  Sectors
  M3.3    1037UT  possible   lower  European

Observed 10.7 cm flux/Equivalent Sunspot Number for 21 Jan: 225/175


1B. SOLAR FORECAST
             22 Jan             23 Jan             24 Jan
Activity     R1,chance R2       R1,chance R2       R1,chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   225/175            225/175            220/170

COMMENT: Solar activity on UT day 21-Jan was R1 due to an M3.3 
flare from solar region AR3967 (S14E18, beta-gamma) which has 
shown growth over the past 24 hours and this region currently 
consists of several small spots. Large solar region AR3961 (S10W19, 
beta-gamma) has increased in overall longitudinal extent but 
exhibits a more open spot configuration. The trailer spots show 
significant decay and intermediate spots show some decline/redistribution 
with the growing intermediate penumbral area now a finger like 
extension between the trailer and leader spots. The three umbras 
in the main leader spot of AR3961 have converged. Overall this 
region's recent evolution is suggesting decay. Solar region AR3959 
(N19W41, beta) which consist mainly of a large spot has shown 
some decay in its surrounding penumbra. A recent medium sized 
region of interest AR3964 (N11W86, beta) is rotating over the 
northwest solar limb and very small region AR3968 which recently 
showed some growth and produced yesterday's minor C6.3 flare 
has rotated over the southwest solar limb. Plasma ejecta was 
observed off the northern polar limb in GOES SUVI 304 imagery 
from 21/0441UT and was also observed to the southeast from 21/1053UT. 
There are currently nine numbered sunspot regions on the solar 
disk. Other regions are either stable or in decay. Solar activity 
is expected to be R1, chance R2 over 22-24 Jan. S0 solar radiation 
storm conditions were observed on UT day 21-Jan. S0 solar radiation 
storm conditions are expected over 22-24 Jan. A partially Earth 
directed CME has been observed. A CME to the southeast was observed 
from 21/0924UT associated with the M3.3 flare and the southeast 
directed plasma ejecta. Modelling of this mainly southeast CME 
was difficult due to a data gap 21/1000-1500UT in LASCO C2/C3 
imagery and was conducted mainly using STEREO-A coronagraph imagery 
and shows an Earth arrival time of 24/2100UT +/- 12 hours with the 
bulk of the CME missing the Earth. A north directed CME was observed 
from 21/0348UT probably associated with the plasma ejecta from 
the northern solar limb and is directed away from the Earth out 
of the ecliptic plane. A narrow CME was observed to the southwest 
from 21/0848UT and is considered a behind the limb event possibly 
from AR3968 which has recently rotated off disk. The solar wind 
environment on UT day 21-Jan declined as coronal hole wind stream 
influences reduced. The solar wind speed ranged from 670 to 500 
km/s, and is currently near 500 km/s. The peak total interplanetary 
field strength (IMF, Bt) was 6 nT and the north-south IMF component 
range (Bz) was +3 to -4 nT. The IMF Bz component was very mildly 
southwards 21/1654-2204UT. The solar wind speed is expected to 
continue to decline over 22-23 Jan. A weak solar wind shock arrival 
is expected mid to late 24-Jan from the M3/CME.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 21 Jan: G0

Estimated Indices 21 Jan : A   K           
   Australian Region       8   22222232
      Cocos Island         4   21111121
      Darwin               6   22221222
      Townsville           6   22221222
      Learmonth            9   22222332
      Alice Springs        6   22221222
      Gingin              11   32222342
      Canberra             7   22222222
      Kennaook Cape Grim   8   22222232
      Hobart               8   22222232    

Estimated Antarctic Regional K Indices 21 Jan :
      Macquarie Island     7   22222321
      Casey               25   55523233
      Mawson              39   34532375

Observed Regional daily pc3 Indices 21 Jan : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            6   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin              34   (Quiet to unsettled)
      Canberra            22   (Quiet to unsettled)

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 21 Jan : A 
           Fredericksburg         8
           Planetary             11                         

Observed AFr/Ap Indices 20 Jan :  A   K
           Fredericksburg        13
           Planetary             15   3322 5332     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
22 Jan    11    G0
23 Jan     8    G0
24 Jan    20    G0-G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 21-Jan. In the Antarctic region Macquarie Island 
was at G0, Casey was G1 for the first half of the UT day and 
Mawson briefly reached G3. G0 geomagnetic conditions are expected 
over 22-23 Jan as coronal hole effects decline. A glancing blow 
CME arrival is expected late in the UT day on 24-Jan with G1 
periods possible late 24-Jan and first half of 25-Jan.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
21 Jan      Normal         Fair-normal    Fair-normal    

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
22 Jan      Normal         Normal         Normal-fair
23 Jan      Normal         Normal         Normal
24 Jan      Normal         Normal-fair    Normal-fair

COMMENT: HF radio propagation conditions on UT day 21-Jan were 
fair to normal, with some mild degradations at middle to high 
latitudes. HF radio propagation conditions are expected to be 
normal over 22-23 Jan. Mildly degraded HF conditions may be experienced 
at middle to high latitudes from late 24-Jan and into 25-Jan 
due to a possible glancing blow CME arrival. Isolated minor fadeouts 
possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
21 Jan   144

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Niue Island Region:
      Enhanced by 15%.
   Northern Australian Region:
      Enhanced by 20-40%.
   Southern Australian Region:
      Mostly near predicted monthly values.
      Depressed 15-20% early in the UT day.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Dec      132
Jan      119
Feb      116

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
22 Jan   125    Near predicted monthly values
23 Jan   125    Near predicted monthly values
24 Jan   125    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 11 was issued on 
21 January and is current for 21-23 Jan. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 21-Jan varied from 
15-20% depressed in the southern Australian region during the 
local day to 20-40% enhanced in the northern Australian region. 
MUFs are expected to be near predicted monthly values for 22-24 
Jan as the recent mild increase in geomagnetic activity from 
a coronal hole wind stream has now declined. Depressed MUFs may 
be experienced on 25-Jan due to a possible glancing blow CME 
arrival late in the UT day on 24-Jan. Isolated minor fadeouts 
possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 20 Jan
       Daily Proton Fluence >1 MeV:   3.8E+05
       Daily Proton Fluence >10 MeV:  1.5E+04
       Daily Electron Fluence >2 MeV: 3.10E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 5%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.9

DSCOVR Satellite Solar Wind Day Averaged Data for 20 Jan
Speed: 591 km/sec  Density:    2.6 p/cc  Temp:   218000 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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