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

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Sun Jan 26 10:30:53 AEDT 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/25 JANUARY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 25 JANUARY AND FORECAST FOR 26 JANUARY - 28 JANUARY
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 25 Jan:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 25 Jan: 182/135


1B. SOLAR FORECAST
             26 Jan             27 Jan             28 Jan
Activity     R0                 R0                 R0-R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   175/129            170/124            160/114

COMMENT: Solar activity on UT day 25-Jan was R0. Solar region 
AR3961 (S10W73, beta) is approaching the southwest solar limb 
and its trailer spots have now almost completely decayed, with 
the large leader spot remaining mostly stable. Solar region AR3971 
(N12W60, beta) is also in decline. Other regions are small. Solar 
region AR3961 produced several C class flares, the largest a 
C6.6 at 25/0022UT. Solar region AR3971 produced an isolated C 
class flare. New small solar region AR3973 (N19W00, beta) which 
emerged yesterday has slowed in growth. There are currently 8 
numbered regions on the visible solar disk. Solar region AR3959 
which consisted mainly of a large spot has rotated off disk over 
the northwest solar limb. All other sunspot regions are either 
stable or in decay. Solar plasma arch activity on the southeast 
solar limb at solar latitude S20 has reduced over the past 24 
hours. A small area of plasma emission is visible on the northeast 
solar limb at solar latitude N10. Solar activity is expected 
to be R0 over 26-27 Jan and R0-R1 on 28-Jan, with the possible 
return of a previously active region to the northeast limb on 
28-Jan, and a possible new solar region behind the southeast 
limb. S0 solar radiation storm conditions were observed on UT 
day 25-Jan. S0 solar radiation storm conditions are expected 
over 26-28 Jan. No significantly Earth directed CMEs have been 
observed in LASCO or STEREO-A imagery. Several very minor faint 
CMEs to the west were observed in LASCO C2 from late in the UT 
day on 24-Jan and early in the UT day on 25-Jan, possibly associated 
with minor C class flare activity and narrow plasma sprays from 
AR3961, however these minor CMEs were not visible in LASCO C3 
and are considered insignificant due to their faintness, lack 
of propagation and the far western longitude location of AR3961. 
Yesterdays M2.7 flare from AR3961 did not appear to have an associated 
CME of any significance. A coronal hole spanning from the solar 
equator to solar middle latitudes is at solar longitude E45. 
The solar wind on UT day 25-Jan further declined as the recent 
influence of a coronal hole solar wind stream abated. The solar 
wind ranged from 440 to 360 km/s and is currently at 360 km/s. 
The peak total interplanetary field strength (IMF, Bt) was 5 
nT and the north-south IMF component range was +4 to -3 nT. The 
second CME arrival expected for mid to late in the UT day on 
25-Jan has not yet eventuated. The ACE EPAM CME precursor data 
channel has remained flat in the past 24 hours suggesting this 
CME will possibly arrive later than modelled or be a weaker less 
direct impact. Confidence in the arrival of this second CME is 
now reduced.

-----------------------------------------------------------
2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 25 Jan: G0

Estimated Indices 25 Jan : A   K           
   Australian Region       2   11000201
      Cocos Island         1   11010100
      Darwin               2   11101201
      Townsville           3   21101201
      Learmonth            2   11000201
      Alice Springs        1   10000201
      Gingin               2   20000201
      Canberra             1   11000100
      Kennaook Cape Grim   1   11000200
      Hobart               2   11101101    

Estimated Antarctic Regional K Indices 25 Jan :
      Macquarie Island     0   00000100
      Casey               10   23432211
      Mawson               7   23212212

Observed Regional daily pc3 Indices 25 Jan : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin              11   (Quiet)
      Canberra            13   (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 25 Jan : A 
           Fredericksburg         6
           Planetary              9                         

Observed AFr/Ap Indices 24 Jan :  A   K
           Fredericksburg         6
           Planetary              4   1120 1112     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
26 Jan    17    Initially G0, chance G1 later in UT day
27 Jan    17    G1 periods possible early in UT day, then G0
28 Jan     8    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 25-Jan. G0 geomagnetic conditions were observed 
in the Antarctic region. The anticipated arrival of a second 
CME on the UT day on 25-Jan has not eventuated. This CME may 
arrive later and induce weaker geomagnetic activity, with G1 
periods possible from late 26-Jan to early 27-Jan.

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

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
26 Jan      Normal         Normal-fair    Normal-poor
27 Jan      Normal         Fair-normal    Poor-normal
28 Jan      Normal         Normal         Normal

COMMENT: HF radio propagation conditions on UT day 25-Jan were 
generally normal. The anticipated CME arrival on 25-Jan did not 
eventuate, with a weaker/later arrival now expected. HF radio 
propagation conditions are expected to be initially normal on 
25-Jan then becoming mildly degraded for middle to high latitudes 
late in the UT day on 26-Jan and early in the UT day on 27-Jan.

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


Date   T index
25 Jan   137

Observed Australian Regional MUFs
   Cocos Island Region:
      Near predicted monthly values during local day.
      Enhanced by 55% during local night.
   Niue Island Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values.
   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
26 Jan   120    Near predicted monthly values
27 Jan   120    Near predicted monthly values
28 Jan   120    Near predicted monthly values

COMMENT: ASWFC Preliminary HF Communications Warning 12 was issued 
on 23 January and is current for 24-26 Jan. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 25-Jan were near predicted 
monthly values. Mild spread F was observed at Hobart during local 
night hours. Sporadic E was observed at Townsville and Brisbane. 
The CME arrival expected on 25-Jan has not yet eventuated. MUFs 
are expected to be near predicted monthly values. Mildly degraded 
HF conditions may be experienced on 27-Jan if CME induced geomagnetic 
activity eventuates.

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

GOES satellite data for 24 Jan
       Daily Proton Fluence >1 MeV:   8.9E+04
       Daily Proton Fluence >10 MeV:  1.6E+04
       Daily Electron Fluence >2 MeV: 2.80E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C2.3

DSCOVR Satellite Solar Wind Day Averaged Data for 24 Jan
Speed: 451 km/sec  Density:    1.0 p/cc  Temp:    93000 K  Bz:   1 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------

Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au



More information about the ips-dsgr mailing list