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

Sat Feb 22 10:30:54 AEDT 2025

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

Flares    Max     Fadeout    Freq.  Sectors
  M3.3    1215UT  possible   lower  European
  M1.4    1435UT  possible   lower  South American/
                                    Atlantic

Observed 10.7 cm flux/Equivalent Sunspot Number for 21 Feb: 197/149

1B. SOLAR FORECAST
             22 Feb             23 Feb             24 Feb
Activity     R0-R1              R0-R1              R0-R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   195/147            190/143            185/138

COMMENT: Solar activity on UT day 21-Feb was at the R1 level, 
due to an M3.3 flare at 21/1215UT and an M1.4 flare at 21/1435UT. 
There are currently seven numbered sunspot regions visible on 
the solar disk and two unnumbered regions. Newly numbered AR4000 
(N18E10, beta-gamma-delta) was responsible for both of the M-class 
flares over the UT day. AR4000 and AR3998 (S14E05, beta-gamma-delta) 
both showed significant spot development on 21-Feb and have delta 
spot candidates. All other numbered regions are either stable 
or in decay. An unnumbered region has developed at N29W70 and 
another unnumbered region has rotated on to the solar disk at 
N13E61, both with beta magnetic characteristics. Solar activity 
is expected to be at R0-R1 levels over 22-24 Feb. S0 solar radiation 
storm conditions were observed on 21-Feb, with a very slight 
increase in >10MeV proton flux observed from 21/1800UT. S0 conditions 
are expected on 22-24 Feb. No Earth-directed CMEs have been observed. 
A disappearing filament is visible in H-Alpha, GOES SUVI and 
SDO imagery from 21/0403UT at around S33E20. No associated CME 
is visible in available coronagraph imagery. A west directed 
CME is visible from 21/1248UT in SOHO and STEREO-A imagery. This 
event is associated with an eruption on the solar disk at around 
N25 on the western limb, visible in SDO and GOES SUVI imagery 
from 21/1155UT. Modelling indicates this CME will pass ahead 
of the Earth. The solar wind speed on UT day 21-Feb declined, 
mostly ranging between 290 and 405 km/s and is currently near 
305 km/s. The peak total interplanetary field strength (IMF, 
Bt) was 6 nT and the north-south IMF component (Bz) range was 
+4 to -4 nT. The solar wind speed is expected to remain near 
background levels over 22-24 Feb.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 21 Feb: G0

Estimated Indices 21 Feb : A   K           
   Australian Region       2   11102001
      Cocos Island         1   11110000
      Darwin               2   21101001
      Townsville           2   20102011
      Learmonth            3   22102002
      Alice Springs        2   10102002
      Gingin               3   21102002
      Canberra             2   11102001
      Kennaook Cape Grim   2   11102001
      Hobart               2   11102001    

Estimated Antarctic Regional K Indices 21 Feb :
      Macquarie Island     2   10003001
      Casey               10   33422012
      Mawson               9   43221122

Observed Regional daily pc3 Indices 21 Feb : 
      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 21 Feb : A 
           Fredericksburg         6
           Planetary              6                         

Observed AFr/Ap Indices 20 Feb :  A   K
           Fredericksburg         5
           Planetary              2   4311 1001   

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
22 Feb     5    G0
23 Feb     5    G0
24 Feb     8    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
and Antarctic regions on UT day 21-Feb. G0 geomagnetic conditions 
are expected over 22-24 Feb.

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

PCA Event : No event.

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

COMMENT: HF radio propagation conditions were fair to normal 
on 21-Feb, with mildly degraded conditions observed at the start 
and end of the UT day. Mostly normal HF conditions are expected 
over 22-24 Feb.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
21 Feb   154

Observed Australian Regional MUFs
   Cocos Island Region:
      Mostly near predicted monthly values.
   Niue Island Region:
      Enhanced by 30% during local day.
      Enhanced by 35% during local night.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 25% during local night.
   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
Jan      124
Feb      118
Mar      115

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
22 Feb   150    Near to 15% above predicted monthly values
23 Feb   150    Near to 15% above predicted monthly values
24 Feb   150    Near to 15% above predicted monthly values

COMMENT: Maximum usable frequencies (MUFs) on UT day 21-Feb in 
the Australian region were near predicted monthly values, with 
enhancements of up to 25% observed in the northern Australian 
region. Mild spread F was observed during local night hours at 
Hobart. MUFs are expected to be near predicted monthly values 
to 15% enhanced over 22-24 Feb.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 20 Feb
       Daily Proton Fluence >1 MeV:   4.5E+04
       Daily Proton Fluence >10 MeV:  1.6E+04
       Daily Electron Fluence >2 MeV: 9.20E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 2%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.2

DSCOVR Satellite Solar Wind Day Averaged Data for 20 Feb
Speed: 473 km/sec  Density:    7.3 p/cc  Temp:   313000 K  Bz:   2 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