[Ips-dsgr] ASWFC Daily Report - 01 April 25 issued 2330 UT on 01 Apr 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Wed Apr 2 10:30:56 AEDT 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/01 APRIL 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 01 APRIL AND FORECAST FOR 02 APRIL - 04 APRIL
STATUS INDICATORS SOL:** RED **   MAG:** YELLOW **     ION: ** YELLOW **
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 01 Apr:  R2

Flares    Max     Fadeout    Freq.  Sectors
  M5.6    0646UT  possible   lower  Mid East/Indian
  M2.5    2231UT  possible   lower  East Pacific/
                                    North American

Observed 10.7 cm flux/Equivalent Sunspot Number for 01 Apr: 182/135


1B. SOLAR FORECAST
             02 Apr             03 Apr             04 Apr
Activity     R1-R2,chance R3    R1-R2,chance R3    R1-R2,chance R3
Fadeouts     Probable           Probable           Probable
10.7cm/SSN   180/133            176/130            176/130

COMMENT: Solar activity on UT day 01-Apr was R2 due to an M5.6 
flare from AR4046 (N05E20, beta-gamma). The flare was from an 
area southeast of the regions single large spot. This region 
has recently been flare quiet and also produced the R3 flare 
back on 28-Mar. This region has been largely stable with a reduction 
in penumbral area south of the single large spot and a reduction 
in its very small trailer spots. Large solar region AR4048 (S15E44, 
beta-gamma) produced an M2.5 R1 flare and has grown in longitudinal 
extent with an increase in leader spot umbral area and general 
increase in penumbral area. Smaller regions AR4044 (N17W14, beta) 
and AR4049 (S31E19, beta) have shown slight growth and produced 
minor C flare activity. Other regions are small and are either 
stable or in decay. There are currently seven numbered sunspot 
regions on the solar disk. Solar flare activity is expected to 
be R1-R2 over 02-04 Apr. There is a chance for an isolated R3 
flare. No Earth-directed CMEs were observed in available imagery. 
An eastward directed far side CME was observed from 01/1824UT. 
S2 solar radiation storm conditions were observed on 02-Apr with 
the solar proton flux now declining. The solar proton flux is 
possibly from the recent east limb X1 flare on 28-Mar. S1 declining 
to S0 conditions are expected on 02-Apr and S0 conditions are 
expected on 03-Apr. The solar wind environment on UT day 01-Apr 
was steady but variable with a possible very weak indistinct 
CME signature observed at 01/1730UT with the total field becoming 
subsequently slightly enhanced and a slight increase in speed 
was then also observed. The solar wind speed ranged from 473 
to 353 km/s and is currently near 430 km/s. The peak total interplanetary 
field strength (IMF, Bt) was 15 nT and the north-south IMF component 
range (Bz) was +9 to -6 nT. The solar wind speed is expected 
to be slightly enhanced today and may decline on 03-Apr. A small 
equatorial coronal hole is now just past solar central meridian 
and is smaller on this solar rotation. An moderate increase in 
solar wind speed is expected over 04-06 Apr from this hole.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 01 Apr: G0

Estimated Indices 01 Apr : A   K           
   Australian Region       3   11201021
      Cocos Island         3   12201020
      Darwin               5   23211021
      Townsville           5   11212122
      Learmonth            5   21311121
      Alice Springs        3   11201021
      Gingin               4   11301121
      Canberra             2   01101012
      Kennaook Cape Grim   2   11101011
      Hobart               2   11101011    

Estimated Antarctic Regional K Indices 01 Apr :
      Macquarie Island     0   00000011
      Casey               17   34433233
      Mawson              10   31312323

Observed Regional daily pc3 Indices 01 Apr : 
      Darwin               8   (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 01 Apr : A 
           Fredericksburg         5
           Planetary              6                         

Observed AFr/Ap Indices 31 Mar :  A   K
           Fredericksburg         8
           Planetary              9   1122 2332     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
02 Apr     8    G0
03 Apr    10    G0
04 Apr    17    G0-G1

COMMENT: ASWFC Geomagnetic Warning 24 was issued on 1 April and 
is current for 4-5 Apr. G0 geomagnetic conditions were observed 
in the Australian and Antarctic region on UT day 01-Apr. G0 geomagnetic 
conditions are exected over 02-03 Apr, with G0-G1 conditions 
over 04-05 Apr due to a wind stream from a small equatorial coronal 
hole.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
01 Apr      Normal         Normal         Poor-fair      

PCA Event : 10MeV Proton/PCA Event Began 31/1425UT and is in progress

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
02 Apr      Normal         Normal         Poor-fair
03 Apr      Normal         Normal         Normal-fair
04 Apr      Normal         Normal-fair    Fair

COMMENT: HF radio propagation conditions were mostly normal on 
UT day 01-Apr for low to middle latitudes, with a solar radiation 
storm increasing absorption by up to 2.5db at polar latitudes. 
This S2-Moderate event has now declined to S1-Minor and is expected 
to end today. Antarctic Riometers observed a peak absorption 
of 2.0-2.5db during the interval 01/0300-0900UT. HF conditions 
at other latitudes are expected to be generally normal. Shortwave 
fadeouts are expected.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
01 Apr   152

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 25% during local day.
      Enhanced by 65% during local night.
   Niue Island Region:
      Enhanced by 30% during local day.
      Enhanced by 20% 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 during local day.
      Enhanced by 20% during local night.
      Enhanced by 20% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.
      Proton event in progress, increased absorption observed.

Monthly T index:
Month  T index
Mar      126
Apr      115
May      113

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
02 Apr   140    About 15% above predicted monthly values
03 Apr   140    About 15% above predicted monthly values
04 Apr   140    About 15% above predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 33 was issued on 
31 March and is current for 1-3 Apr. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 01-Apr were near predicted 
values to 25% enhanced. Ionospheric equatorial scintillation 
was observed at Weipa during the interval 01/1105-1120UT. A shortwave 
fadeout was observed 01/0639-0701UT. MUFs are generally expected 
to be near predicted values to 15% enhanced over 02-04 Apr. Shortwave 
fadeouts are expected on daylight HF circuits.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 31 Mar
       Daily Proton Fluence >1 MeV:   8.1E+06
       Daily Proton Fluence >10 MeV:  1.5E+06
       Daily Electron Fluence >2 MeV: 1.10E+08   (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:11%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.4

DSCOVR Satellite Solar Wind Day Averaged Data for 31 Mar
Speed: 443 km/sec  Density:    1.1 p/cc  Temp:    57300 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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