[Ips-dsgr] ASWFC Daily Report - 30 April 25 issued 2330 UT on 30 Apr 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Thu May 1 09:30:53 AEST 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/30 APRIL 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 30 APRIL AND FORECAST FOR 01 MAY - 03 MAY
STATUS INDICATORS SOL:** YELLOW **   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 30 Apr:  R1

Flares    Max     Fadeout    Freq.  Sectors
  M2.0    0751UT  possible   lower  Mid East/Indian

Observed 10.7 cm flux/Equivalent Sunspot Number for 30 Apr: 148/102


1B. SOLAR FORECAST
             01 May             02 May             03 May
Activity     R1, chance R2      R1, chance R2      R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   150/105            145/99             145/99

COMMENT: Solar activity on UT day 30-Apr was at the R1 level 
due to an M2.0 flare at 30/0751UT produced by AR4079 (N05E50, 
beta-gamma-delta). There are currently five numbered sunspot 
regions visible on the solar disk. AR4079 is the largest and 
most magnetically complex region on the disk. This region has 
exhibited spot development over the UT day, particularly south 
of its main double umbra leader spot. All other sunspot regions 
are either stable or in decay. Solar activity is expected to 
be at the R1 level over 01-03 May, with a chance of R2. No Earth-directed 
CMEs have been observed. The solar wind speed on UT day 30-Apr 
was variable, ranging from 405 to 460 km/s and is currently near 
455 km/s. The peak total interplanetary magnetic field strength 
(IMF, Bt) was 11 nT and the north-south IMF component (Bz) range 
was -7 to +10 nT. The solar wind speed may mildly increase over 
01-02 May due to coronal hole high speed wind stream effects 
from a small northern hemisphere coronal hole. Two additional 
small coronal holes will cross the central meridian today, and 
may influence the solar wind speed on 03-May.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 30 Apr: G0

Estimated Indices 30 Apr : A   K           
   Australian Region       5   22221112
      Cocos Island         5   22221112
      Darwin               6   22221222
      Townsville           8   22231223
      Learmonth            8   32322122
      Alice Springs        7   32231112
      Gingin               6   31221122
      Canberra             5   21221112
      Kennaook Cape Grim   6   21321112
      Hobart               5   21321111    

Estimated Antarctic Regional K Indices 30 Apr :
      Macquarie Island    11   11542001
      Casey                7   23232101
      Mawson              15   44433211

Observed Regional daily pc3 Indices 30 Apr : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             3   (Quiet)
      Hobart              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 30 Apr : A 
           Fredericksburg        11
           Planetary             11                         

Observed AFr/Ap Indices 29 Apr :  A   K
           Fredericksburg         6
           Planetary              6   0222 2122     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
01 May    15    G0, chance of G1
02 May    15    G0, chance of G1
03 May    15    G0, chance of G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 30-Apr. Mostly G0 geomagnetic conditions were 
observed in the Antarctic region, with an isolated period of 
G1 observed at Macquarie Island. G0 geomagnetic conditions are 
expected over 01-03 May, with a chance of G1 due to coronal hole 
high speed wind stream effects.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
30 Apr      Normal         Normal         Normal         

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
01 May      Normal         Normal-fair    Normal-fair
02 May      Normal         Normal-fair    Normal-fair
03 May      Normal         Normal-fair    Normal-fair

COMMENT: HF radio propagation conditions on UT day 30-Apr were 
mostly normal. HF radio propagation conditions are expected to 
be mostly normal over 01-03 May, with fair conditions at middle 
to high latitudes due to 27-day recurrent geomagnetic activity 
patterns. Shortwave fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
30 Apr   119

Observed Australian Regional MUFs
   Cocos Island Region:
      Near predicted monthly values during local day.
      Enhanced by 60% during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Depressed by 20% during local night.
   Northern Australian Region:
      Mostly 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
Mar      126
Apr      115
May      113

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
01 May   115    Near predicted monthly values
02 May   115    Near predicted monthly values
03 May   115    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 42 was issued on 
29 April and is current for 29 Apr to 1 May. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 30-Apr were near predicted 
monthly values. Spread F was observed at Hobart during local 
night hours. MUFs are expected to be near predicted monthly values 
over 01-03 May. Southern Australian region HF conditions may 
become mildly degraded during local night hours over the forecast 
period. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 29 Apr
       Daily Proton Fluence >1 MeV:   6.3E+05
       Daily Proton Fluence >10 MeV:  1.5E+04
       Daily Electron Fluence >2 MeV: 2.40E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.0

DSCOVR Satellite Solar Wind Day Averaged Data for 29 Apr
Speed: 407 km/sec  Density:    5.3 p/cc  Temp:    88300 K  Bz:   3 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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