[Ips-dsgr] ASWFC Daily Report - 07 April 25 issued 2331 UT on 07 Apr 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Tue Apr 8 09:31:40 AEST 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/07 APRIL 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 07 APRIL AND FORECAST FOR 08 APRIL - 10 APRIL
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 07 Apr:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 07 Apr: 162/116


1B. SOLAR FORECAST
             08 Apr             09 Apr             10 Apr
Activity     R0-R1, chance R2   R0-R1, chance R2   R0-R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   160/114            150/105            150/105

COMMENT: Solar activity on UT day 7-Apr was R0, with no significant 
solar flares. There are currently seven numbered sunspot regions 
on the solar disk. AR4048 (S15W46, gamma) has grown; while its 
main leader spot appears to have decayed, several stronger trailer 
spots have developed, and this remains the largest and most unstable 
region on the disk. AR4045 (S13W70, beta), AR4054 (S12W15, beta) 
and AR4055 (N09E11, beta) have all grown, separated and matured. 
Solar activity is expected to be R0-R1 with a chance for R2 over 
8-10 Apr. 

No Earth directed CMEs were observed on UT day 7-Apr. 

S0 solar radiation storm conditions were observed on UT day 7-Apr, 
although a small increased was observed from 1520 UT. The cause 
is not clear, it may be from a farside event or else anomalous 
data, and S0 solar radiation storm conditions are generally expected 
over 8-10 Apr with a chance for S1. 

The solar wind environment on UT day 7-Apr was mildly perturbed. 
The solar wind speed was on a slight decline and ranged from 628 
km/s to 462 km/s, currently near 500 km/s The peak total
 interplanetary field strength (IMF, Bt) was 7 nT and the
 north-south IMF component range (Bz) was +5 to -5 nT. The 
solar wind is expected to be disturbed over 8-10 Apr due to several
 incoming coronal holes, although conditions may fluctuate.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 07 Apr: G0

Estimated Indices 07 Apr : A   K           
   Australian Region       8   22112323
      Cocos Island         7   22112322
      Darwin               9   33111323
      Townsville           9   23112323
      Learmonth           10   32122333
      Alice Springs        7   22111323
      Gingin              12   32122433
      Canberra             7   22112322
      Kennaook Cape Grim   7   2-------
      Hobart               8   22112332    

Estimated Antarctic Regional K Indices 07 Apr :
      Macquarie Island     9   22123332
      Casey               13   43321323
      Mawson              33   45432356

Observed Regional daily pc3 Indices 07 Apr : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin              35   (Quiet to unsettled)
      Canberra            49   (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 07 Apr : A 
           Fredericksburg        11
           Planetary             13                         

Observed AFr/Ap Indices 06 Apr :  A   K
           Fredericksburg        20
           Planetary              0   5323 3333     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
08 Apr    15    G0, chance G1
09 Apr    20    G1, chance G2
10 Apr    15    G0-G1, chance G2

COMMENT: ASWFC Geomagnetic Warning 26 was issued on 6 April and 
is current for 9-10 Apr. G0 geomagnetic conditions were observed 
in the Australian region on UT day 7-Apr. G0-G1 geomagnetic conditions 
were observed in the Antarctic region. G0-G1 geomagnetic conditions 
are possible on 8-Apr late in the day, possibly developing in 
to G2 by 9-Apr. Conditions may fluctuate but G1 periods are also 
expected on 10-Apr due to coronal hole activity.

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

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
08 Apr      Normal         Normal-fair    Normal-fair
09 Apr      Normal         Normal-fair    Normal-fair
10 Apr      Normal-fair    Normal-fair    Normal-fair

COMMENT: HF radio propagation conditions on UT day 7-Apr were 
normal to fair, with degradations in the northern hemisphere. 
HF radio propagation conditions are expected to be normal to 
fair over 8-10 Apr due to persistent coronal hole activity.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
07 Apr   133

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 30% during local day.
      Enhanced by 45% during local night.
   Niue Island Region:
      Enhanced by 25% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Enhanced by 20% during local day.
      Enhanced by 15% during local night.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 30% 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
08 Apr   120    Near predicted monthly values to 15% depressed
09 Apr   120    Near predicted monthly values to 15-20% depressed
10 Apr   115    Near predicted monthly values to 15-20% depressed

COMMENT: Maximum usable frequencies (MUFs) in the Australian 
region on UT day 7-Apr were mostly near predicted values, with 
enhancements in the north and depressions in the south. Spread 
F was observed in Hobart during local night hours. MUFs are expected 
to be near predicted values to 15-20% depressed over 8-10 Apr 
due to persistent coronal hole activity.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 06 Apr
       Daily Proton Fluence >1 MeV:   1.6E+06
       Daily Proton Fluence >10 MeV:  2.5E+04
       Daily Electron Fluence >2 MeV: 2.70E+08   (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:18%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.3

DSCOVR Satellite Solar Wind Day Averaged Data for 06 Apr
Speed: 619 km/sec  Density:    0.2 p/cc  Temp:   246000 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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