[Ips-dsgr] ASWFC Daily Report - 26 February 25 issued 2330 UT on 26 Feb 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Thu Feb 27 10:30:47 AEDT 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/26 FEBRUARY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 26 FEBRUARY AND FORECAST FOR 27 FEBRUARY - 01 MARCH
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 26 Feb:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 26 Feb: 180/133


1B. SOLAR FORECAST
             27 Feb             28 Feb             01 Mar
Activity     R0-R1, chance R2   R0-R1, chance R2   R0-R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   180/133            180/133            175/129

COMMENT: Solar activity on UT day 26-Feb was at the R0 level, 
with several C-class flares. There are currently seven numbered 
sunspot regions visible on the solar disk. No sunspot regions 
showed significant spot development on 26-Feb and there are no 
magnetically complex regions. All sunspot regions are either 
stable or in decay. Solar activity is expected to be at R0-R1 
levels over 27-Feb to 01-Mar, with a chance of R2. S0 solar radiation 
conditions were observed on 26-Feb with the >10MeV proton flux 
elevated below the S1 threshold and in decline. S0 solar radiation 
conditions are expected on 27-Feb to 01-Mar, with a chance of 
S1 on 27-Feb. No geoeffective CMEs were observed on 26-Feb. A 
northeast directed CME was visible in SOHO imagery from 26/0236UT. 
This CME is not considered geoeffective. A disappearing filament 
is visible from 26/0601UT at around S04W23 in H-Alpha, GOES SUVI 
and SDO imagery. An associated faint, west directed CME is visible 
in SOHO and STEREO-A imagery from 26/0658UT. Modelling suggests 
this CME will pass ahead of Earth. An erupting filament is visible 
from 26/1439UT at around S25W60 in H-Alpha, GOES SUVI and SDO 
imagery. An associated southwest directed CME from 26/1512UT 
is visible in SOHO and STEREO-A iamgery. Modelling suggests this 
CME will pass ahead of Earth. The solar wind speed on UT day 
26-Feb increased, with a sharp rise in speed visible at 26/1246UT. 
The wind speed mostly ranged between 330 and 560 km/s and is 
currently near 530 km/s. The peak total interplanetary field 
strength (IMF, Bt) was 20 nT and the north-south IMF component 
(Bz) range was +16 to -9 nT. The solar wind speed is expected 
to be elevated on 27-Feb, with a decline possible in the second 
half of the UT day. An increase in solar wind speed is expected 
on 28-Feb due to a series of coronal holes rotating towards a 
geoeffective position. Elevated solar wind speeds are expected 
on 01-Mar.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 26 Feb: G0

Estimated Indices 26 Feb : A   K           
   Australian Region      12   22323333
      Cocos Island         9   22323222
      Darwin              11   22323332
      Townsville          12   22323333
      Learmonth           13   32323333
      Alice Springs       12   22323333
      Gingin              14   32323433
      Canberra            12   22323333
      Kennaook Cape Grim  12   22323333
      Hobart              12   23322333    

Estimated Antarctic Regional K Indices 26 Feb :
      Macquarie Island    22   23354532
      Casey               25   35543234
      Mawson              17   33434332

Observed Regional daily pc3 Indices 26 Feb : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin              20   (Quiet)
      Canberra            20   (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 26 Feb : A 
           Fredericksburg        15
           Planetary             17                         

Observed AFr/Ap Indices 25 Feb :  A   K
           Fredericksburg        11
           Planetary              8   2111 1233     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
27 Feb    15    G0, chance of G1
28 Feb    20    G0-G1
01 Mar    16    G0-G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 26-Feb. Mostly G1 geomagnetic conditions were 
observed in the Antarctic region. G0 geomagnetic conditions are 
expected on 27-Feb, with a chance of G1 due to ongoing strong 
IMF conditions. G0-G1 geomagnetic conditions are expected on 
28-Feb to 01-Mar due to coronal hole high speed wind stream effects.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
26 Feb      Normal         Normal         Fair           

PCA Event : 10MeV Proton/PCA Event Began at 0010UT 25/02, Ended at 0830UT 25/02

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
27 Feb      Normal         Normal         Normal-fair
28 Feb      Normal         Normal-fair    Fair
01 Mar      Normal         Normal-fair    Fair

COMMENT: HF radio propagation conditions were mostly normal on 
UT day 26-Feb, with fair conditions at high latitudes in the 
southern hemisphere. Mostly normal HF conditions are expected 
on 27-Feb, with a chance of degraded conditions at higher latitudes. 
Normal to fair conditions are expected over 28-Feb to 01-Mar 
due to anticipated geomagnetic activity. Shortwave fadeouts are 
possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
26 Feb   124

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Niue Island Region:
      Mostly near predicted monthly values.
      Depressed by 20% after local dawn.
   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
Jan      124
Feb      118
Mar      115

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
27 Feb   130    Near predicted monthly values
28 Feb   120    Near predicted monthly values
01 Mar   110    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 25 was issued on 
25 February and is current for 25-27 Feb. Maximum usable frequencies 
(MUFs) on UT day 26-Feb in the Australian region were near predicted 
monthly values. MUFs are expected to be near predicted monthly 
values over 27-Feb to 01-Mar. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 25 Feb
       Daily Proton Fluence >1 MeV:   1.9E+07
       Daily Proton Fluence >10 MeV:  1.0E+06
       Daily Electron Fluence >2 MeV: 1.20E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C2.8

DSCOVR Satellite Solar Wind Day Averaged Data for 25 Feb
Speed: 372 km/sec  Density:    6.1 p/cc  Temp:    48700 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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