[Ips-dsgr] ASWFC Daily Report - 23 February 25 issued 2330 UT on 23 Feb 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Mon Feb 24 10:30:49 AEDT 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/23 FEBRUARY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 23 FEBRUARY AND FORECAST FOR 24 FEBRUARY - 26 FEBRUARY
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 23 Feb:  R3

Flares    Max     Fadeout    Freq.  Sectors
  M4.9    0213UT  possible   lower  E. Asia/Aust.
  M1.0    0956UT  possible   lower  Mid East/Indian
  M1.6    1158UT  possible   lower  European
  M1.0    1635UT  possible   lower  South American/
                                    Atlantic
  X2.0    1927UT  probable   all    East Pacific/
                                    North American

Observed 10.7 cm flux/Equivalent Sunspot Number for 23 Feb: 210/161


1B. SOLAR FORECAST
             24 Feb             25 Feb             26 Feb
Activity     R0-R1              R0-R1              R0-R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   210/161            210/161            210/161

COMMENT: Solar activity on UT day 23-Feb was at the R3 level 
due to an X2.0 flare at 23/1927UT. In addition there were four 
M-class flares. An M4.9 flare at 23/0213UT, an M1.0 flare at 
23/0956UT, an M1.6 flare at 23/1158UT and an M1.0 flare at 23/1635UT. 
There are currently nine numbered sunspot regions visible on 
the solar disk. Newly numbered AR4001 (N24W76, beta) was responsible 
for the X2.0 flare and three of the M-class flares on 23-Feb, 
this region has since rotated off the visible solar disk. AR3998 
(S14W25, beta) showed spot development and was responsible for 
the other M-class flare of the UT day. AR4002 (N13E08, beta), 
AR4004 (S14E60, beta) and AR4006 (N17E59, beta) also showed spot 
development on 23-Feb. The largest and most magnetically complex 
region on the solar disk is AR4000 (N18W18, beta-gamma-delta) 
which showed some trailer decay on the UT day but retains a delta 
spot. All other regions are either stable or in decay. Solar 
activity is expected to be at R0-R1 levels over 24-26 Feb. S0 
solar radiation storm conditions were observed on 23-Feb. S0 
conditions are expected on 24-26 Feb, with a chance of S1 on 
24-Feb due to recently rotated off AR4001. No Earth-directed 
CMEs have been observed. A disappearing solar filament is visible 
in H-Alpha, SDO and GOES SUVI imagery at around N41E11 from 23/0649UT. 
No associated CME is visible in available coronagraph imagery. 
An eruption at around N25 off the west limb is visible in GOES 
SUVI and SDO imagery from 23/1927UT, associated with the X2.0 
flare at 23/1927UT. A fast CME is visible in SOHO imagery from 
23/2124UT. Limited images are available at time of writing but 
preliminary modelling suggests this CME will impact Earth at 
1500UT on 25-Feb. More robust analysis will be performed when 
more imagery becomes available. The solar wind speed increased 
slightly on 23-Feb. The wind speed mostly ranged between 290 
km/s and 370 km/s. The current wind speed is around 340 km/s. 
The peak total interplanetary field strength (IMF, Bt) was 13 
nT and the north-south IMF component (Bz) range was +8 to -10 
nT. The solar wind speed is expected to remain near background 
levels on 24-Feb. There is a chance of an increase on 25-Feb 
due to a large coronal hole in the southern hemisphere. A further 
increase is expected on 26-Feb due to high speed wind stream 
effects from an equatorial coronal hole.

-----------------------------------------------------------
2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 23 Feb: G0

Estimated Indices 23 Feb : A   K           
   Australian Region       3   22100002
      Cocos Island         2   22110000
      Darwin               4   22100103
      Townsville           3   22100112
      Learmonth            5   32100003
      Alice Springs        4   22100003
      Gingin               3   22100002
      Canberra             2   12100002
      Kennaook Cape Grim   3   22100002
      Hobart               3   22100002    

Estimated Antarctic Regional K Indices 23 Feb :
      Macquarie Island     2   22100001
      Casey               15   34520123
      Mawson               9   43311112

Observed Regional daily pc3 Indices 23 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 23 Feb : A 
           Fredericksburg         6
           Planetary              6                         

Observed AFr/Ap Indices 22 Feb :  A   K
           Fredericksburg         3
           Planetary              4   2001 2012     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
24 Feb     5    G0
25 Feb    12    G0, chance of G1
26 Feb    16    G0, chance of G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 23-Feb. Mostly G0 conditions were observed in 
the Antarctic region, with a period of G1 observed at Casey. 
G0 geomagnetic conditions are expected on 24-Feb. G0 conditions, 
with a chance of G1 are expected on 25-26 Feb due to anticipated 
coronal hole high speed wind stream effects.

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

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
24 Feb      Normal         Normal         Normal
25 Feb      Normal         Normal         Normal-fair
26 Feb      Normal         Normal-fair    Fair

COMMENT: HF radio propagation conditions were mostly normal on 
23-Feb, with mildly degraded conditions observed at the start 
of the UT day. Mostly normal HF conditions are expected over 
24-26 Feb, with minor degradations possible at high latitudes 
on 26-Feb due to coronal hole high speed wind stream effects. 
Minor shortwave fadeouts are possible.

-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
23 Feb   143

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 20% during local day.
      Enhanced by 40% during local night.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Mostly 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
24 Feb   150    Near to 15% above predicted monthly values
25 Feb   150    Near to 15% above predicted monthly values
26 Feb   150    Near to 15% above predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 24 was issued on 
22 February and is current for 22-24 Feb. Maximum usable frequencies 
(MUFs) on UT day 23-Feb in the Australian region were near predicted 
monthly values. Sporadic E was observed at Townsville during 
local day. MUFs are expected to be near predicted monthly values 
to 15% enhanced over 24-26 Feb. Minor shortwave fadeouts are 
possible.

-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 22 Feb
       Daily Proton Fluence >1 MeV:   1.2E+07
       Daily Proton Fluence >10 MeV:  2.6E+04
       Daily Electron Fluence >2 MeV: 9.90E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 2%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.9

DSCOVR Satellite Solar Wind Day Averaged Data for 22 Feb
Speed: 306 km/sec  Density:    1.7 p/cc  Temp:    34300 K  Bz:   0 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------

Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au



More information about the ips-dsgr mailing list