[Ips-dsgr] ASWFC Daily Report - 18 February 25 issued 2330 UT on 18 Feb 2025 [SEC=OFFICIAL]
Australian Space Weather Forecasting Centre
aswfc at bom.gov.au
Wed Feb 19 10:30:49 AEDT 2025
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/18 FEBRUARY 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 18 FEBRUARY AND FORECAST FOR 19 FEBRUARY - 21 FEBRUARY
STATUS INDICATORS SOL:** YELLOW ** MAG:GREEN ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 18 Feb: R0
Flares: none.
Observed 10.7 cm flux/Equivalent Sunspot Number for 18 Feb: 178/131
1B. SOLAR FORECAST
19 Feb 20 Feb 21 Feb
Activity R0-R1 R0-R1 R0-R1
Fadeouts Possible Possible Possible
10.7cm/SSN 180/133 180/133 185/138
COMMENT: Solar activity on UT day 18-Feb was at the R0 level,
with several C-class flares observed. There are currently nine
numbered sunspot regions visible on the solar disk. AR3996 (S17E24,
beta-gamma) and AR3998 (S14E45, beta-delta) both displayed spot
development over the UT day. There are currently no large and
complex regions with significant flaring history on the solar
disk. All other sunspot regions are either stable or in decay.
Solar activity is expected to be at R0-R1 levels over 19-21 Feb.
S0 solar radiation storm conditions were observed on 18-Feb.
S0 conditions are expected on 19-21 Feb. No Earth-directed CMEs
have been observed. A partial filament lift off is visible in
SDO, GOES SUVI and H-Alpha imagery from 18/0051UT at around S16E17.
A significant amount of the filament remains on the disk and
there is no associated CME visible in coronagraph imagery. The
solar wind speed on UT day 18-Feb was steady, mostly ranging
between 420 and 540 km/s and is currently near 490 km/s. The
peak total interplanetary field strength (IMF, Bt) was 10 nT
and the north-south IMF component (Bz) range was +9 to -9 nT.
A sustained period of significant -Bz began at around 18/1940UT
and is ongoing at time of writing. The solar wind speed is expected
to slowly decline over 19-21 Feb due to waning coronal hole high
speed wind stream effects.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 18 Feb: G0
Estimated Indices 18 Feb : A K
Australian Region 10 33211323
Cocos Island 8 33211213
Darwin 9 33211313
Townsville 11 33311323
Learmonth 10 33211323
Alice Springs 11 33311323
Gingin 10 33211323
Canberra 9 33210323
Kennaook Cape Grim 9 33210323
Hobart 9 33210323
Estimated Antarctic Regional K Indices 18 Feb :
Macquarie Island 9 33200323
Casey 24 45522334
Mawson 31 44412327
Observed Regional daily pc3 Indices 18 Feb :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 4 (Quiet)
Canberra 19 (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 18 Feb : A
Fredericksburg 10
Planetary 11
Observed AFr/Ap Indices 17 Feb : A K
Fredericksburg 11
Planetary 12 2312 3423
2B. MAGNETIC FORECAST
Date Ap Conditions
19 Feb 15 G0, chance G1
20 Feb 5 G0
21 Feb 5 G0
COMMENT: G0 geomagnetic conditions were observed in the Australian
region on UT day 18-Feb. G1-G2 geomagnetic conditions were observed
in the Antarctic region. G0 geomagnetic conditions are expected
over 19-21 Feb, with a chance of G1 on 19-Feb due to ongoing
coronal hole high speed wind stream effects.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
18 Feb Normal Normal Fair-normal
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
19 Feb Normal Normal Normal-fair
20 Feb Normal Normal Normal
21 Feb Normal Normal Normal
COMMENT: HF radio propagation conditions were mostly normal on
18-Feb, with some degraded conditions at the start of the UT
day, mostly at high latitudes and in the southern hemisphere.
Mostly normal HF conditions are expected over 19-21 Feb. Shortwave
fadeouts are possible.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
18 Feb 146
Observed Australian Regional MUFs
Cocos Island Region:
Enhanced by 25% during local day.
Enhanced by 60% during local night.
Niue Island Region:
Enhanced by 20% during local day.
Enhanced by 25% during local night.
Northern Australian Region:
Near predicted monthly values during local day.
Enhanced by 30% during local night.
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
19 Feb 140 Near to 15% above predicted monthly values
20 Feb 150 Near to 15% above predicted monthly values
21 Feb 150 Near to 15% above predicted monthly values
COMMENT: Maximum usable frequencies (MUFs) on UT day 17-Feb in
the Australian region were near predicted monthly values with
enhancements of up to 30% observed in the northern Australian
region. Spread F and sporadic E were observed at Hobart during
local night hours. MUFs are expected to be near predicted monthly
values to 15% enhanced over 19-21 Feb. Shortwave fadeouts are
possible.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 17 Feb
Daily Proton Fluence >1 MeV: 5.0E+05
Daily Proton Fluence >10 MeV: 1.7E+04
Daily Electron Fluence >2 MeV: 9.50E+07 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:10%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: C1.2
DSCOVR Satellite Solar Wind Day Averaged Data for 17 Feb
Speed: 496 km/sec Density: 0.9 p/cc Temp: 151000 K Bz: -2 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