[Ips-dsgr] ASWFC Daily Report - 25 December 24 issued 2330 UT on 25 Dec 2024 [SEC=OFFICIAL]
Australian Space Weather Forecasting Centre
aswfc at bom.gov.au
Thu Dec 26 10:30:49 AEDT 2024
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/25 DECEMBER 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 25 DECEMBER AND FORECAST FOR 26 DECEMBER - 28 DECEMBER
STATUS INDICATORS SOL:** RED ** MAG:** YELLOW ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 25 Dec: R1
Flares Max Fadeout Freq. Sectors
M1.2 24/2234UT possible lower East Pacific/
North American
M2.8 0430UT possible lower E. Asia/Aust.
M4.9 0449UT possible lower E. Asia/Aust.
Observed 10.7 cm flux/Equivalent Sunspot Number for 25 Dec: 253/203
1B. SOLAR FORECAST
26 Dec 27 Dec 28 Dec
Activity R1-R2, chance R3 R1-R2, chance R3 R1-R2, chance R3
Fadeouts Probable Probable Probable
10.7cm/SSN 250/200 250/200 255/205
COMMENT: Solar activity on UT day 25-Dec was at the R1 level
due to an M2.9 flare at 25/0430UT and an M4.9 flare at 25/0449UT.
There were eleven numbered active sunspot regions visible on
the solar disk on 25-Dec. AR3938 (N19E51, beta-gamma) and AR3932
(S17E01, beta-gamma-delta) were responsible for the two M-class
flares of the UT day. These two regions, along with AR3928 (S12W17,
beta-gamma) and AR3933 (S08W14, beta-delta) are the most magnetically
complex regions on the solar disk. Only AR3938 showed development
over the UT day. All other active regions were either stable
or in decline. Solar activity is expected to be at R1-R2 levels,
with a chance of R3 flaring over 26-28 Dec. S0 solar radiation
storm conditions were observed on UT day 24-Dec, however the
>10 MeV proton flux as measured at GOES was elevated but in decline
over the UT day. S0 solar radiation storm conditions, with a
chance of S1 are expected over 26-28 Dec. Several CMEs were observed
on 25-Dec, however all are considered to be far side events and
thus, not geoeffective. The solar wind speed was in decline over
the UT day, ranging between 415 and 550 km/s. The solar wind
speed is currently at around 435 km/s. The peak total interplanetary
field strength (IMF, Bt) was 6 nT and the north-south IMF component
range (Bz) was +4 to -5 nT. An enhancement in the solar wind
environment is expected in the first half of 26-Dec due to an
anticipated impact from a CME first observed on 23-Dec. The solar
wind speed is expected to be elevated over 26-27 Dec, and in
decline on 28-Dec.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 25 Dec: G0
Estimated Indices 25 Dec : A K
Australian Region 5 23221011
Cocos Island 3 22220001
Darwin 6 23221012
Townsville 6 23221112
Learmonth 5 23221101
Alice Springs 4 22221001
Gingin 4 22221011
Canberra 4 23220000
Kennaook Cape Grim 5 23320010
Hobart 5 23320010
Estimated Antarctic Regional K Indices 25 Dec :
Macquarie Island 4 23220000
Casey 27 36642121
Mawson 17 44432133
Observed Regional daily pc3 Indices 25 Dec :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 12 (Quiet)
Canberra 2 (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 25 Dec : A
Fredericksburg 7
Planetary 8
Observed AFr/Ap Indices 24 Dec : A K
Fredericksburg 9
Planetary 8 2210 3323
2B. MAGNETIC FORECAST
Date Ap Conditions
26 Dec 18 G1, chance of G2
27 Dec 12 G0, chance of G1
28 Dec 8 G0
COMMENT: ASWFC Geomagnetic Warning 77 was issued on 25 December
and is current for 25-26 Dec. G0 geomagnetic conditions were
observed in the Australian region on UT day 25-Dec. Mostly G0
conditions were observed in the Antarctic region, with G2 conditions
observed at Casey. A CME, first observed on 23-Dec is expected
to arrive early on 26-Dec and induce G1 geomagnetic conditions,
with a chance of G2. G0 conditions, with a chance of G1 are expected
on 27-Dec and G0 conditions are expected on 28-Dec.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
25 Dec Normal Normal Normal-fair
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
26 Dec Normal Normal-fair Fair
27 Dec Normal Normal Normal-fair
28 Dec Normal Normal Normal-fair
COMMENT: HF radio propagation conditions on UT day 25-Dec were
mostly normal, with degradations at high latitudes mostly in
the second half of the UT day. HF radio propagation conditions
are expected to be mildly degraded on 26-Dec due to anticipated
geomagnetic activity. The strongest degradations are expected
at high latitudes. Conditions are expected to be mostly normal
on 27-28 Dec. Shortwave fadeouts are probable.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
25 Dec 141
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values.
Niue Island Region:
Near predicted monthly values during local day.
Enhanced by 25% during local night.
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
Nov 127
Dec 117
Jan 114
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
26 Dec 110 Near predicted monthly values
27 Dec 120 Near predicted monthly values
28 Dec 135 Near predicted monthly values
COMMENT: ASWFC SWF HF Communications Warning 148 was issued on
23 December and is current for 24-26 Dec. Maximum usable frequencies
(MUFs) in the Australian region on UT day 25-Dec were near predicted
values. Sporadic-E was observed during local night hours at Hobart,
Canberra and Brisbane. MUFs are expected to be near predicted
values to depressed by 10-15% on 26-Dec due to anticipated geomagnetic
activity. Depressions may continue into 27-Dec but MUFs are expected
to be near predicted monthly values by 28-Dec. Shortwave fadeouts
are probable.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 24 Dec
Daily Proton Fluence >1 MeV: 5.5E+05
Daily Proton Fluence >10 MeV: 1.5E+05
Daily Electron Fluence >2 MeV: 2.70E+07 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: C3.1
DSCOVR Satellite Solar Wind Day Averaged Data for 24 Dec
Speed: 555 km/sec Density: 1.5 p/cc Temp: 215000 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