[Ips-dsgr] ASWFC Daily Report - 11 April 23 issued 2331 UT on 11 Apr 2023 [SEC=OFFICIAL]
Regional Warning Centre
rwc at ips.gov.au
Wed Apr 12 09:31:10 EST 2023
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/11 APRIL 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 11 APRIL AND FORECAST FOR 12 APRIL - 14 APRIL
STATUS INDICATORS SOL:** YELLOW ** MAG:** YELLOW ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 11 Apr: R1
Flares Max Fadeout Freq. Sectors
M1.3 1016UT possible lower European
Observed 10.7 cm flux/Equivalent Sunspot Number for 11 Apr: 143/97
1B. SOLAR FORECAST
12 Apr 13 Apr 14 Apr
Activity R1,chance R2 R1,chance R2 R1,chance R2
Fadeouts Possible Possible Possible
10.7cm/SSN 145/99 150/105 155/109
COMMENT: Solar activity on UT day 11-Apr was at the R1 level,
due to an M1.3 flare from region AR3272(S21E06, beta-gamma).
This region continued to show a mix of both growth and decay,
though overall appears to be in slow decay. Solar region AR3273(N10E02,
beta) initially showed growth in its intermediate spots then
decay later in the UT day. The spot configuration of the solar
region that recently rotated over the south east solar limb AR3276(S22E64,
beta), was stable. Solar region AR3272 and AR3276 produced numerous
C class flares and AR3273 a single low level C flare. A slowly
declining C5.9 flare was in progress from AR3272 at the time
of writing. There are currently five numbered solar regions on
the disk. Other regions are unremarkable. Solar activity is expected
to be at the R1 level over 12-14 Apr, with a chance of an isolated
R2 event. No significant Earth-directed CMEs have been observed.
The solar wind speed on UT day 11-Apr decreased, ranging from
477 to 378 km/s, and is currently near 378 km/s. The peak total
interplanetary field strength (IMF, Bt) was 9 nT and the north-south
IMF component (Bz) range was +7 to -5 nT. Two small coronal holes
are now visible in the northern and southern solar hemispheres,
near the solar central meridian, at solar latitudes N30 and S35
respectively. These holes may increase solar wind slightly in
coming days but the combination of their small size and moderately
high solar latitude is likely to reduce any effects. A previously
flaring solar region AR3256 (solar latitude S22), which produced
isolated R2 and R3 flares in its previous disk transit, is due
back to the south east limb on 13-Apr. However, confidence is
low for this regions return as the region was showing some decay
in its trailer spots as it rotated over the western solar limb
on 31-Mar, together with the generally exhibited shorter solar
region lifetimes for solar cycle 25.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 11 Apr: G0
Estimated Indices 11 Apr : A K
Australian Region 5 12311111
Cocos Island 3 12211110
Darwin 4 12301111
Townsville 4 12211111
Learmonth 5 12311111
Alice Springs 2 11201011
Gingin 3 02310110
Canberra 2 11211010
Hobart 3 02310011
Estimated Antarctic Regional K Indices 11 Apr :
Macquarie Island 8 33410012
Casey 8 24321111
Mawson 11 13422232
Observed Regional daily pc3 Indices 11 Apr :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 17 (Quiet)
Canberra 11 (Quiet)
Hobart 34 (Quiet to 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 11 Apr : A
Fredericksburg 6
Planetary 6
Observed AFr/Ap Indices 10 Apr : A K
Fredericksburg 11
Planetary 12 3333 3322
2B. MAGNETIC FORECAST
Date Ap Conditions
12 Apr 16 G0, slight chance of G1
13 Apr 16 G0, slight chance of G1
14 Apr 14 G0, slight chance of G1
COMMENT: ASWFC Geomagnetic Warning 17 was issued on 8 April and
is current for 11-12 Apr. G0 geomagnetic conditions were observed
in the Australian and Antarctic region on 11-Apr. Predominately
G0 with the chance of isolated G1 geomagnetic periods are expected
during 12-14 Apr due to possible weak CME component impacts from
a recently erupting solar filaments.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
11 Apr Normal Normal Fair-normal
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
12 Apr Normal Normal Normal-fair
13 Apr Normal Normal-fair Fair
14 Apr Normal Normal Normal-fair
COMMENT: Generally normal HF propagation conditions were observed
on 11-Apr. Mild degradations at middle to high latitudes are
possible on 12-14 Apr due to an anticipated mild increase in
geomagnetic activity, particularly during local night hours.
Isolated shortwave fadeouts are possible.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
11 Apr 119
Observed Australian Regional MUFs
Cocos Island Region:
Enhanced by 40-80% during local day.
Niue Island Region:
Enhanced by 15%
Northern Australian Region:
Enhanced by 15-60%
Southern Australian Region:
Enhanced by 15-25%
Antarctic Region (Casey/Scott Base/Davis/Mawson):
Near predicted monthly values over the UT day.
Monthly T index:
Month T index
Mar 132
Apr 84
May 84
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
12 Apr 130 Near to 15% above predicted monthly values
13 Apr 130 Near to 15% above predicted monthly values
14 Apr 130 Near to 15% above predicted monthly values
COMMENT: ASWFC SWF HF Communications Warning 35 was issued on
10 April and is current for 10-12 Apr. Maximum usable frequencies
(MUFs) on UT day 11-Apr in the Australian region were enhanced
by 15-80%. Stong enhancements were observed at Cocos Island.
Spread F observed during local night hours at Hobart. MUFs are
expected to be near predicted monthly values to 15% enhanced
over 11-13 Apr. Mild degradations are possible during local night
hours on 12-14 Apr, due to expected mild increase in geomagnetic
activity. Isolated shortwave fadeouts are possible.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 10 Apr
Daily Proton Fluence >1 MeV: 4.3E+05
Daily Proton Fluence >10 MeV: 2.2E+04
Daily Electron Fluence >2 MeV: 1.80E+06 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: B7.7
DSCOVR Satellite Solar Wind Day Averaged Data for 10 Apr
Speed: 483 km/sec Density: 11.4 p/cc Temp: 207000 K Bz: 1 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