[Ips-dsgr] ASWFC Daily Report - 12 April 23 issued 2330 UT on 12 Apr 2023 [SEC=OFFICIAL]

Regional Warning Centre rwc at ips.gov.au
Thu Apr 13 09:30:12 EST 2023


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/12 APRIL 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 12 APRIL AND FORECAST FOR 13 APRIL - 15 APRIL
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 12 Apr:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 12 Apr: 154/109


1B. SOLAR FORECAST
             13 Apr             14 Apr             15 Apr
Activity     R1, chance R2      R1, chance R2      R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   155/109            160/114            165/119

COMMENT: Solar activity on UT day 12-Apr was at the R0 level, 
with several C-class flares. There are currently eight numbered 
sunspot regions visible on the solar disk. AR3272 (S21W09, beta-gamma) 
is the most magnetically complex region and has shown some decay 
in its trailer spots over the UT day. Newly numbered region AR3279 
(S19E61, beta) has recently rotated onto the disk and has exhibited 
growth in its intermediate spots. AR3274 (S07W25, alpha) has 
shown some recent redevelopment of its spots. AR3278 (N13W32, 
beta) has exhibited minor growth but remains unremarkable. All 
other sunspot regions are either stable or in decay. The background 
level of X-ray flux remains at C-class levels. Solar activity 
is expected to be at the R1 level over 13-15 Apr, with a chance 
of R2. Several CMEs were observed, but none are considered geoeffective. 
A filament was observed lifting off the solar disk in H-alpha 
imagery from S40W70 at 12/0057UT. A subsequent CME was observed 
in LASCO C2 coronagraph imagery at 12/0412UT. This CME is not 
considered to contain an Earth-directed component. The solar 
wind speed on UT day 12-Apr was mostly stable, ranging from 325 
to 405 km/s, and is currently near 385 km/s. The peak total interplanetary 
field strength (IMF, Bt) was 10 nT and the north-south IMF component 
(Bz) range was +8 to -4 nT. The solar wind speed may increase 
over 13-15 Apr due to small coronal holes in the northern and 
southern solar hemispheres.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 12 Apr: G0

Estimated Indices 12 Apr : A   K           
   Australian Region       2   11101101
      Cocos Island         2   12110100
      Darwin               3   21111101
      Townsville           3   11102111
      Learmonth            3   12102101
      Alice Springs        1   00101101
      Gingin               2   02201100
      Canberra             1   01001100
      Hobart               1   01101100    

Estimated Antarctic Regional K Indices 12 Apr :
      Macquarie Island    28   44701004
      Casey                6   23321100
      Mawson               3   12211100

Observed Regional daily pc3 Indices 12 Apr : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra            11   (Quiet)
      Hobart              10   (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 12 Apr : A 
           Fredericksburg         5
           Planetary              6                         

Observed AFr/Ap Indices 11 Apr :  A   K
           Fredericksburg         6
           Planetary              5   0131 1111     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
13 Apr    16    G0, slight chance G1
14 Apr    14    G0, slight chance G1
15 Apr    10    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
and Antarctic regions on 12-Apr. G0 geomagnetic conditions are 
expected over 13-15 Apr, with a slight chance of isolated G1 
periods expected over 13-14 Apr due to possible weak CME component 
impacts from recently erupting solar filaments.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
12 Apr      Normal         Normal         Normal         

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
13 Apr      Normal         Normal-fair    Fair
14 Apr      Normal         Normal         Normal-fair
15 Apr      Normal         Normal         Normal-fair

COMMENT: Generally normal HF propagation conditions were observed 
on 12-Apr. Mild degradations at middle to high latitudes are 
possible on 13-14 Apr due to an anticipated mild increase in 
geomagnetic activity, particularly during local night hours. 
Isolated shortwave fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
12 Apr   114

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 20% during local day.
      Enhanced by 55% during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Enhanced by 20% during local night.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
   Southern Australian Region:
      Enhanced by 15% during local day.
      Enhanced by 25% during local night.
      Enhanced by 20% after local dawn.
   Antarctic Region (Casey/Scott Base/Davis/Mawson):
      Enhanced by 15% 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
13 Apr   115    Near to 15% above predicted monthly values
14 Apr   115    Near to 15% above predicted monthly values
15 Apr   115    Near to 15% above predicted monthly values

COMMENT: Maximum usable frequencies (MUFs) on UT day 12-Apr in 
the Australian region were enhanced by 15-25%. Spread F was observed 
during local night hours at Canberra and Hobart. MUFs are expected 
to be near predicted monthly values to 15% enhanced over 13-15 
Apr. Mild degradations are possible during local night hours 
on 13-14 Apr, due to an expected mild increase in geomagnetic 
activity. Isolated shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 11 Apr
       Daily Proton Fluence >1 MeV:   6.0E+04
       Daily Proton Fluence >10 MeV:  2.2E+04
       Daily Electron Fluence >2 MeV: 1.60E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B7.0

DSCOVR Satellite Solar Wind Day Averaged Data for 11 Apr
Speed: 438 km/sec  Density:    7.3 p/cc  Temp:   126000 K  Bz:   2 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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