[Ips-dsgr] ASWFC Daily Report - 26 February 23 issued 2330 UT on 26 Feb 2023 [SEC=OFFICIAL]

Regional Warning Centre rwc at ips.gov.au
Mon Feb 27 10:30:54 EST 2023


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/26 FEBRUARY 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 26 FEBRUARY AND FORECAST FOR 27 FEBRUARY - 01 MARCH
STATUS INDICATORS SOL:** YELLOW **   MAG:** RED **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 26 Feb:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 26 Feb: 159/113


1B. SOLAR FORECAST
             27 Feb             28 Feb             01 Mar
Activity     R0-R1              R0-R1              R0-R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   155/109            150/105            150/105

COMMENT: Solar activity on UT day 26-Feb was at R0 levels. There 
are currently 6 numbered sunspot regions on the solar disk. AR3229 
(N26W58, beta), which has been producing long duration flares 
and fast CMEs, has been decaying. AR3234 (N30W05, beta-delta) 
and AR3236 (S26W16, beta-gamma) have shown unstable growth, but 
have not yet produced any significant flares. All other sunspot 
regions are stable. Solar activity is expected to be at R0-R1 
levels over 27-Feb to 1-Mar. No new geoeffective CMEs have been 
observed. The solar wind speed on UT day 26-Feb was variable 
and ranged between 424 to 671 km/s, and is currently near 670 
km/s. A moderate shock was observed in the solar wind at 1843UT 
on 26 Feb, indicating the CME first observed on 24/2036UT is 
arriving and increased geomagnetic activity is expected. The 
peak interplanetary field strength (IMF, Bt) reached 21 nT and 
the north-south IMF component (Bz) range was +9 to -18 nT. Bz 
was southward since 26/1900UT, soon after the solar wind shock, 
until 26/2150UT. An equatorial coronal hole is currently in a 
geoeffective location and is expecting to further increase the 
solar wind speed over 27-28 Feb. The solar wind speed may decrease 
by 1-Mar. Two solar flares from AR3229 on 24/2030UT and 25/1940UT 
enhanced the solar energetic proton flux and caused S1 conditions 
since 25/2110UT. Further S1 conditions are not likely, unless 
further solar flaring from AR3229 is observed.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 26 Feb: G2

Estimated Indices 26 Feb : A   K           
   Australian Region      21   33333155
      Cocos Island        17   32323145
      Darwin              16   33333144
      Townsville          16   33333144
      Learmonth           23   43333255
      Alice Springs       21   33333155
      Gingin              30   42333266
      Canberra            15   33332144
      Hobart              18   33332145    

Estimated Antarctic Regional K Indices 26 Feb :
      Macquarie Island    16   33343134
      Casey               31   45443355
      Mawson              40   34543257

Observed Regional daily pc3 Indices 26 Feb : 
      Darwin               0   (Quiet)
      Townsville           2   (Quiet)
      Learmonth           15   (Quiet)
      Alice Springs        2   (Quiet)
      Gingin              80   (Active)
      Canberra            91   (Minor storm)
      Hobart             103   (Major storm)

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 26 Feb : A 
           Fredericksburg        17
           Planetary             22                         

Observed AFr/Ap Indices 25 Feb :  A   K
           Fredericksburg         9
           Planetary             10   1122 1433     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
27 Feb    36    G1-G2, chance of isolated periods of G3
28 Feb    20    G1-G2
01 Mar    14    G0, chance of isolated periods of G1

COMMENT: ASWFC Geomagnetic Warning 8 was issued on 26 February 
and is current for 26-28 Feb. Mostly G0-G1 geomagnetic conditions 
were observed in the Australian region on UT day 26-Feb, with 
two periods of G2 at Gingin. Mostly G0-G1 geomagnetic conditions 
were observed in Antarctica, with an isolated period of G3 at 
Mawson. G1-G2 geomagnetic conditions, with a chance of an isolated 
period of G3, are expected over 27-28 Feb due to anticipated 
geomagnetic activity. In the BOM magnetometer data for 26 Feb, 
a weak (21nT) impulse was observed at 1923UT, indicating the 
arrival of a CME first observed on 24/2036UT. An equatorial coronal 
hole is currently in a geoeffective location and is expected 
to further increase geomagnetic activity over 27-28 Feb. A second 
CME that was first observed 25/1938UT is expected to impact Earth 
around 27/2100UT ± 7 hours and produce G1, chance of G2 conditions 
on 28-Feb. Mostly G0 conditions are expected on 1-Mar, with possible 
isolated periods of G1.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
26 Feb      Normal         Normal-fair    Poor(PCA)      

PCA Event : 10MeV Proton/PCA Event Began at 2100UT 25-Feb, and has been
fluctuating between
10 pfu (the S1 threshold) since 1910 26-Feb. 


3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
27 Feb      Normal-fair    Fair           Fair-poor
28 Feb      Normal-fair    Fair           Fair-poor
01 Mar      Normal-fair    Fair-normal    Fair

COMMENT: Degraded HF conditions may be expected on 27-Feb, due 
to PCA from an S1 event that began at 25/2110UT, particularly 
in high latitude regions. Further degraded HF conditions are 
expected over 27-Feb to 1-Mar due to geomagnetic activity. Shortwave 
fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
26 Feb   135

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 15% during local day.
      Enhanced by 35% during local night.
      Enhanced by 95% after local dawn.
   Niue Island Region:
      Near predicted monthly values during local day.
      Enhanced by 30% during local night.
      Enhanced by 20% after local dawn.
   Northern Australian Region:
      Enhanced by 25% during local day.
      Enhanced by 40% during local night.
      Enhanced by 30% after local dawn.
   Southern Australian Region:
      Enhanced by 25% during local day.
      Enhanced by 20% during local night.
   Antarctic Region (Casey/Scott Base/Davis/Mawson):
      Enhanced by 15% over the UT day.

Monthly T index:
Month  T index
Jan      119
Feb      75
Mar      76

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
27 Feb    60    Near predicted monthly values to 20% depressed
28 Feb    60    Near predicted monthly values to 20% depressed
01 Mar    75    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 22 was issued on 
24 February and is current for 25-27 Feb. ASWFC HF Communications 
Warning 23 was issued on 26 February and is current for 27-28 
Feb. Maximum usable frequencies (MUFs) in the Australian region 
on UT day 26-Feb were mostly 20-30% enhanced, and enhancements 
of up to 40% were observed in the northern Australian region 
during local night. Sporadic-E was briefly observed in most sites 
during local dawn. MUFs are expected to return to monthly expected 
values, with possible depressions up to 20%, due to geomagnetic 
activity over 27-Feb to 1-Mar. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 25 Feb
       Daily Proton Fluence >1 MeV:   1.0E+07
       Daily Proton Fluence >10 MeV:  4.5E+05
       Daily Electron Fluence >2 MeV: 2.10E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.0

DSCOVR Satellite Solar Wind Day Averaged Data for 25 Feb
Speed: 416 km/sec  Density:    6.5 p/cc  Temp:    81800 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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