[Ips-dsgr] ASWFC Daily Report - 22 May 26 issued 2330 UT on 22 May 2026 [SEC=OFFICIAL]

Sat May 23 09:30:48 AEST 2026

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/22 MAY 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 22 MAY AND FORECAST FOR 23 MAY - 25 MAY
STATUS INDICATORS SOL:** YELLOW **   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 22 May:  R1

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 22 May: 124/77

1B. SOLAR FORECAST
             23 May             24 May             25 May
Activity     R0, chance of R1   R0, chance of R1   R0, chance of R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   125/78             125/78             130/84

COMMENT: Solar flare activity on UT day 22-May was at the R1 
level, with a M2.3 flare observed at 22/1029UT. There are currently 
five numbered sunspot regions and one unnumbered visible on the 
solar disk. The largest flare of the UT day was attributed to 
AR4436 recently rotated off the NW limb. AR4441 (N08W52, beta-gamma) 
showed some spot development. AR4444 (S19E55, beta) and AR4443 
(S16W04, beta) both showed development in their leader spots 
over the UT day, AR4441 is the largest and most magnetically 
complex. Unnamed AR (N05W066, beta) has recently rotated onto 
the visible disk. All other sunspot regions are either stable 
or in decay. Solar flare activity is expected to be at the R0 
level over 23-25 May, with a chance of R1. S0 solar radiation 
conditions were observed on UT day 22-May. S0 solar radiation 
conditions are expected over 23-25 May. No Earth-directed coronal 
mass ejections (CMEs) were observed on 22-May. A northwest-directed 
CME was observed in LASCO C2 coronagraph imagery at 22/1048UT. 
Modelling indicates this CME is not geoeffective. The solar wind 
speed decreased over 22-May. The speed ranged from 350 to 430 
km/s and is currently near 370 km/s. The peak total interplanetary 
magnetic field strength (IMF, Bt) was 8 nT and the north-south 
IMF component (Bz) range was -4 to +5 nT. The solar wind speed 
is expected to remain at background levels over 23-25 May.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 22 May: G0

Estimated Indices 22 May : A   K           
   Australian Region       3   12220001
      Cocos Island         2   12110001
      Darwin               3   12220011
      Townsville           4   22220012
      Learmonth            5   12320012
      Alice Springs        3   02220001
      Gingin               3   12220011
      Canberra             3   12220001
      Kennaook Cape Grim   4   12230001
      Hobart               4   12230101    

Estimated Antarctic Regional K Indices 22 May :
      Macquarie Island     4   01140000
      Casey                9   33321122
      Mawson              17   34332125

Observed Regional daily pc3 Indices 22 May : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (Quiet)
      Hobart               0   (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 22 May : A 
           Fredericksburg         5
           Planetary              6                         

Observed AFr/Ap Indices 21 May :  A   K
           Fredericksburg         6
           Planetary              7   3211 212-     

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
23 May     5    G0
24 May     4    G0
25 May     4    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
and Antarctic regions on UT day 22-May. G0 geomagnetic conditions 
are expected over 23-25 May.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
22 May      Normal         Normal         Normal-fair    

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
23 May      Normal         Normal         Normal
24 May      Normal         Normal         Normal
25 May      Normal         Normal         Normal

COMMENT: Global ionospheric conditions were fair to normal over 
UT day 22-May, with degradations mostly observed in the northern 
hemisphere in the first third of the UT day. Mostly normal HF 
propagation conditions are expected over 23-25 May.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
22 May    59

Observed Australian Regional MUFs
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Near predicted monthly values during local day.
      Depressed by 15% during local night.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 20% during local night.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Depressed by 20% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Enhanced by 15% over the UT day.

Monthly T index:
Month  T index
Apr      74
May      71
Jun      68

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
23 May    55    Near predicted monthly values
24 May    55    Near predicted monthly values
25 May    55    Near predicted monthly values

COMMENT: Maximum Usable Frequencies (MUFs) on UT day were depressed 
by up to 20% during local night hours in the northern and southern 
Australian region. Spread-F was observed at Hobart and Canberra 
during local night hours. MUFs are expected to be near predicted 
monthly values over 23-25 May.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 21 May
       Daily Proton Fluence >1 MeV:   1.2E+06
       Daily Proton Fluence >10 MeV:  1.9E+04
       Daily Electron Fluence >2 MeV: 1.30E+08   (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:12%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B5.8

DSCOVR Satellite Solar Wind Day Averaged Data for 21 May
Speed: 431 km/sec  Density:    1.5 p/cc  Temp:    58500 K  Bz:  -1 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