[Ips-dsgr] ASWFC Daily Report - 25 February 24 issued 2330 UT on 25 Feb 2024 [SEC=OFFICIAL]

Regional Warning Centre rwc at ips.gov.au
Mon Feb 26 10:30:56 EST 2024


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/25 FEBRUARY 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 25 FEBRUARY AND FORECAST FOR 26 FEBRUARY - 28 FEBRUARY
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 25 Feb:  R1

Flares    Max     Fadeout    Freq.  Sectors
  M2.0    1722UT  possible   lower  South American/
                                    Atlantic

Observed 10.7 cm flux/Equivalent Sunspot Number for 25 Feb: 181/134


1B. SOLAR FORECAST
             26 Feb             27 Feb             28 Feb
Activity     R1-R2              R1-R2              R1-R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   180/133            175/129            175/129

COMMENT: Solar activity on UT day 25-Feb was at the R1 level 
due to an M2.0 flare at 25/1722UT from AR3590 (N17W13, gamma-delta). 
There are currently six numbered sunspot regions visible on the 
solar disk. AR3590 remains the largest and most magnetically 
complex region on the solar disk. This region showed mild decay 
in its trailer spots and some growth in its leading spots over 
the UT day. Newly numbered AR3595 (N20E48, beta-gamma) recently 
appeared on the solar disk and has exhibited spot development. 
All other sunspot regions are either stable or in decay. Solar 
activity is expected to be at R1-R2 levels over 26-28 Feb. Several 
CMEs were observed, but none are considered geoeffective. Multiple 
low velocity CMEs were observed from the western limb, but are 
not considered to be Earth-directed. The solar wind speed on 
UT day 25-Feb was mostly stable, ranging from 355 to 450 km/s 
and is currently near 395 km/s. The peak total interplanetary 
field strength (IMF, Bt) was 14 nT and the north south IMF component 
(Bz) range was +12 to -10 nT. Several short periods of southward 
IMF conditions were observed throughout the UT day. The solar 
wind speed is expected to remain mildly elevated over 26-28 Feb 
due to coronal hole high speed wind stream effects from a small 
southern hemisphere coronal hole.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 25 Feb: G0

Estimated Indices 25 Feb : A   K           
   Australian Region       9   22223133
      Cocos Island         -   --------
      Darwin              10   32223133
      Townsville          10   22323133
      Learmonth           10   23223133
      Alice Springs       10   22323133
      Gingin               8   22222133
      Canberra             8   23222123
      Hobart               9   23232123    

Estimated Antarctic Regional K Indices 25 Feb :
      Macquarie Island    15   23254222
      Casey               19   45432223
      Mawson              20   45443222

Observed Regional daily pc3 Indices 25 Feb : 
      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 25 Feb : A 
           Fredericksburg        11
           Planetary             12                         

Observed AFr/Ap Indices 24 Feb :  A   K
           Fredericksburg         6
           Planetary              4   1001 2222     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
26 Feb    16    G0, chance of G1
27 Feb     8    G0
28 Feb     6    G0

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 25-Feb. G0-G1 geomagnetic conditions were observed 
in the Antarctic region. G0 geomagnetic conditions are expected 
over 26-28 Feb, with a chance of G1 on 26-Feb due to the combined 
effects of a recent CME arrival and coronal hole high speed wind 
stream effects.

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

PCA Event : No event.

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

COMMENT: HF radio communication conditions on UT day 25-Feb were 
mostly normal. HF radio communication conditions are expected 
to be mostly normal over 26-28 Feb. Shortwave fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
25 Feb   126

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

Monthly T index:
Month  T index
Jan      144
Feb      108
Mar      108

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
26 Feb   115    Near predicted monthly values
27 Feb   115    Near predicted monthly values
28 Feb   115    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 22 was issued on 
25 February and is current for 25-27 Feb. Maximum usable frequencies 
(MUFs) on UT day 25-Feb were near predicted monthly values to 
20% enhanced in the Australian region. Depressions of up to 25% 
have been observed after local dawn in the southern Australian 
region. Sporadic E was observed during local night hours at Hobart. 
Ionospheric scintillation was observed 25/1133-1150UT at Weipa. 
MUFs are expected to be near predicted monthly values over 26-28 
Feb. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 24 Feb
       Daily Proton Fluence >1 MeV:   3.3E+06
       Daily Proton Fluence >10 MeV:  2.4E+04
       Daily Electron Fluence >2 MeV: 9.70E+05   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.6

DSCOVR Satellite Solar Wind Day Averaged Data for 24 Feb
Speed: 339 km/sec  Density:    2.8 p/cc  Temp:    60000 K  Bz:   0 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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