Alerts:
Space Weather Message Code: ALTEF3
Serial Number: 3677
Issue Time: 2026 Apr 16 1323 UTC
CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3676
Begin Time: 2026 Apr 03 0920 UTC
Yesterday Maximum 2MeV Flux: 3248 pfu
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.
Space Weather Message Code: WATA30
Serial Number: 271
Issue Time: 2026 Apr 15 2143 UTC
WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
Apr 16: None (Below G1) Apr 17: G2 (Moderate) Apr 18: G2 (Moderate)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.
Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.
Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.
Radio - HF (high frequency) radio propagation can fade at higher latitudes.
Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
Solar-terrestrial indices for 16 April follow.
Solar flux 108 and estimated planetary A-index 4.
The estimated planetary K-index at 2100 UTC on 16 April was 1.00.
No space weather storms were observed for the past 24 hours.
Space weather for the next 24 hours is predicted to be moderate.
Geomagnetic storms reaching the G2 level are likely.
Geo Magnetic Forecast:
NOAA Ap Index Forecast
Observed Ap 14 Apr 004
Estimated Ap 15 Apr 005
Predicted Ap 16 Apr-18 Apr 008-020-040
NOAA Geomagnetic Activity Probabilities 16 Apr-18 Apr
Active 25/15/10
Minor storm 05/30/35
Moderate storm 01/35/35
Strong-Extreme storm 01/20/20
NOAA Kp index forecast 16 Apr - 18 Apr
Apr 16 Apr 17 Apr 18
00-03UT 1.67 2.33 6.00
03-06UT 2.67 2.67 6.00
06-09UT 2.67 2.67 5.00
09-12UT 2.33 2.00 4.00
12-15UT 1.67 1.33 3.67
15-18UT 1.67 2.67 3.33
18-21UT 1.67 4.33 3.00
21-00UT 2.33 5.67 4.33
Extended Three Day Forecast:
A. NOAA Geomagnetic Activity Observation and Forecast
The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 16-Apr 18 2026 is 6.00 (NOAA Scale
G2).
NOAA Kp index breakdown Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
00-03UT 0.67 2.33 6.00 (G2)
03-06UT 1.00 2.67 6.00 (G2)
06-09UT 1.00 2.67 5.00 (G1)
09-12UT 0.67 2.00 4.00
12-15UT 1.67 1.33 3.67
15-18UT 1.67 2.67 3.33
18-21UT 1.67 4.33 3.00
21-00UT 2.33 5.67 (G2) 4.33
Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are likely on 17-18
Apr due to the anticipated arrival of a negative polarity CH HSS CIR.
B. NOAA Solar Radiation Activity Observation and Forecast
Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.
Solar Radiation Storm Forecast for Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.
C. NOAA Radio Blackout Activity and Forecast
No radio blackouts were observed over the past 24 hours.
Radio Blackout Forecast for Apr 16-Apr 18 2026
Apr 16 Apr 17 Apr 18
R1-R2 30% 30% 30%
R3 or greater 5% 5% 5%
Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
through 18 Apr, mostly due to the flare potential of Region 4419.
Extended Space Weather Discussion:
Solar Activity
.24 hr Summary...
Solar activity reached low levels with only B and C-class flaring from
Region 4419 (N13E36, Eki/beta-gamma). Moderate growth occurred in Region
4419 along with consolidation of its leading spots. Slight decay was
observed in Region 4416 (N20W57, Dao/beta).
Other activity included two CMEs on the NE and SE quadrants. The first
was associated with a long-duration B7.9 flare that started at 15/0730
UTC from Region 4419. A likely associated CME was observed off the NE
limb at 15/0748 UTC. The second was an approximate 35 degree filament
eruption, centered near S30E20, at 15/0940 UTC. An associated CME was
observed off the SE limb at 15/1036 UTC. Initial modelling indicated no
Earth-directed component. A partial halo CME was observed with the bulk
off the NW limb beginning at 15/1148 UTC. That CME was determined to be
backsided. An additional CME was observed off the West limb starting in
C2 imagery near 16/0000 UTC. This CME was also determined to originate
from the far side of the disk.
.Forecast...
Solar activity is expected to be low with a chance for M-class (R1-R2,
Minor-Moderate) flare on 16-18 Apr primarily due to the flare potential
of Region 4419.
Energetic Particle
.24 hr Summary...
Electrons greater than 2 MeV at geosynchronous orbit reached high levels
with a peak of 3,248 pfu observed at 15/1820 UTC. The greater than 10
MeV proton flux was at background levels.
.Forecast...
The greater than 2 MeV electron flux is expected to reach high levels on
16-17 Apr. A brief drop to moderate levels is expected on 18 Apr with
the arrival of a negative polarity CH HSS. The greater than 10 MeV
proton flux is expected to continue at background levels on 16-18 Apr.
Solar Wind
.24 hr Summary...
Solar wind parameters were at nominal levels with solar wind speed
ranging from 324-381 km/s. Total field ranged from 2-6 nT while the Bz
component was between +4/-5 nT. Phi angle was predominantly positive.
.Forecast...
Solar wind parameters are expected to become enhanced by mid to late on
17 Apr with the arrival of a co-rotating interaction region followed by
negative polarity CH HSS activity. Solar wind speed ranging from 600-700
km/s are likely based on recurrent values. Enhanced conditions are
expected to persist through 18 Apr.
Geospace
.24 hr Summary...
The geomagnetic field was quiet.
.Forecast...
The geomagnetic field is expected to be quiet to unsettled on 16 Apr. By
mid to late on 17 Apr, CH HSS activity is expected to cause unsettled to
active periods with G1-G2 (Minor-Moderate) geomagnetic storming likely.
Unsettled to G2 (Moderate) levels are expected to continue through 18
Apr as HSS effects persist.
27 Day Forecast:
Date | Radio Flux | Planetary A Index | Largest Kp Index
2026 Apr 13 95 8 3
2026 Apr 14 90 8 3
2026 Apr 15 100 12 3
2026 Apr 16 105 8 3
2026 Apr 17 110 5 2
2026 Apr 18 110 15 3
2026 Apr 19 110 20 4
2026 Apr 20 120 12 4
2026 Apr 21 130 10 3
2026 Apr 22 140 8 3
2026 Apr 23 145 5 2
2026 Apr 24 145 8 3
2026 Apr 25 140 12 4
2026 Apr 26 140 10 3
2026 Apr 27 140 5 2
2026 Apr 28 140 5 2
2026 Apr 29 135 20 5
2026 Apr 30 130 18 5
2026 May 01 125 12 4
2026 May 02 125 10 3
2026 May 03 115 8 3
2026 May 04 108 8 3
2026 May 05 105 5 2
2026 May 06 100 5 2
2026 May 07 95 20 4
2026 May 08 90 15 3
2026 May 09 90 8 3
v4.16b
v4.X Release 17th Dec 2020)
Fixed New GOES and HPI inputs from noaa for Json (17/12/20).
Addded the ability to add 2 custom Magnetometers in settings (comming soon) (18/10/19).
Improved Hobart Magnetometer code. (18/18/19)
Move all presets into their own pop out side menu. (19/06/19)
Added Composite weather maps (TAS, VIC and SA), thanks to Oz forecast! (19/06/19)
UI Upgrades, Name, Logo and Website Site Changes.
Added custom line widths for most items.
Added GOES Difference (#1 - #2)
Added Ovation-prime model outputs.
v3.8x
Various Updates, New AF Index Algo. (8/12/18)
v3.6x
Added more Presets. Disabled Presets overwriting graph views (6/7/18)
Added GeoSpace Kp Model Prediction. (3/7/18)
Added SWPC Kp Forecast + Observation. (2/7/18)
Removed WingKP and USKp. :( No longer Avaliable. (2/7/18)
Removed feed from www.dunedinaurora.nz (Unreliable). (2/7/18)
Updates to latest JQuery, JQuery Mobile and AmCharts etc. (2/7/18)
Enhanced Pro setting with Dynamic Preasure. (2/7/18)
Added Quickselect preset buttons to main page. (2/7/18)
v3.5x
Added Ruru Observatory Magnetometer. (25/4/28)
Added Forecast Sub Tabset. (1/3/18)
Added Extended Discussion Text, 27Day FC (1/3/18)
Removed Dial, and Added Forecast Report. (28/2/18)
Updated A few settings for better visilation. (28/2/18)
Updated Goes-13 is Now Goes-14 (15/2/18)
Improved Commmunity Activity for faster loads.
Consolidated Proton Density / Dynamic Preasure.
Added Additional Balloon Text.
Added TAFS Visual Probability in %.
User Interface Upgrades.
Add 'Dial' for the basics, with default support.
Added one click presets.
v2.1 - v2.49
Added 'Automatic Chart Update' option in settings.
Database caching enabled, significant load time improvements.
Extension to max 96 hours of data, up from 24.
Added ACE Bt,Bx and By for comparison.
Added More User Presets.
Fixed Orentation Change Alert.
Small layout changes.
Added Header Image.
Removed Top Header to fee up Space, Refresh added to Chart Tab.
Added Community Activity Indicator
Fixed MAG value issues in graph.
Added Second Hobart MAG Source.
Updated Comment Features (Disable).
v2.0
Fixed DSCOVR B? display bug.
Added MAG Stack Feature.
Upgrade to json feeds.
Feeds are timezone and forecast aware, making them super fast.
DB Optimisation, improved DB search times.
Charts are now zoomable, allow selection and export.
Added USAF Kp, Updated Wing Kp.
Added Ovation Aurora Short Term Forecast.
Added Macquarie Island MAG feed.
Added Mawson MAG Feed.
Added Canberra Feed.
Added MAG feed from www.dunedinaurora.nz (Portobello).
Added Brendan's experemental MAG feed (Hobart).
Fixed cookie bug, One Alert is enough for landscape mode.
> v1.0 (Started 20/10/2014)
Mawson and Macquarie Island data is copyright Commonwealth of Australia (Geoscience Australia), and redistributed under Creative Commons v4.
Thanks to INTERMAGNET for promoting high standards of magnetic observatory practice in providing access to these feeds. (www.intermagnet.org).
Local Australian weather composite maps provided by Oz Forecast