https://www.facebook.com/296904126846245/

Outbreak Weather, Perth (2025)

24/10/2025

Severe Thunderstorms are Likely This Afternoon and Evening Across Portions of Southeastern WA and Southwestern SA

Scattered severe thunderstorms are expected to develop through the afternoon and evening across parts of southeastern Western Australia into southwestern South Australia. Damaging to locally destructive wind gusts and large to very large hail will be possible.

A closed 500hPa low gradually progress eastward over Western Australia during Friday embedded within more broad westerly zonal flow, a 80 kt jet max is forecast to extend across southwestern WA by 06Z. Ahead of this feature, H300 Heights become broadly diffluent downstream within the WA/SA border region, suggesting that large scale ascent should increase as the day progresses and the trough shifts eastward.

Morning visible/water v***r imagery depicts a surface trough across central southern WA, which is expected to deepen through the day as surface cyclogenesis occurs. By early afternoon, the ECMWF indicates a 998 hPa surface low near the WA/SA border with a developing frontal boundary extending northward. A secondary cold front and associated surface cyclone are evident near the southwest capes of WA.

Persistent convection is ongoing from southern WA into the WA/SA border region, extending north toward Giles, consistent with recent lightning observations.
These storms are occurring within an increasingly moist and unstable airmass, with surface dewpoints near 20 °C expected to advect poleward into the Eucla-Nullarbor region. upstream of this feature a Dryline is is expected to be draped East of Laverton

As a result, MLCAPE of 1000-1500 J/kg is forecast beneath steep mid-level lapse rates (7-7.5°C/km), while 0-6 km bulk shear magnitudes of 50-60 kt will be capable of supporting supercells

A complex convective scenario is expected due to possible residual boundaries from morning convection and several competing Synoptic/mesoscale features which may affect the boundary layer air-mass.
Despite this uncertainty, forecast soundings suggest sufficient buoyancy and deep-layer shear for severe thunderstorms capable of Damaging Wind Gusts and Large Hail supported by steep mid-level lapse rates and favourable CAPE profiles. There is a Slight possibility that Destructive Gusts and Very Large Hail could develop particularly within any supercellular structures that initiate.

Near coastal regions, lower LCL heights and a backed low-level wind field via forecast hodographs (H85 northerlies 35-40 kt) may support a marginal but non-zero tornado threat, if surface-based convection can develop where effective SRH of around 150 ms2/s2 is realised, this scenario is dictated by a small region of lower cloud bases heights and is also conditional to the magnitude of ascent capable of overcoming moderate CINH within the coincident region.

Given Shear Vectors are initially orthogonal to initiating Boundaries, prefrontal Supercell activity appears possible, with possible upscale transition toward MCS complexes during later evening hours as vector orientation becomes more parallel with time, in this scenario Severe Gusts would remain the most probable Hazard.

21/10/2025

A Deepening Mid-Latitude Cyclone is forecast to translate eastward across southern Australia, with surface cyclogenesis expected to occur overnight Tuesday into early Wednesday.
Damaging to Destructive Wind Gusts will be possible in Victoria.

The latest ECMWF guidance indicates a deepening surface cyclone to near 985hPa supported by a strong mid-level trough and prominent jet-streak aloft. As the low intensifies, a tight pressure gradient will develop between the deepening cyclone and a 1020hPa ridge located in Western portions of the country. This will result in a broad area of synoptically driven damaging wind gusts extending across southern Victoria on Wednesday.

Relatively widespread coverage of Damaging straight-line wind gusts of 90-110km/h are likely across Southern Victoria. Some of these wind gusts may be possible of reaching Destructive Gust criteria near 120km/h. The most intense gusts associated with this system are most probable west of Cape Otway and could reach 130km/h.

18/10/2025

WILD Storm Structure from a Supercell near Brisbane this afternoon! This supercell was producing Giant Hail and Destructive Wind Gusts.

📷 Storm report : Casey Mayne
Capture something Storm/Weather related? Send us a message or join our group ! ⬇️
https://www.facebook.com/groups/1130031289124798

18/10/2025

Checkout these these Radar Signatures from the storms near Brisbane, QLD this afternoon!

80dbZ at 400m AGL, well defined hook echo and large inflow region, strengthening Low-level Mesocyclone and a large bounded-weak echo region.
All the Features of Sustained, well developed Left-Moving Cyclonic Supercells!

18/10/2025

VERY DANGEROUS SEVERE THUNDERSTORMS OVER SOUTHEASTERN QLD

A Left moving Supercell is tracking NNE Toward Beaudesert. This Thunderstorm is producing Giant Hailstones (likely at least 5cm) and Destructive Winds. 75dbZ at 800m AGL

18/10/2025

Severe Thunderstorms are likely for parts of NE NSW and SE QLD including the scenic rim.
Isolated to scattered severe thunderstorms are possible on Saturday afternoon across parts of Northeastern NSW and Southeastern QLD. Large to Very Large Hail and Damaging Winds may occur.

A broad high-amplitude mid-tropospheric trough extends across eastern portions of the country, bordered to the west by a large ridge. As the trough traverses eastward, mid level flow assumes a greater meridional flow pattern across eastern QLD and NSW at approximately 40kts, confirmed via morning water v***r imagery.

Surface toughing is positioned NW-SE while a dry-line develops by mid-morning, with a plume of dewpoints reaching 15° east of the dryline, which may be slightly higher near coastal areas. Within this airmass, forecast guidance currently indicates MLCAPE reaching 1000J/kg by afternoon hours.
Surface observations currently suggest a complex forecast scenario with a number of wind shifts noted across the region which may be related to remnant convective boundaries, furthermore most guidance is in agreement with a convergent sea breeze boundary arriving by around 04-06Z.

Despite relatively modest buoyancy and uncertainty regarding convective coverage/intensity, recent CAM runs have suggested an environment supportive of Left-moving supercells with a wide-swathe of 2-5km UH tracks across the region. The ECMWF QPF is broadly consistent with this solution.

In this scenario, storms that initiate within this environment would have the potential to produce Large to Very Large Hail and Damaging Straight-Wind gusts which could reach destructive thresholds, given primarily unidirectional hodographs and sufficient deep layer shear.

16/10/2025

Severe Thunderstorms are likely across parts of Central and Western NSW, the Northern Illawarra, Sydney, Hunter, and Mid-North Coast on Friday.
Large to Very Large Hail and Damaging Wind Gusts will be possible from the afternoon into the evening.

Broad westerly flow associated with a mid to upper-level trough will traverse southeastern Australia through the period, while subtle shortwave perturbations move across eastern NSW.
At the surface, a cold front and surface trough will sweep across southern NSW, with a dryline becoming draped northwest to southeast across central portions of the state.

Strong diurnal heating is expected north of the frontal boundary and surface trough, where surface dewpoints near 15°C will exist beneath a steep mid-level lapse rate plume (around 7.5°C/km). This environment is expected to yield MLCAPE values of 1500J/kg by mid to late afternoon, with effective bulk shear strengthening from 35-40kts to around 45kts during the late afternoon. This setup will support organised convection including supercells.

Supercell development is possible by early to mid-afternoon across parts of Central NSW, with increasing storm coverage spreading eastward toward the coast by late afternoon.
Given elevated composite indices (Significant Hail Parameter), Mid-level temperatures around -15° and a Freezing Level of 2.5km AGL, forecast soundings suggest an environment capable of producing significant hail (5-8cm) and Severe Outflow Gusts, which could reach Destructive criteria particularly with any discrete supercells that develop.

A southeasterly sea-breeze boundary may become convergent near coastal areas during mid-afternoon, providing a focus for storm intensification if sustained supercells interact with this boundary, where low-level moist inflow may be locally enhanced.

11/10/2025

Severe thunderstorms are possible across parts of southeast Queensland and Northeast New South Wales this afternoon and evening.

A surface trough will extend northwest to southeast across Queensland and northern New South Wales, while a dryline develops and becomes draped from the western Darling Downs to Port Macquarie by midday.
Ahead of the dryline, boundary-layer moisture is expected to increase, with surface dew points reaching 16-18°C across parts of the Darling Downs. Richer moisture appears likely to develop within the northeast New South Wales corridor, reaching around 19°C, with a small portion of southeast Queensland possibly also tapping into this moisture plume.

As a result, a narrow corridor of instability is expected to develop, with MUCAPE values near 1500 J/kg, locally higher in northeast New South Wales. Steep low-level lapse rates appear coincident with this axis of instability. In combination with 30-45 knots of 0-6 km deep-layer shear, this suggests the potential for storms capable of producing damaging straight-line wind gusts during the afternoon.

A marginal risk of large hail also exists, particularly across northeast New South Wales. However, relatively borderline mid-level temperatures, dispersed CAPE profiles, and weakly elongated hodographs suggest this is a more conditional threat.

10/10/2025

Golf Ball Sized Hail has been reported near Urunga & Mylestom, NSW this afternoon, after a Left-moving Supercell tracked over the area.

📷 Hail Report: Petal
Capture something Storm/Weather related? Send us a message or join our group ! ⬇️
https://www.facebook.com/groups/1130031289124798

09/10/2025

Severe Thunderstorms are possible across parts of the Darling Downs and NE NSW.

Isolated severe thunderstorms are possible tomorrow afternoon and evening across portions of the Darling Downs, extending southward into northeastern New South Wales.

Current water v***r imagery shows a region of low pressure positioned south of the continent with associated enhanced westerly flow that is forecast to shift eastward during overnight hours.

Radar imagery currently depicts an MCS feature tracking slowly eastward across the Queensland and northeastern New South Wales border regions. This system is primarily non-severe, and 06Z CAM guidance indicates it should exit the region by early morning.

In the wake of this feature, boundary-layer moisture recovery is expected, with surface dewpoints increasing into the 16-19°C range by mid-morning. As a result, MUCAPE values of 1200-1400J/kg are forecast across the Darling Downs, increasing to 2500-3000J/kg across parts of northeastern New South Wales (Grafton to Port Macquarie corridor). Mid-level lapse rates of 7-7.5°C/km will support steepening instability profiles across these regions.

Bulk shear of 35-45 kts across the region will favour organised convection, including the potential for supercell development during the afternoon and evening. Forecast soundings from the western Downs indicate a well mixed boundary layer deepening with time and increasing LCL heights, suggesting damaging straight-line wind gusts and dry microbursts as the primary hazard in that area.

Further south into northeastern New South Wales, forecast hodographs are relatively straight and elongated coinciding with stronger instability and greater CAPE distribution above the HGZ. This environment will favour large to very large hail.
Significant hail (≥5 cm) is possible if discrete supercell organisation occurs.

Some uncertainty remains regarding the influence of residual outflow boundaries and convectively modified air that may exist from the overnight MCS on subsequent storm initiation. Despite this, both ACCESS-C and ECMWF QPF are in reasonable agreement regarding convective timing and spatial coverage.

02/10/2025

Supercells have developed across Queensland's Wide Bay-Burnett region this afternoon. Giant Hail has been produced by numerous storms within the area.
Tennis Ball Sized Hail was reported near Maryborough as a Right Moving Supercell impacted the area.

📷 Hail Reports via: Chantel Braun, Mig Barbara, Julianna Webber

Capture something Storm/Weather related? Send us a message or join our group ! ⬇️
https://www.facebook.com/groups/1130031289124798

30/09/2025

Severe Thunderstorms are possible tomorrow afternoon across portions of the Darling Downs, extending southward into far northeastern New South Wales.

A conditionally unstable environment will exist as a deep, westerly advected mixed layer develops during diurnal heating, characterised by very steep Low-Mid Level lapse rates (>8.5°C/km)
Boundary Layer moisture will remain marginal, with surface dewpoints in the 12–15°C range and mixing ratios around 8 g/kg.

Aloft, broad westerly zonal flow of 45–50 kt associated with two mid-level troughs traversing SA and NSW will support effective bulk shear magnitudes near 40 kts.
Forecast soundings suggest MUCAPE values are expected to reach 1000–1500J/kg, with CINH weakening under diurnal heating.
Previous concerns surrounding ascent within the region and potential for convective initiation are still somewhat unclear, however recent CAM guidance suggests at least isolated initiation is possible between 03–06Z, despite substantial uncertainties in storm coverage further eastward.

Any storms that form are likely to be elevated and may be capable of producing isolated severe outflow gusts and large hail.
The conditional nature of storm initiation keeps confidence in coverage low, however the environment will support a limited corridor of severe potential.
If storms are able to initiate, a northeasterly track appears probable with upscale growth during late afternoon and evening toward coastal areas.

Outbreak Weather

24/10/2025

21/10/2025

18/10/2025

18/10/2025

18/10/2025

18/10/2025

16/10/2025

11/10/2025

10/10/2025

09/10/2025

02/10/2025

30/09/2025

Address

Website

Alerts

Contact The Business

Shortcuts

Share