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8 07, 2019

What are Altostratus Clouds?

2019-07-08T02:22:08+10:00

Altostratus clouds are some of the most dull and boring clouds across the sky. This type of cloud is quite layered and featureless, with a grey colouring. The Latin words album and stratus mean spread out or flattened with height.. which is exactly what these clouds are, medium to high flat and dull clouds. 

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Altostratus clouds are very large, mid level thin sheets and are usually composed of a mixture of water droplets and ice crystals. They typically don’t produce precipitation. They are thin enough that the sun can seep through them, but they often retain a grey colouring with no identifiable structural features about them. 

They form when cirrostratus clouds descend from much higher altitudes in the sky, and while theres nothing special about these clouds they can help produce optical phenomenon’s such as iridescence and coronas. Due to their featureless appearance, there are no categories that this cloud fits into, it essentially is its own cloud. There are some different patterns though that may occur and these include undulatus, radiatus and duplicatus. 

Altocumulus clouds often form ahead of frontal systems, mostly occluded fronts but sometimes cold fronts. As the front passes through, altostratus layers deepens and bulk out to become nimbostratus clouds which can produce rain or snow. This can typically mean that the visual sighting of these clouds refers to a change in the weather over the next 12-24 hours.

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What are Altostratus Clouds?2019-07-08T02:22:08+10:00
8 07, 2019

What are Altocumulus Clouds?

2019-07-08T02:17:04+10:00

Altocumulus clouds are small clouds situated in the mid levels of the atmosphere, between roughly 7,000 and 18,000ft. These small clouds are called cloudlets, which are mostly shaped like rounded clumps. Altocumulus clouds are made up of a combination of both ice and water which allows them to have a slightly ethereal appearance compared to those of the cumulus variety which are slightly bigger in size and fluffier in appearance. 

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Altocumulus clouds can form through several different methods. In all of these methods, they produce a key visual difference which allows them to be differentiated from cirrocumulus clouds. That key visual is the presence of shading, as the clouds appear to retain a ‘greyer’ colouring around their base. This is largely due to their elevation, where the cirrocumulus clouds are higher in the atmosphere and the sun is rarely “above” them, but also shining light below them… the altocumulus clouds may be lower than the sun in comparison to the horizon and thus the sun’s light doesn’t project across the entirety of the cloud. They can form through the break up of altostratus clouds. They can also form through the lifting process of moist air pockets which become cooled by mountainous terrain, this process can produce atmospheric waves which can produce the clouds. 

While the weather is generally fairly tame when altocumulus clouds are present, they can on the off occasion produce precipitation. This precipitation won’t touch the ground though as its evaporated before it touches the ground, this precipitation is called virga.

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Altocumulus clouds are categorised into 4 different types and while their mechanics are similar they all have their own unique characteristics which help determine which is which. These categories are Stratiformis, Lenticularis, Castellanus, Floccus.

  • Altocumulus Stratiformis: These are the most common types of altocumulus cloud. They are flat-bottomed puffy clouds, packed tightly together but separated by small rivers of sky. These can sometimes cover the entire sky.

  • Altocumulus Lenticularis: These are arguably the most spectacular cloud, out of all the cloud types possible. Altocumulus Lenticularis clouds, also known as lenticular clouds, are lens-shaped clouds that form over hilly or mountainous terrain and are often referred to as ‘UFO’ clouds or ‘spaceship’ clouds due to their appearance. 

  • Altocumulus Castellanus: These are great indicators of instability in a localised area, as Altocumulus Castellanus towers can often lead to the formation of cumulonimbus clouds or thunderstorms. These are much taller clouds than they are wide, but they retain a puffy appearance. 

  • Altocumulus Floccus: These are often spotted alongside altocumulus castellanus clouds, however they are slightly smaller and more ragged cloudlets. These are often found with virga present also.

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    Altocumulus stratiformis via Frank Le Blanq

     

     

What are Altocumulus Clouds?2019-07-08T02:17:04+10:00
7 07, 2019

What are Cirrostratus Clouds?

2019-07-07T21:36:27+10:00

Cirrostratus clouds are high altitude clouds that are mostly transparent. They cover large areas of the sky which can sometimes lead to the formation of sun or moon halos (also known as a 22 degree halo). The appearance of a 22 degree halo may be the only indication that the clouds are even present due to how transparent and thin they become. The latin words cirrus and stratus mean lock or tuft and flattened / spread out which is exactly what these clouds look like – spread out locks of hair covering the sky. 

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Cirrostratus clouds typically sit no lower than 20,000ft in the atmosphere and can reach as high as 40,000ft. They from as a result of slowly rising air. They are usually generated at the forefront of frontal weather systems such as warm fronts and cold fronts and the movement of the clouds can be used to predict the weather over the next 24 hours. Cirrostratus clouds are also closely linked to vapour contrails as planes fly through the dry atmosphere. 

While cirrostratus clouds don’t typically produce any weather themselves, they are fantastic indicators of approaching weather. There are 2 different forms or categories of cirrostratus clouds. (1) Cirrostratus Nebulous which likely indicates that an incoming front will likely produce persistent rain within 24 hours or (2) Cirrostratus Fibratus which likely indicates that stratus clouds may proceed it and produce precipitation (most likely in the form of light drizzle or rain). Cirrostratus clouds can span for thousands of kilometres and due to their transparent appearance, the sun is able to shine through them but at the same time, they can be slightly dense enough to still cast shadows on the Earth’s surface. 

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Cirrostratus Clouds with the sun reflecting through via Stephen Burt

 

What are Cirrostratus Clouds?2019-07-07T21:36:27+10:00
7 07, 2019

What are Nimbostratus Clouds?

2019-07-07T21:27:35+10:00

If you thought altostratus clouds were dull and boring, wait for nimbostratus clouds. These are considered the most dull and boring of the cloud types. Nimbostratus clouds are essentially extensive dark or grey, gloomy, featureless layers of thick cloud that block out the sun and produce persistent rain. There is nothing picturesque about them at all, the only thing one could argue is that altostratus clouds are more dull because they don’t produce precipitation whereas nimbostratus at least produces rain. 

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These clouds typically sit quite low in the atmosphere, around the 2,000-10,000ft mark. The lower they are, the more likely they are to produce heavier rainfall, however rainfall or precipitation (whether its snow, rain or any other form) is likely regardless. These clouds by definition are mid-level clouds as they predominantly sit closer to the 10,000ft however as stated above, they can fall to as low as 2,000ft which is matching it with some of the lowest clouds in the atmosphere. 

Nimbostratus clouds form through the deepening and thickening of an altostratus cloud and is often associated with frontal systems, similarly to the altostratus cloud. Nimbostratus clouds will often bring precipitation that can last for several hours – whether its rainfall or snowfall, until the associated passes over. The only precipitation this cloud doesn’t produce is hail. If hail is present then by definition it becomes a cumulonimbus cloud. 

Similarly to the altostratus cloud, nimbostratus clouds aren’t categorised into seperate groups like most of the other clouds. 

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What are Nimbostratus Clouds?2019-07-07T21:27:35+10:00
7 07, 2019

What are Stratocumulus Clouds?

2019-07-07T21:21:00+10:00

Stratocumulus clouds are the most common cloud on planet Earth. They are essential low level, clumps or patches of cloud which vary in colour from bright white to dark and dull grey. These common clouds are recognised with their defined bases, some of which are darker than others. They usually have gaps between to signify their individuality but its not uncommon for them to become joined together. 

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Stratocumulus clouds typically form from status clouds breaking up. They are indicators of a change in weather and are usually present near any type of frontal system (cold, warm or occluded). While these clouds are typically fairly dull on the weather front, they can produce showery conditions. These unsettled conditions however are usually due to other clouds being present with the stratocumulus clouds, not the stratocumulus clouds themselves. In reality, they rarely produce anything more than drizzle. 

Stratocumulus clouds are categories into 4 seperate groups, while the mechanics that make up stratocumulus clouds are the same for each group.. their are slight differences that help determine which is which. These include Stratiformis, Cumulogenitus, Lenticularis and Castellanus. 

Stratocumulus lenticularis via jim Galvin

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  • Stratocumulus Stratiformis: These are the most common of the common and are basically flat based layers of cloud with a few cracks between each individual cloud.

  • Stratocumulus Cumulogenitus: These typically occur when cumulus clouds encounter a temperature inversion which suppresses their development and growth from transitioning between cumulus and cumulonimbus. These then spread outwards and clump together.

  • Stratocumulus Castellanus: These are a much thicker and much more drizzly type of stratocumulus cloud. Turreted tops form when convection initiates through the stable layer and allows the stratocumulus to extend upwards. This can potentially lead to the formation of cumulus congestus or even cumulonimbus thunderstorm clouds.

  • Stratocumulus Lenticularis: These are the rarest of the stratocumulus family and are often spotted around hilly or mountainous terrain. They have a very different appearance to the far more spectacular lenticular cloud. They form when hills or mountains produce atmospheric waves which then contribute to their lens-shaped appearance.

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    Stratocumulus Castellanus via Barry Chan

What are Stratocumulus Clouds?2019-07-07T21:21:00+10:00
7 07, 2019

What are Stratus Clouds?

2019-07-07T21:01:05+10:00

These are the lowest clouds on average across the entire globe, ranging anywhere from 1,200ft to the surface (0ft). These are quite layered clouds and are fairly uniformed grey or white colour. They are often last long periods of time and are often the scene of dull and overcast days. When they near or reach the surface (0ft) they are what we commonly consider fog or mist. 

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Stratus clouds form in calm and very stable conditions where gentle breezes raise cool and moist air over the colder land or ocean surfaces. These clouds can exist in a variety thicknesses and are sometimes opaque enough to darken the day and allow for as little light as possible to come through.

Stratus clouds are usually accompanied by next to no rainfall, however if they are thick enough they can produce light drizzle. This drizzle can also fall in the form of snow if its cold enough. 

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Stratus clouds are only defined by two different categories. The first being stratus nebulous which is a featureless dark layer, capable of producing drizzle. The second is stratus fractus, this is a straight layer which is starting to break up or dissipate and this is where the breaks in cloud being to appear.

Stratus Undulats – Not a very common type of stratus cloud that has some gaps allowing light to penetrate through, as well as some undulations in the cloud formation. Image via Martin Gudd

 

What are Stratus Clouds?2019-07-07T21:01:05+10:00
21 06, 2019

Honouring A Legacy For The Ages: Dale Sharpe, DK Photography

2019-06-21T17:03:13+10:00

While we as friends of Dale, and the community as supporters of Dale, grieve for his early and all too soon departure of this life. Its important for us to cherish and pay homage to this amazing man’s work. Its fair to say that the photography world will forever have an irreplaceable hole, left by Dale, due to his simply phenomenal eye for detail, and his energy to strive for literal perfection in a near impossible environment to achieve such feats. The amazing thing is, even though it was nearly impossible… he defied the odds time and time again, producing masterpieces that all of us, even his closest friends, were left stunned and wanting more.

Arguably the greatest of loves from Dale, outside of his family and friends, was his love of storms. He traveled often all around Australia seeking out not just the most intense moments of mother nature, but also the most graceful and photogenic moments – often creating perfection out of nearly nothing. Dale often travelled across South East QLD and North East NSW for storms, but also ventured in Inland NSW, Inland QLD, rural South Australia and Southern Western Australia where his love of crops, dead trees, lakes and storms as a combination was maximised. Even if we could’ve shared every single photo posted by Dale, it wouldn’t give his work justice as he had hundreds of photos sitting and waiting to be posted for every single one that was posted. His love for storms took him to the pinnacle of storm chasing, tornado alley, where he captured scene you could only dream of. Using the words “perfection”, “amazing”, “masterpiece”, don’t do it justice. But here are some of his works of art that took the world by storm.

Russel Springs, Kansas, USA

McAllastar, Kansas, USA

Byron Bay, NSW, Australia

Goondiwindi, QLD, Australia

The Wheatbelt, WA, Australia

Brisbane, QLD, Australia

While it may not have been his greatest of loves, his work with Iceland and the Northern Lights was arguably his greatest work. He had an ability to capture magic and this lead to the production of some tours which he hosted several times per year across the island. He did several tours across the latter part of the calendar year and the start of the New Year which were often sold out many months in advance – not just because people wanted to go, but they wanted to go with the best of the best. This is where he wowed the world by proposing to his fiancee and good friend of ours, Karlie, with the shot of a lifetime. It wasn’t just the aurora either. Dale found so much beauty across the region, with countless waterfalls and sunsets that would leave you breathless.

The Proposal.

Akranes, Iceland

Kirkjufellsfoss, Iceland

Reine, Norway

Hamnoy, Lofoten, Norway

Kirkjufellfoss, Iceland

Flakstadoya, Norway

Outside of his love of the aurora, and thunderstorms, he honestly just loved getting out, going for a drive and finding somewhere to photograph across Australia, or even hopping on a plane and heading to New Zealand, Patagonia, Iceland, Norway, the United States… or where ever his heart desired. Whether it was unique, or a common photography hunting ground where he challenged himself to add the “Dale twist”, the final product MADE you WANT to go there and see it for yourself. This included landmarks, astrophotography, waterfalls, valleys, canyons – you name it. All we can do is marvel at some of his final pieces.

Spa Pool, Hammersley Gorge, WA.

The Pinnacles, Western Australia

Horseshoe Bend, Arizona

Church of Good Shepherd, New Zealand

Horse Head Rock, NSW

Narrabri, NSW

Dale, and Karlie as a combination of DK Photography, MASTERED several avenues of the photography world. One of these avenues was the art of Wedding Photography. Their wedding photos were graceful, they were peaceful. You could feel the love gushing out of the photos that were presented. They captured moments you could only dream of getting on that special day. Its for this reason, they were often booked out weekend after weekend after weekend to do weddings.

 

HSC’s own Jeff & Sara photographed on their special day by Dale & Karlie

 

It would be easy to share another 200 photos and be just as amazed every single time. At the end of the day though, this man – a father, a loving partner, a son and a friend to so many, was taken way too soon, in the prime of his career and life. We are all extremely hurt and extremely saddened by his parting, but at the same time we are all so very honoured and privileged to have known him, chased with him, found wisdom and guidance from him and even shared a meal with him. He was a man who lit up the room as soon as he walked through the door – a door that was always open in everyone’s home for him and Karlie. His work and legacy needs to be appreciated for eternity because not only was he a legend and true master of his craft, but we may never get the privilege of knowing someone even remotely close to his ability and caring nature again. 

Honouring A Legacy For The Ages: Dale Sharpe, DK Photography2019-06-21T17:03:13+10:00
19 06, 2019

Know Your District! (Queensland)

2019-07-17T15:55:11+10:00

When it comes to severe weather, regardless of the type of the scenario, one of the age old questions we receive on Higgins Storm Chasing, as well as any other weather page across the globe is ‘Will this affect me at x”. Generally ‘districts’ or much broader areas are labelled rather than specific towns. This is largely due to weather being unpredictable down to the nearest town and weather systems being quite large which means their potential is spread over hundreds of kilometres. Its also due to there sometimes being so many town, that the list would be far too long for it to be beneficial. Some setups or systems are easier to predict than others, but even in those situations, districts or parts of district (i.e Coastal parts of the Northern Rivers and South East QLD Coast) are labelled. 

 

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QUEENSLAND has 15 districts according to the Bureau of Meteorology which is the most reliable source for when it comes to district mapping in regards to weather. These districts including their respected towns or cities include – obviously not all towns are named, but if you recognise a nearby town, then chances are you are included in that district:

1 – Peninsula: Weipa, Coen, Lockhart River, Musgrave, Aurukun, Thursday Island, Palmerville.
2 – Gulf Country: Mornington Island, Normanton, Kowanyama, Burketown, Karumba, Doomadgee, Myola, Croydon, Four Ways, Gregory Downs, Sweers Island, Pormpuraaw.
3 – 
Northern Goldfields & Upper Flinders: Hughenden, Richmond, Nonda, Georgetown, Charters Towers, Homestead, Einasleigh, Mount Surprise, Forsayth.

 

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4 – North Tropical Coast & Tablelands: Cairns, Innisfail, Atherton, Ravenshoe, South Johnstone, Port Douglas, Cape Tribulation, Cooktown, Daintree, Tully, Bilyana, Cardwell, Kirrama, Herberton, Wujal Wujal, Tinaroo, Gordonvale, Babinda, Mareeba, Mossman, Abergowrie, Japoonvale, Hope Vale.
5 – 
Herbert & Lower Burdekin: Townsville, Ingham, Ayr, Giru, Rollingstone, Halifax, Mingle, Dalbeg, Ravenswood, Clare, Home Hill, Alva, Nelly Bay, Magnetic Island, Greenvale, Hidden Valley, Bluewater, Deeragun, Woodstock, Lucinda.
6 – Central Coast & Whitsundays: Mackay, Sarina, Whitsunday Islands including Hamilton Island, Airlie Beach, Proserpine, Koumala, Carmila, Nebo, Finch Hatton, Eungella Ranges, Bowen, Collinsville, Eton, Marian, Hay Point, Cannonvale.
7 – Capricornia: Rockhampton, Gladstone, Emu Park, Yeppoon, Mount Morgan, Mount Larcom, St Lawrence, Biloela, Moura, Theodore, Calliope, Miriam Vale, Jambin, Byfield, Shoalwater.
8 – Central Highlands & Coalfields: Emerald, Taroom, Blackwater, Dingo, Moranbah, Clermont, Sapphire, Springsure, Rolleston, Comet, Dysart, Alpha, Sedgeford, Willows Gemfields, Middlemount, Glendon.
9 – Central West: Longreach, Ilfracombe, Blackall, Muttaburra, Barcaldine, Aramac, Tambo, Jericho, Cornfield, Winton, Morella, Tocal, Yaraka.
10 – North West: Mount Isa, Cloncurry, Julia Creek, Cannington, The Monument, Urandangie, Dajarra, Duchess, Kynuna, McKinlay, Camooweal.
11 – Channel Country: Birdsville, Boulia, Thargomindah, Jundah, Windorah, Diamantina Lakes, Stonehenge, Bedourie, Ballera, Eromanga, Quilpie.
12 – Warrego & Maranoa: St George, Charleville, Bollon, Cunnamulla, Morven, Mitchell, Roma, Augathella, Eulo, Dirranbandi, Hungerford, Injune, Surat, Durham.

 

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13 – Darling Downs & Granite Belt: Warwick, Stanthorpe, Toowoomba, Clifton, Inglewood, Dalby, Oakey, Chinchilla, Tara, Cecil Plains, Goondiwindi, Meandarra, Wandoan, Miles, Thallon.
14 – Wide Bay & Burnett: Gympie, Tin Can Bay, Hervey Bay, Maryborough, Bundaberg, Childers, Gin Gin, Crows Nest, Nanango, Kingaroy, Murgon, Durong, Mundubbera, Eidsvold, Monto, Seventeen Seventy, Proston, Gayndah, Tiaro, Fraser Island.
15 – South East Coast: Brisbane, Ipswich, Amberley, Archerfield, Caboolture, Redcliffe, Gold Coast, Beaudesert, Boonah, Esk, Sunshine Coast, Noosa, Sunshine Coast Hinterland, Gold Coast Hinterland, Rathdowney, Coolangatta, Gatton, Kilcoy, Lowood, Moreton Island, South & North Stradbroke Islands.

Often while producing more broad scale weather forecasts, we will often group several districts together and use an overriding term, such as ‘South Eastern QLD’. When we use the term ‘South Eastern QLD’, we are often referencing the South East Coast, Darling Downs, Granite Belt, Wide Bay & Burnett and sometimes the Capricornia – its roughly South of a line from Rockhampton to Emerald and East of Roma and St George. ‘Inland’ refers to areas West of the Great Dividing Range, while Southern Inland will include the Warrego & Maranoa, Darling Downs & Granite Belt. Central Inland will reference the Central West & Central Highlands and Northern Inland will be for the Northern Goldfields and parts of the North West districts. 

Outline of the South East QLD district with many town names included. Base image via Weatherzone

 

 

Know Your District! (Queensland)2019-07-17T15:55:11+10:00
19 06, 2019

Severe Thunderstorm Watch #A [TEST]

2019-08-24T17:39:04+10:00

THIS IS A TEST POST ONLY – NEW HSC PUBLIC SEVERE THUNDERSTORM WATCH ALERT PRODUCT!

 

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Severe Thunderstorm Watch for inland parts of South East QLD and North East NSW! 

Issued: 11:45am EST October 3rd, 2018 
Valid: 3pm to 7pm, October 3rd, 2018.

Current Weather Situation: A surface trough has developed between Miles, Goondiwindi & Narrabri over Southern QLD and Northern NSW. This trough has enabled cumulus clouds to develop according to satellite imagery over the Darling Downs and North East parts of NSW with increased heating and moisture still expected over the next several hours. Thunderstorms are expected to develop further West from the ‘WATCH’ area, however with increased instability over the highlighted areas, these storms should increase in strength and become severe within the ‘WATCH’ area during the afternoon and evening. Damaging winds, heavy rain and large hail are all possible. 

Severe Thunderstorm Risks:
Damaging Winds = HIGH
Large Hail = MODERATE
Heavy Rain = HIGH

Districts that may be affected include:
Darling Downs, Granite Belt, North West Slopes & Plains, Northern Tablelands.


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A severe thunderstorm watch specifically uses live weather data observations coupled with pre existing forecast data only. For more information on what a ‘Severe Thunderstorm Watch’ means please Click hereFurther severe thunderstorm watch areas are possible for locations further East as thunderstorms progress and the potential for severe thunderstorms is more confident than currently indicated. Individual severe thunderstorm WARNINGS will be issued in addition to the thunderstorm watch area once thunderstorms have reached severe criteria
Please ensure to continually check our website, email alerts, facebook page and facebook group for live updates and warnings which will include radar images and visual content. 


Detailed daily thunderstorm and rainfall forecast maps are available through our subscription service. Click here or on the image below for more information! 

 

Disclaimer: This severe thunderstorm watch is 100% issued and endorsed by “Higgins Storm Chasing”. It is in no way a reflection of other businesses, brands, government departments or otherwise. It is based solely on our opinion and is issued as a method of providing advanced public warning about the “potential” for severe weather. Our thunderstorm watch maps and text content is strictly NOT for media use without permission. [wp_ad_camp_4]

 

 

Severe Thunderstorm Watch #A [TEST]2019-08-24T17:39:04+10:00
18 06, 2019

What Is A Severe Thunderstorm ‘WATCH’?

2019-06-18T21:42:12+10:00

A new concept for Higgins Storm Chasing is the issuance of a ‘Severe Thunderstorm Watch’. This feature or concept will be greatly used during the severe weather season between October and April in particular, but is plausible any time of year that severe thunderstorms are deemed to be an increased risk. What this feature enables is further advanced warning of severe weather (specifically thunderstorms) on a specific day. 

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Firstly, its important to understand what a ‘WATCH’ is. 
Severe thunderstorm ‘WATCH’ areas, are typically areas that are showing signs of producing severe weather (thunderstorms in particular) ahead of any development occurring. This is DIFFERENT to a warning, which is issued specifically for a thunderstorm that has severe characteristics already occurring. Often, the radar will show no activity at all when a watch is issued. This is also DIFFERENT from a forecast. A forecast is an indication of what computer model data is showing potential for, whereas a ‘WATCH’ is also incorporating some live data to not just narrow down more specific areas, but also narrow down more specific threats and more specific timing for such events to occur. 

A ‘watch’ will be issued, when various characteristics are being noted on both forecast models, live data (such as radar and satellite) as well as live soundings (weather balloon soundings). This combination will lead to various areas on any given day being placed under a ‘watch’ area as their specific data is indicating severe thunderstorms are more likely than not to occur. 

Each thunderstorm watch will be a continuing number for the season. This will mean ‘Watch #111’ won’t be the 111th for the day, it will be the 111th for the season. What this will mean is no severe thunderstorm watch will be confused with another, as the same areas may receive multiple watches on multiple days during the season.

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What does a ‘WATCH’ mean?
A severe thunderstorm watch means that live data is showing that severe thunderstorms are more likely than not to occur within the specific shaded area or outlined area. While NOT every thunderstorm within this area will become severe, it merely is there for further advanced warning that between these certain times (for example 3pm and 8pm), conditions will be favourable for severe thunderstorms to develop. 

It is worth noting and also important to understand, that severe thunderstorms can occur outside of ‘WATCH’ areas. A ‘WATCH’ zone is not the bee-all and end-all of severe weather. For example, a severe thunderstorm watch may be issued for the Darling Downs, North West Slopes and Plains, Northern Tablelands and Granite Belt districts for 2pm to 7pm. However severe storms may develop over North West NSW and Southern Inland QLD earlier than that and then move into that area. In this scenario, a severe thunderstorm watch isn’t covering the Northern Rivers or South East QLD Coast – this doesn’t mean severe storms won’t reach the Coast, a secondary watch may be required at 4pm for the 6pm to 10pm timeframe as storms move closer to the Coast and conditions remain favourable for severe storms reaching the Coast.

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What threats are included in a Severe Thunderstorm Watch?
Severe storms are thunderstorms that are capable of producing damaging winds in excess of 90km/h, heavy rain which may lead to localised flash flooding and large hail (hailstones greater than 2cm). Not every severe storm is capable of producing all 3 threats. Some only produce damaging winds, some only heavy rain, some only large hail and some can produce a combination of the 3. Its important to read the severe thunderstorm watch text which will be provided as each specific watch will indicate the main risks or categorise each risk for their potential to occur – ie. Damaging winds “high chance”, heavy rain “low chance”, large hail “low chance” – this would be damaging winds are the main threat. If all 3 risks are classed as “high”, then all 3 risks may occur.

For reference,
“LOW” is less than a 25% chance, or in other words 1 in 4 severe storms
“MODERATE” is between 25 and 50% chance, or in other words roughly 1 in 3 or every second severe storm
“HIGH” is between 50 and 75% chance, or greater than 1 in every 2 storms
and, “VERY HIGH” is a greater than 75% chance of occurring. 

Of course, in rarer circumstances, destructive winds in excess of 125km/h, giant hail (hailstones in excess of 5cm in diameter) and torrential rainfall may occur – these watches will be classed as “very dangerous”. In the even rarer circumstance that conditions become favourable for tornadoes, then a tornado watch or supercell watch featuring tornadoes will be issued. 

What Is A Severe Thunderstorm ‘WATCH’?2019-06-18T21:42:12+10:00
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