Latest news with #weatherforecasts
CNN
a day ago
- Climate
- CNN
There's a ‘ghost hurricane' in the forecast. It could help predict a real one
Hurricanes Storms Social mediaFacebookTweetLink Follow A scary-looking weather forecast showing a hurricane hitting the Gulf Coast in the second half of June swirled around social media this week—but don't panic. It's the season's first 'ghost hurricane.' Similar hype plays out every hurricane season, especially at the beginning: A cherry-picked, worst-case-scenario model run goes viral, but more often than not, will never come to fruition. Unofficially dubbed 'ghost storms' or 'ghost hurricanes,' these tropical systems regularly appear in weather models — computer simulations that help meteorologists forecast future conditions — but never seem to manifest in real life. The model responsible this week was the Global Forecast System, also known as the GFS or American model, run by the National Oceanic and Atmospheric Administration. It's one of many used by forecasters around the world. All models have known biases or 'quirks' where they tend to overpredict or underpredict certain things. The GFS is known to overpredict tropical storms and hurricanes in longer-term forecasts that look more than a week into the future, which leads to these false alarms. The GFS isn't alone in this — all models struggle to accurately predict tropical activity that far in advance — but it is notorious for doing so. For example, the GFS could spit out a prediction for a US hurricane landfall about 10 days from now, only to have that chance completely disappear as the forecast date draws closer. This can occur at any time of the year, but is most frequent during hurricane season — June through November. It's exactly what's been happening over the past week as forecasters keep an eye out for the first storm of the 2025 Atlantic hurricane season. No weather forecast model is designed in the exact same way as another, and that's why each can generate different results with similar data. The reason the GFS has more false alarms when looking more than a week out than similar models – like Europe's ECMWF, Canada's CMC or the United Kingdom's UKM – is because that's exactly what it's programmed to do, according to Alicia Bentley, the global verification project lead of NOAA's Environmental Modeling Center. The GFS was built with a 'weak parameterized cumulus convection scheme,' according to Bentley. In plain language, that means when the GFS thinks there could be thunderstorms developing in an area where tropical systems are possible – over the oceans – it's more likely to jump to the conclusion that something tropical will develop than to ignore it. Other models aren't built to be quite as sensitive to this phenomenon, and so they don't show a tropical system until they're more confident the right conditions are in place, which usually happens when the forecast gets closer in time. The western Caribbean Sea is one of the GFS' favorite places to predict a ghost storm. That's because of the Central American gyre: a large, disorganized area of showers and thunderstorms that rotates over the region and its surrounding water. The combination of abundant moisture and spin in the atmosphere makes it a prime breeding ground for storms, especially early in and during the peak of hurricane season. Given the model's sensitivity, it's quick to pounce on these possible storms. But this sensitivity has an advantage: By highlighting almost anything that could become tropical, the GFS misses very few actual storms. Its tendency to cry wolf isn't ideal, but the GFS team found it was worth giving the model a higher chance at catching every storm and better predicting each one's intensity than to prioritize fewer false alarms, Bentley explained. 'It was critical to improve the probability of detection of tropical cyclone formation and tropical cyclone intensity forecasts… and we did achieve that,' Bentley said. During the 2024 hurricane season, the GFS had the least error when forecasting the intensity of tropical cyclones – tropical depressions, tropical storms and hurricanes – of any other global forecast models in its class: the ECMWF, the CMC and the UKM. However, the ECMWF and UKM outperformed the GFS in tropical track forecasts out more than five days in the future. Despite how often the GFS conjures ghost systems in its longer term forecasts, it can't be discounted. 'The crucial role of the forecaster is to understand a model's known biases and use that knowledge to their advantage to produce a better forecast,' Bentley said. Knowing the GFS latches onto anything that could even vaguely become tropical well in advance helps forecasters keep an eye on areas where conditions may ultimately come together to create the next hurricane. The more reliable solution for predicting tropical behavior more than a few days in advance is to take advantage of ensemble forecasting, according to Bentley. 'A deterministic model like the GFS produces one forecast at a time; it gives one answer,' Bentley explained. 'An ensemble forecast can show you a variety of possible outcomes, as well as which forecast looks like a possible outlier.' Unlike social media clickbait, no well thought out forecast is made from a single model run. Forecasters use everything at their disposal – deterministic and ensemble models, observations, climatology and more – to predict weather as accurately as possible to give people the time and information they need to stay safe. The National Hurricane Center, for example, typically uses a blend of different types of models to make their forecasts. That strategy, combined with extensive expertise, led to their most accurate track forecasts on record for the Atlantic last season.
Yahoo
5 days ago
- Climate
- Yahoo
Austin weather: Bracing for summer heat, evening storm risk
The Brief Central Texas marks the start of meteorological summer Sunday with hot, humid conditions and high temperatures expected to reach the mid-90s. Isolated strong to severe thunderstorms are possible this evening, mainly north and east of Austin after 4-5 p.m., bringing risks of hail and high winds. The upcoming week will see continued heat with more scattered rain chances mid-week, and a potentially wetter pattern in 8-14 days. AUSTIN - Central Texas is ushering in meteorological summer on Sunday with mostly sunny skies, hot and humid conditions, and the potential for isolated strong to severe thunderstorms developing in the evening, particularly for areas north and east of Austin. After a week that included some below-average temperatures and significant rainfall, Sunday marks a shift to more pronounced summer-like heat. Morning temperatures started in the low 70s across the region. With a southerly wind flow drawing in warm, moist air, highs on Sunday are expected to climb into the mid-90s. Residents are advised to stay hydrated due to the heat and humidity. While much of Sunday is forecast to be dry, isolated strong to severe thunderstorms could develop after 4 or 5 p.m., with the main window for activity likely between 5 p.m. and 10 p.m. The greatest chance for these storms is north and east of the immediate Austin area. Potential threats from any severe storms include large hail, gusty straight-line winds, and a low, though not zero, chance of an isolated tornado, forecasters said. Some weather models indicate the Austin area could remain largely dry. Looking ahead, rain chances are expected to diminish on Monday. Scattered afternoon showers and thunderstorms, typical of convective summer patterns, are possible Tuesday through Thursday. The 8 to 14-day outlook suggests a trend towards wetter-than-average conditions, which could provide relief to areas experiencing drought. Temperatures throughout the upcoming week are forecast to be slightly above the seasonal average, which is typically a high of 91 degrees and a low of 71 degrees for this time of year. Highs are generally expected in the mid to upper 90s, with lows in the 70s. The Source Information in this article is from the FOX 7 Austin weather team.
The Independent
7 days ago
- Climate
- The Independent
UK weather: Will there be a ‘mini heatwave' this weekend?
As the UK basks in the sunniest spring on record, the final weekend could see temperatures reach as high as 27C. A balmy end to spring comes as provisional figures from the Met Office show 630 hours of sunshine were clocked up across the country between March 1 and May 27. However, forecasters have warned of some changeable weather as we enter the first week of summer, with the possibility of wind and rain. Looking ahead to Saturday, Met Office meteorologist Alex Burkill said 'highs of around 24C, 25C, maybe 26C or 27C' were expected towards the South East, and 'even further north, a greater chance of getting into the low 20s'. 'But we do need to factor in the brisk winds and the wetter weather that will be pushing through at times as well.' Showery rain is expected on Sunday for parts of Scotland, Northern Ireland, northern and western England and Wales. There is a better chance of dry weather in the southern and eastern parts, with some areas staying completely dry. Mr Burkill said there would be a 'bit less sunshine on offer perhaps for some of us on Sunday, and some fresher air pushing its way in, so temperatures in many places will be several degrees lower. 'Still feeling warm enough if you get any of that decent sunshine and shelter from the breeze. Some places will still get into the low 20s. 'Now there's more changeable weather to come as we go through next week.' Monday, in the first full week of meteorological summer, is likely to be the driest day of the week. Low pressure in the middle of the week will likely result in cloud and showers, according to Met Office meteorologist Alex Deakin. 'Looking pretty unsettled through the middle of next week,' he said, adding that winds coming in from the Atlantic are likely to bring moisture and showers, particularly in western areas. There may be a 'hint of a change' towards the end of next week, with wetter conditions becoming more confined to northern parts. 'But overall, next week looking pretty changeable to say the least. The winds continuing to dominate from the west or the south west, which will keep things reasonably mild, but also keeping things fairly wet, especially so in western areas. 'Complete contrast to the largely easterly conditions we've had for much of spring. 'And that hint, which is all it is at this stage, of something a bit drier in the south to end the week,' he said.
CBS News
26-05-2025
- Climate
- CBS News
Sunny Memorial Day in Philadelphia, tracking mid-week rain. See the full weather forecast.
The weather Sunday was better than Saturday in the Philadelphia area, with a bit more sunshine and highs in the 60s to near 70 in many spots, including the shore. Despite the increase in temperatures, we were almost 20 degrees cooler than this time last year when we hit a steamy 88! Next up: Memorial Day. If you're thinking about taking a dip in the ocean, brace yourself — the water is cold, sitting in the low 50s. That persistent northwest wind we've had all week has pushed the warmer surface water away from the coast, causing an upwelling of chilly water. We'll need a shift to a south or southeast wind to bring the warmer stuff back in. CBS News Philadelphia That stubborn upper-level low that kept us soggy all week is finally moving out of New England, so our weather will keep improving right through Memorial Day evening. As we take time to remember those who gave everything for our country, we should be looking at nice skies and near-average temperatures. CBS News Philadelphia Clouds increase late Monday as the next storm system brushes by to our south, bringing a few showers to Delaware and parts of South Jersey. Tuesday stays warm with highs in the upper 70s, but skies turn mostly cloudy. Then get ready for a stretch of wet weather — rain moves in Wednesday and lingers through the end of the week. Temps drop to the mid-60s Wednesday but rebound into the upper 70s by Friday. Friday could give us a break from any major rain, before showers return for the first half of the upcoming weekend. 7-day forecast CBS News Philadelphia Monday: High of 75, low of 52. Mostly sunny. Tuesday: High of 77, low of 53. Mostly cloudy. Wednesday: High of 62, low of 57. Scattered showers. Thursday: High of 75, low of 59. Scattered showers. Friday: High of 82, low of 62. Partly cloudy. Saturday: High of 81, low of 64. A shower or two. Sunday: High of 79, low of 60. Scattered showers. NEXT Weather Radars Hourly Forecast Get the latest weather info on the CBS News Philadelphia app
ABC News
23-05-2025
- Climate
- ABC News
Severe weather events predicted across Australia as flooding along NSW coast recedes
Just as flood levels start to recede along the New South Wales coast, the atmosphere will serve up further severe weather events across Australia during the coming days — from damaging winds and snow in the south, to widespread rain across the north. The blast of wintry weather for south-east states will arrive with the passage of a vigorous cold front early next week and is likely to bring the heaviest rain in at least five months to drought ravaged southern South Australia and south-west Victoria, along with a healthy dump of alpine snow. In the meantime, a major rain event will drench the country's north and interior, but thankfully no significant falls from either system will reach the swamped NSW coast. While mostly dry weather prevails in the flood zones, river levels will remain elevated for several days after the wettest May on record in parts of the Hunter and Mid North Coast. Most agricultural regions of South Australia, and a pocket of north-west Victoria has received less than 25 millimetres of rain so far in 2025. Adelaide has been slightly wetter with 31mm, however that still makes it comfortably the city's driest start to a year on record with data for comparison back to 1839. While over 1600mm of rain has drenched the NSW Mid North Coast in 2025, less than 25mm has fallen in much of SA. But finally, some rain is on the way, thanks to a powerful cold front currently surging north from the Southern Ocean. Before this system arrives, showers will brush the SA coastline today due to a weaker first front, while the low responsible for record NSW flooding will bring rain to Tasmania. The second front, easily the strongest so far this year, will then sweep across the Great Australia Bight on Sunday, and by Monday will spread showers over most of south-east Australia. While the upcoming system will barely put a dent in the substantial rain deficits which have accumulated during the past 16 months, it should help to produce around 20 to 30mm from Saturday to Tuesday from lower Eyre Peninsula, through Kangaroo Island and Fleurieu Peninsula, to south-east SA and the western Victorian coastline. Further inland rainfall intensity will drop off and less than 5mm is likely over the Wimmera, Mallee, Flinders, Riverlands and Murraylands. To the east, around 10 to 20mm should fall on the NSW central and southern ranges, along with the ranges of eastern Victoria, although the higher alpine areas should see closer to 30 or 40mm. The front will also drop temperatures by around 5 degrees Celsius in 24 hours as a mild northerly airstream is replaced by polar air from deep in the Southern Ocean. The arrival of the front will be welcomed by ski resorts — its passage overhead later Monday will cause rain to transition into a solid snowfall, and modelling shows anywhere from about 15 to 25 centimetres should accumulate on the higher slopes by Tuesday afternoon. However, resorts will be hoping for another snowfall or two during the next fortnight as a solitary dump in May normally melts before the traditional King's Birthday long weekend opening. The strength of the front will also whip up wild winds and warnings are likely in multiple states for damaging gusts. Northerly winds will strengthen tomorrow ahead of the system ahead of the first burst of gales on the SA coast in the evening. Maximum gusts should near 100 kilometres per hour, strong enough to bring down trees and lead to minor property damage and power outages. Damaging gusts will continue across much of SA on Monday and also spread across Victoria and southern NSW as the front moves rapidly east. The strongest winds will then shift to eastern NSW on Tuesday, and again gusts near 100 kph are likely in multiple districts. It might be the dry season, but an unseasonable soaking is ahead for northern Australia from the first Northwest Cloudband of 2025. The first streaks of cloud are already forming over the Kimberley thanks to a trough off the coast, and a bend in the jet stream during the coming days will enhance the band and spread it deep into the interior. The bulk of the rain will arrive across the Kimberley on Monday and Tuesday, heaviest in the west where up to 200mm is possible, around 10 times the May average and enough to trigger a Flood Watch for several rivers. The rain should also soak the central interior through Tuesday and Wednesday, including possibly in excess of 50mm around Alice Springs, around three times their May average. Even northern parts of the Top End should see dry season rain and Darwin has showers on the forecast from Monday to Thursday. As the band continues to shift east, rain should then spread through Queensland later in the week — although this far ahead it's difficult to forecast exactly where and how much rain will reach the eastern states. Below is one model's current weekly rain forecast showing the extent of the rain covering most of central and northern Australia.
