Thursday, October 1, will bring sharply different weather conditions across some of the world's largest cities.
Sydney is heading for an unusually warm spring day with temperatures around 32°C, while parts of the United States will also remain warm. Miami faces thunderstorms and Chicago is preparing for persistent rain.
Across Europe, conditions will generally be calmer. London and Berlin should enjoy sunshine, while Paris is expected to improve considerably after some overnight rain.
Here is the latest outlook for major cities across the United States, United Kingdom, Germany, France, Canada and Australia.
United States: Big differences from coast to coast
Weather conditions will vary dramatically across the United States on Thursday.
New York
New York City is expected to reach approximately 24°C, with temperatures falling to around 18°C overnight.
Conditions should remain mostly cloudy, although significant rainfall is not currently expected. Winds will generally remain light to moderate.
The relatively mild temperatures make Thursday a comfortable early October day for residents and visitors.
Los Angeles
Los Angeles will remain considerably warmer.
Temperatures are expected to approach 30°C, with overnight readings around 18°C to 19°C.
Conditions should remain largely dry, with sunshine dominating much of the day.
For travelers arriving in Southern California, summerlike clothing will still be appropriate during the afternoon.
Chicago
Chicago faces one of the wettest forecasts among the major cities covered in Thursday's outlook.
Temperatures should reach around 21°C to 22°C, but rain is expected through significant portions of the day.
Forecasts indicate a very high probability of rain, with locally heavy rainfall possible.
Anyone commuting in Chicago should allow additional travel time, particularly if heavier rain develops during the afternoon.
Miami
Miami will remain hot and humid, with temperatures around 28°C.
Thunderstorms are likely during the morning, followed by the possibility of additional scattered storms later in the day.
The probability of rain is around 80 percent, according to the latest forecast.
Residents and tourists should also be aware of changing coastal conditions and monitor local weather alerts.
United Kingdom: London gets a bright October start
London is heading into October with surprisingly pleasant conditions.
The Met Office forecasts a maximum temperature of approximately 21°C and an overnight minimum near 13°C.
After some cloud during the early hours, sunshine should dominate the capital through much of Thursday.
Rain probabilities fall below 5 percent for much of the daytime period.
For London commuters and tourists, Thursday should therefore provide one of the more comfortable weather days among the major European capitals.
Germany: Berlin stays warm and sunny
Berlin is also expected to enjoy favorable conditions.
The German capital could reach approximately 23°C, with nighttime temperatures near 14°C.
Sunshine is forecast for much of Thursday, with only a very small chance of rain.
The warm start to October means Berlin will feel more like late summer than the beginning of the colder autumn period.
Munich
Munich could become even warmer during the afternoon.
Forecast models indicate temperatures climbing to approximately 25°C at the warmest point of the day.
Conditions should remain largely dry through the afternoon, although cloud cover is expected and the chance of rain increases later in the evening.
People staying outside late should therefore keep an eye on updated local forecasts.
France: Paris improves after overnight rain
Paris could begin Thursday with showers and light rain during the early morning hours.
Conditions should then improve rapidly.
By late morning and afternoon, sunshine and dry weather are expected, with temperatures reaching approximately 19°C.
Nighttime temperatures could fall toward 14°C.
The best conditions for outdoor activities are expected from late morning through the afternoon.
Canada: Toronto stays mild
Toronto is forecast to reach approximately 23°C on Thursday.
Environment Canada expects cloudy conditions with a 30 percent chance of showers.
Temperatures will fall to around 13°C overnight, when the possibility of showers continues.
Despite the cloud cover, temperatures remain relatively mild for the beginning of October.
Vancouver
Vancouver will be noticeably cooler than Toronto.
The daytime maximum is forecast at approximately 16°C, with temperatures around 11°C overnight.
A mixture of sunshine and cloud is expected during the day before cloudier conditions arrive Thursday night.
For visitors, a light jacket will be useful, particularly during the morning and evening.
Australia: Sydney jumps to 32°C
One of Thursday's most striking forecasts comes from Sydney.
The Bureau of Meteorology expects temperatures to reach approximately 32°C across the Sydney area.
Conditions should remain sunny with virtually no chance of rain.
Winds are expected to become northerly to northeasterly during the day.
The UV Index is forecast to reach 8, classified as very high, making sun protection important for anyone spending extended periods outdoors.
Fire danger is also rated high in parts of the Sydney area.
For international visitors, the temperature difference is worth remembering. October marks spring in Australia, while Europe and North America are moving deeper into autumn.
Melbourne faces heavy rain
Melbourne will experience almost the opposite conditions.
The Bureau of Meteorology forecasts a maximum of around 21°C and a minimum of 17°C.
There is a 100 percent chance of rain, with approximately 10 to 25 millimetres possible during the day.
Thunderstorms are also possible during the afternoon and evening.
Melbourne could therefore experience one of the most disruptive weather days among the major cities in this forecast.
Tomorrow's temperatures at a glance
Among the major cities covered, Sydney will be one of the warmest at around 32°C.
Los Angeles follows at roughly 30°C, while Miami should reach around 28°C.
Berlin and Toronto are both expected near 23°C, New York around 24°C, Chicago near 21°C, London around 21°C, Melbourne around 21°C, Paris near 19°C and Vancouver approximately 16°C.
The largest weather contrast will not simply involve temperature.
Sydney should experience sunshine and very high UV levels, while Melbourne faces rain and possible thunderstorms. Chicago also faces substantial rainfall, while Miami could see repeated thunderstorms.
What travelers should watch on Thursday
Weather related travel disruption appears most plausible around Chicago, Miami and Melbourne, where rain or thunderstorms could affect road and air travel.
Passengers using airports in these cities should check their flight status before departure if severe weather develops.
Sydney travelers should instead prepare for heat and strong sunshine.
Across London, Berlin and Paris, weather conditions appear generally favorable for travel and outdoor activities once any early rain around Paris clears.
Forecasts can still change, particularly where thunderstorms are involved, so residents and travelers should check local weather warnings before leaving home.
Thursday's outlook ultimately provides a striking snapshot of the changing seasons around the world.
While London, Paris, Berlin and Toronto settle into autumn, Sydney begins October with temperatures above 30°C. Meanwhile, Melbourne, Chicago and Miami will be watching the skies for rain and thunderstorms.
