The Rain 'Machine' Affecting The South On Mother's Day Weekend
The Gulf Coast region and much of the southeastern U.S. is locked into a weather pattern that will bring rainfall to the region all weekend and into the first part of the work week too. Here's a meteorological explanation of the 'rain machine' affecting the Southeast this Mother's Day weekend.
The Scenario
NOAA's Weather Prediction Center wrote, 'A dawdling storm system along the Gulf Coast will generate rounds of heavy rain and thunderstorms this weekend and into the first half of next week." The culprit is an upper an upper-level low that is meandering over the Deep South, according to WPC. Meteorologically, there is plenty of Gulf moisture and a stationary front will also provide a source of 'lift' that could trigger thunderstorms daily. WPC noted, '…. An expansive Marginal Risk (threat level 1/4) for Excessive Rainfall that stretches from the Lower Mississippi River Valley to as far east as the Southeast coast each day this weekend.' WPC has issued a Slight Risk (threat level 2/4) for parts of the Florida Panhandle, Alabama, Georgia, and South Carolina.
By Sunday, the upper low will not have moved very much at all and will still be sitting over Louisiana. That cutoff low scenario provides a 'pump' of moisture into the Southeast. For most of us that means a wet Mother's Day. Let's further explore the meteorology of what's going on.
Risk of excessive rainfall on Mother's Day.
NOAA
What is a Cutoff Low?
The 'rain machine' that I am referring to is not some wacky conspiracy theory. As soon as I typed that my 'spidey senses tingled' because sadly there are fringe factions that may miss the metaphor. That's a slight digression, let's stay on task. University of South Alabama meteorologist Jordan McLeod nailed it. He called it, 'A classic cutoff low pattern in a transition season.'
The cutoff low over Louisiana on Sunday morning.
College of Dupage/NWS/NOAA
What is a cutoff low? The National Weather Service glossary defined it as, 'A closed upper-level low which has become completely displaced (cut off) from basic westerly current, and moves independently of that current. Cutoff lows may remain nearly stationary for days, or on occasion may move westward opposite to the prevailing flow aloft (i.e., retrogression).' That's what is happening in this scenario. The low in the graphic below is going to sit in the same spot for a few days before finally moving out during the middle of the week.
Meteorologically, the circulation around a 'low' is counterclockwise in the northern hemisphere. With the low positioned over Louisiana, moisture flow into the Southeast is coming from the Gulf region. In 2009, the Atlanta area experienced major flooding, and the culprit was a cutoff low situated to the west of Georgia. Our research group published an overview of that event in 2011. A 2025 study published in the journal Nature suggested that long-lasting cutoff lows will become more frequent in the Northern Hemisphere.
Is It An Atmospheric River in the South?
While the term 'atmospheric river' is more commonly associated with the West Coast, the water vapor metrics used to define them indicate that this is an 'atmospheric river' setup. NOAA defined atmospheric rivers as, 'Relatively long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics.' Ben Noll described this weekend atmospheric river scenario in the Washington Post.
Though less common than western counterparts, atmospheric rivers in the Southeast do happen. Our research team at the University of Georgia, led by Dr. Neil Debbage now at University of Texas San Antonio, published a 2017 study documenting ARs that hit the southeastern U.S from 1979 to 2015.
If you are in the Southeast, make sure you have an umbrella as you go out for those Mother's Day lunches and dinners.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
4 hours ago
- Yahoo
How to Watch the Northern Lights for the Second Time this Week
The northern lights are predicted to be "quite pleasing to look at" due to their Kp index forecast of a five out of nine on Saturday, June 14 The colorful spectacle is expected to be visible this weekend due to the arrival of a coronal hole high-speed stream a few days prior, according to NOAA States that don't typically get the chance to spot the northern lights, like New York, might be able to catch a glimpseJust when you thought the galaxy couldn't get any more dazzling! A little over 48 hours after the beautiful Strawberry Moon lit up the night sky on June 11, the northern lights are predicted to color the cosmos with a second aurora display this week. A moderate geomagnetic storm (G2) watch has been issued by the National Oceanic and Atmospheric Administration (NOAA)'s forecast for Saturday, June 14 due to the arrival of a coronal hole (CH) high-speed stream (HSS) a few days prior. NOAA explains, "A coronal hole is a less dense area in the solar corona. They appear dark because they are cooler. Solar wind escapes from these features at higher speeds, known as High-Speed Streams. When they arrive at Earth, escalated geomagnetic activity may result." This time, the northern lights are predicted to be visible from Earth in various locations across the United States. Even a few states that don't normally have the chance to spot the auras, like New York, might be able to catch a glimpse. The upcoming auroras come shortly after the northern lights were forecast for the night of June 7. They were forecast for 15 states. Read on for how to watch the upcoming northern lights! As a result of the moderate geomagnetic storm (G2) watch in effect, NOAA predicts the northern lights to be visible from Earth on the night of Saturday, June 14 into the early morning on Sunday, June 15. The auroras are forecast to be a five on the Kp scale of zero to nine. This means, the light display can be "quite pleasing to look at" if situated in the right spot and the weather conditions align. Should the forecast increase to a six, the colors can be "quite bright and active," per NOAA. Viewers will have a chance to spot the auroras in the days leading up to June 14, however the forecast isn't as strong. A three out of nine on the Kp scale is forecast for Thursday, June 12 and a four out of nine is forecast for Friday, June 13. It's best to look for the northern lights in the hours leading up to sunset and right before sunrise. They won't be visible in daylight. The northern lights predicted for June 14 are expected to be visible from various locations across the United States, including areas that don't typically have the chance to spot them from Earth. According to NOAA, the northern lights may become visible over some northern and upper Midwest states from New York to Idaho. Keep checking the space organization's website for the most accurate viewing updates as the night gets closer. No advanced technology is required to view the northern lights. Simply, the naked eye is capable of spotting the colorful display from Earth if the weather conditions cooperate. It's also recommended to find a viewing area that's away from light pollution, like city lights, that can drown out the colors in the night. Dark areas are optimal for spectating! Did the northern lights really happen if you didn't take a picture? Several smartphones have a high-tech capability to capture the phenomenon on camera if you toggle on the "Night Mode" setting. Read the original article on People
News24
8 hours ago
- News24
Friday's weather: Morning fog with cold to cool conditions for most of SA
Most parts of the country can expect morning fog with cold to cool conditions, but light rain is forecast for Limpopo, according to the South African Weather Service (SAWS). The weather in your province Gauteng: Morning fog patches and frost in the southern areas. Expect fine and cold to cool conditions throughout the day. Pretoria: 5°C — 19°C Johannesburg: 5°C — 18°C Vereeniging: 2°C — 18°C Mpumalanga: Morning fog patches over the Highveld. Areas in the east may experience partly cloudy weather, though most regions will be fine and cold to cool. Mbombela: 8°C — 20°C Ermelo: 1°C — 16°C Emalahleni: 3°C — 16°C Standerton: -3°C — 17°C Skukuza: 5°C — 23°C Limpopo: Fog is anticipated along the northern escarpment in the morning. There is a chance of light rain in the extreme north-east, with partly cloudy and cool weather elsewhere. Polokwane: 4°C — 19°C Phalaborwa: 7°C — 23°C Tzaneen: 8°C — 20°C Musina: 9°C — 23°C Lephalale: 9°C — 21°C Mokopane: 3°C — 18°C Weather update for today and tomorrow, 12-13 June 2025: Fine and cold to cool weather conditions but partly cloudy with isolated showers and rain in the north. #saws #saweather — SA Weather Service (@SAWeatherServic) June 12, 2025 North West: The province will remain fine and cool. Klerksdorp: 2°C — 18°C Potchefstroom: 3°C — 19°C Mahikeng: 5°C — 17°C Rustenburg: 6°C — 19°C Vryburg: 1°C — 20°C Free State: A cold to cool day is expected with clear skies across the region. Bloemfontein: 1°C — 18°C Welkom: 3°C — 18°C Bethlehem: 1°C — 17°C Northern Cape: The coast will enjoy warm to hot weather. Cooler conditions will dominate elsewhere, especially in the south where it will be cold. The coast will experience moderate to fresh north-easterly winds, shifting later to a light easterly to south-easterly direction. Upington: 5°C — 23°C Kimberley: 2°C — 19°C De Aar: 2°C — 17°C Alexander Bay: 16°C — 32°C Springbok: 11°C — 21°C Calvinia: 4°C — 22°C Sutherland: -3°C — 19°C Western Cape: Fine and cool conditions for most of the province but warm in some western areas. Coastal winds will vary from light to moderate northerly to north-easterly, with fresher winds along the northern parts of the west coast. Cape Town: 11°C — 24°C Vredendal: 7°C — 28°C Riversdale: 6°C — 25°C George: 6°C — 22°C Worcester: 3°C — 25°C Beaufort West: 3°C — 21°C Oudtshoorn: 4°C — 22°C Western half of the Eastern Cape: Morning frost is expected in parts of the north, followed by fine and cool conditions. Light north-westerly winds will prevail along the coastline. Eastern half of the Eastern Cape: The day will be mostly fine and cool, with colder conditions in the northern high-lying areas. Coastal winds will remain light and variable. Gqeberha: 8°C — 23°C Makhanda: 8°C — 22°C Cradock: 4°C — 20°C Graaff-Reinet: 5°C — 22°C East London: 12°C — 22°C Port St Johns: 11°C — 22°C Mthatha: 5°C — 21°C Komani: 3°C — 19°C Qonce: 7°C — 22°C KwaZulu-Natal: Fine and cool weather is forecasted, though it will be colder in the south-west. The coast will experience light to moderate winds, shifting through the day from a north-westerly to a north-easterly direction. Durban: 13°C — 21°C Richard's Bay: 13°C — 23°C Pietermaritzburg: 5°C — 20°C Ladysmith: 1°C — 19°C
The Hill
9 hours ago
- The Hill
Geomagnetic storming could spark northern lights this weekend: What to know
(NEXSTAR) — Some in the U.S. could have another chance to see the northern lights this weekend thanks to a coronal hole and accompanying solar winds that may impact Earth. NOAA's Space Weather Prediction Center has issued a geomagnetic storm watch for Saturday because of the coronal hole, or CH. These are areas on the sun that are cooler and less dense regions of open and unipolar magnetic fields, NOAA explains. Their openness allows solar wind to escape at higher speeds, known as High Speed Streams, or HSS. A CH HSS can spark geomagnetic storms on Earth, according to NOAA, though not typically as strong as those brought on by coronal mass ejections, like we saw earlier this month. The CH HSS could still pack a punch to our atmosphere, however. While there could be some infrastructure-related impacts, experts say those in charge of those systems are equipped to mitigate influences. For those of us not responsible for power systems and navigational products, we may get to enjoy a more colorful outcome of geomagnetic storms: the northern lights. The SWPC has issued a G2-level watch starting on Saturday. At that level, which is not uncommon, the northern lights have been known to be visible in parts of the Midwest, Idaho, and New York. It's difficult to say exactly where the aurora could be visible on Saturday, however. The SWPC offers two days worth of aurora viewing forecasts — for the present day and the next — as well as a three-day forecast. As of Thursday, the Kp index, used to measure the magnitude of geomagnetic storms, is expected to strengthen later in the day on Saturday, starting between 9 a.m. and 12 p.m. UTC, or between 5 a.m. and 8 a.m. EDT. That means the morning sun will drown out the northern lights, if they're even visible at that time. However, the SWPC's forecast shows conditions could ramp up through the day, potentially reaching a Kp index of 5.67, considered G2-strength storming, at around 5 p.m. EDT. Should geomagnetic storming remain on the stronger side for the following hours, you could see the northern lights Saturday night. The aurora forecasts produced Friday and Saturday should offer a better insight into where in the U.S. the aurora could be visible. The aurora forecast produced by the University of Alaska Fairbanks Geophysical Institute, which uses data from NOAA but is often based on long-term predictions, shows Canada has a greater chance of seeing the northern lights on Saturday. The celestial show could, however, be visible to those in all or parts of Washington, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, New York, Vermont, New Hampshire, and Maine. Forecasts from the SWPC and the Institute could change before Saturday, depending on a multitude of conditions. Experts previously told Nexstar its difficult to forecast geomagnetic storming conditions until the material causing it — in this case, a CH HSS — is closer to Earth. If you live in an area where the aurora is forecast to reach, but you're unable to see the colors in the night sky, try using your phone to catch a glimpse. Since the cameras on our smartphones are more sensitive than our eyes, they can better pick up on the celestial show during weaker conditions. It's recommended to use your phone camera's night mode, if available, or another method of extending the camera's exposure. You'll also want to keep your hands as steady as possible, which may mean relying on a tripod.
