Big jet stream changes bring big-time weather changes to the lower-48 this week

The weather has been relatively quiet for a good chunk of the lower-48 recently, especially for the southern half of the country. The culprit of the quiet weather and milder temperatures has been the jet stream being located pretty far north. Along with the northern placement of the jet stream, it has also been relatively flat. This is known as a zonal flow, which keeps the weather pretty inactive, leading to milder temperatures and less of a wintry and severe threat across most of the lower-48. Join the Firsthand Weather Supporter Group!

Zonal flow jet stream example (courtesy NOAA)

This flat, or zonal flow, will begin to break down this upcoming week. The jet stream will start to get “kinky”, which will lead to a more active weather pattern. This active weather pattern means more rain and storms, more wintery precipitation, and colder temperatures for parts of the country that have been relatively quiet as of late. Join the Firsthand Weather Supporter Group!

Notice the animated graphic below shows a few different storm systems delivering a plethora of weather to the lower-48 over the coming days and most areas will get in on the action. From showers and storms across the Southern Plains, South, and Southeast (some of which could be severe Sunday-Tuesday) along with snow for much of the West, Plains, Great Lakes, Ohio Valley, and Northeast.

Simulated radar for this upcoming week (courtesy WeatherModels.com)

Areas of heavy precipitation are expected for the Pacific Northwest, central Rockies, and the eastern half of the country. The graphic below shows the precipitation totals through this upcoming week. Notice the Pacific Northwest will see 2-8 inches of precipitation. The valleys and lowlands will see this fall as rain while the mountains receive feet of snow. Even California, Arizona, Utah, Nevada, and New Mexico will get in on the rain with mountain snow. And yes, Colorado and Denver, you’re getting snow too! Farther east, good rain accumulations are expected for the South, Southeast, Carolinas, and Tennessee Valley. This is great news given the recent fires in the Southeast and Carolinas. Farther north, wintry precipitation is expected.

Precipitaiton accumulation forecast (courtesy WeatherModels.com)

Areas of heavy snow are expected for all the mountains out west. This is wonderful news for the snowpack and ski lovers. Feet of snow is expected. Even the mountains in southern California, and southern Arizona, and New Mexico will see inches of snow. The Great Lakes will get in on the action too with heavy snow. It’s possible some of the heavy snow extends into the Midwest and Plains with a developing winter storm later in the week but these details will be ironed out over the coming days.

Snow accumulation forecast for this week (courtesy WeatherModels.com)

Each system will have a reinforcing shot of colder air with a potentially very strong cold front late this upcoming week into the weekend!

See the latest winter outlooks below.

Read the NOAA Winter Outlook here.

Read the AccuWeather Winter Outlook here.

Read the Farmers’ Almanac here.

Read the Old Farmer’s Almanac here.

Parts of Hawaii are under a Blizzard Warning

You read that right. A Blizzard Warning is in effect for parts of Hawaii as a potent Pacific winter storm system slams the state. Heavy precipitation is expected to fall across all of Hawaii where Flood Watches have been issued. Higher in elevation, though, there will be enough cold air for heavy snow to fall. The heavy snow will be wind-driven by 100 mph wind gusts. Because of the snow and wind, a Blizzard Warning has been issued for the highest peaks of the Big Island. Mauna Loa and Mauna Kea peaks could see up to one foot of snow. Join the Firsthand Weather Supporter Group!

Blizzard Warning for Hawaii (courtesy: CBS Denver)

The Blizzard Warning goes into effect this evening and continues into Sunday morning. Snow is not unheard of in Hawaii. The highest peaks do usually see snow during the cold months, but 12 inches is quite a bit!

See the latest winter outlooks below.

Read the NOAA Winter Outlook here.

Read the AccuWeather Winter Outlook here.

Read the Farmers’ Almanac here.

Read the Old Farmer’s Almanac here.

Eyes on Thanksgiving week for a potentially significant storm to impact the Great Lakes and East Coast

All eyes are on next week as millions are expected to travel across the county to celebrate Thanksgiving. Weather models have been hinting at the possibility of a storm system impacting the Great Lakes and East Coast early to mid-next week. While the finer details are still to be ironed out, the larger-scale setup is starting to become clearer. We have been talking about this system in the Supporter Group. Join the Supporter Group today.

A potent upper-level system will dive south and east into the country’s eastern half to start the week of Thanksgiving. The main energy and lift associated with the upper-level system look to reside somewhere near the Great Lakes or Ohio Valley early next week. The track will be ironed out over the coming days. Despite most of the “oomph” with the system being farther north, part of it will extend farther south into the Southeast. This will help pull a cold front into eastern parts of the country along with the possibility of an area of low pressure developing somewhere along or just off the East Coast early to mid next week.

An animated depiction of upper-level weather pattern early to mid next week

The cold front is a certainty but the low pressure is highly questionable and depends on the evolution and track of the aforementioned upper-level system. Regardless, the upper-level system and associated cold front will bring a large area of showers and storms into the eastern half of the country. This includes parts of the Ohio Valley, Tennessee Valley, Great Lakes, Southeast, Mid-Atlantic, and Northeast. While an isolated severe storm cannot be ruled out, a strong risk for severe storms does not look probable at this point. Join the Firsthand Weather Supporter Group today.

Do notice there will be some wintry precipitation for some areas. The exact areas and amounts are highly questionable at this time, but the most likely areas to see snow are the Great Lakes and Northeast from early to mid next week. It is possible the Ohio Valley and Mid-Atlantic get in on the wintry weather too but this will be ironed out over the coming days. If this system digs a little farther south, and/or if we do get some type of low pressure to develop, it’s possible the cooling associated with the farther south track of the upper-level system or the dynamic cooling with the intensification of a surface low pressure could bring snow farther south so this will be monitored over the coming days as the details become clearer.

An animated simulated radar from early to mid next week

As the system moves east, chilly air will wrap into eastern parts of the country. This colder air will drop temperatures well below average for a good chunk of the week for areas east of the Mississippi River. With this colder air, lake effect snow showers are expected for the eastern and southern shores of the Great Lakes for a good chunk of Thanksgiving week.

Animated temperature departure from average next week

And looking beyond mid-week next week, guidance is suggesting another storm system could develop, taking aim on parts of the Rockies and Southern Plains late next week into the weekend, then possibly moving into the South and Southeast or Tennessee Valley/Ohio Valley late Thanksgiving weekend. There are a lot of questions about the evolution of this possible system but it could cause a mess of severe weather and wintry weather.

An animated depiction of upper-level weather pattern late next week

Regardless of the finer details, Thanksgiving week and weekend look hyper-active, which will likely disrupt travel most of Thanksgiving week through the weekend. Keep checking back for updates!

See the latest winter outlooks below.

Read the NOAA Winter Outlook here.

Read the AccuWeather Winter Outlook here.

Read the Farmers’ Almanac here.

Read the Old Farmer’s Almanac here.

Coastal low to impact parts of the Southeast and Carolinas

A non-tropical area of low pressure is developing in the Gulf of Mexico. This low will race east tonight and will move across Florida Friday. The area of low pressure will bring wind and rain to Florida with a low-end risk for tornadoes. By the weekend, the low will move off the Southeast Coast, bringing areas of heavy rain and gusty winds to southern and coastal Georgia, and coastal South Carolina and North Carolina this weekend. Join the Firsthand Weather Supporter Group today!

2-5 inches of rain is expected for Florida with parts of Georgia and the Carolinas receiving 1-3 inches of rain, leading to areas of flash flooding. This could change depending on the intensity and track of the low.

Gusty winds are also expected for these areas. Winds will gust up to 35 or 40 mph near the coast. Join the Firsthand Weather Supporter Group today!

Once the low pressure moves off the Southeast Coast this weekend, it’ll tap into some energy with the warm Gulf Stream, allowing it to intensify and possibly acquire some tropical characteristics. This window is small but will be monitored. Join the Firsthand Weather Supporter Group today!

There are still some questions about the intensity and track of this low. If the low tracks closer to the coast of the Carolinas, impacts will be realized farther inland for the Southeast. If the low is farther out-to-sea, then only Florida and coastal areas of the Southeast will see impacts. Join the Firsthand Weather Supporter Group today!

Tornadoes can a do occur in November, the South is particularly favored

As we begin focusing on the first frost and freeze of the season, and even the first flakes for some areas, it is important to remember that severe weather can and does still occur in November–despite average temperatures quickly decreasing throughout the month. Fall and winter storm systems in a hyper-active jet stream that plunges south provide cold, Canadian air masses clashing with warm, Gulf air masses. This leads to big-time thunderstorms, producing tornadoes from the Southern Plains into the South and Southeast. The tornado threat does extend farther north, however, into the Ohio Valley, Mid-Atlantic, and Great Lakes. Even the western states see a few tornadoes as potent storms roll in off the Pacific. Join the Firsthand Weather Supporter Group today.

November tornadoes, courtesy of the Weather Channel and James Wilson

It is important to keep a close eye on the forecast for severe thunderstorms that may enter your forecast. Have a few reliable resources to receive warnings from and have a plan in place in case a warning is issued for your area.

Severe storms and tornadoes Wednesday for the Gulf Coast States

A severe risk will develop Wednesday afternoon and evening across the Gulf Coast States as a potent cold front races east. Ahead of the cold front, strong to severe storms will develop during the afternoon and evening hours from eastern Texas, Louisiana, southern Mississippi, southern Alabama, and the Florida Panhandle. The main concern is damaging wind gusts but a few tornadoes are possible too. The highest severe threat is east of I-45 and south of I-20. Find out more details on Wednesday’s severe threat and Thursday’s severe threat as it moves east into Georgia and the Carolinas.

Wednesday’s severe risk

Make sure you keep up-to-date with tomorrow’s forecast if you live in or near an area that is expecting severe weather. Have a plan in place in case a warning is issued for your area.

Nor’easter to slam parts of New England

A developing storm system will wallop parts of New England beginning tonight, continuing through Wednesday. This storm system will really start to ramp up off the coast of New England Tuesday and Wednesday. The strengthening of the system will create some big impacts for coastal and even inland areas across the region.

Storm system off the Northeast Coast

Some of the impacts expected are coastal storm surge and large waves–creating minor beach erosion, heavy rainfall–leading to areas of flooding, and strong winds–that could down trees and create power outages.

One of the largest concerns is the rain that is expected tonight through Wednesday. A widespread 2-5 inches is in the forecast with isolater higher amounts in excess of 7 inches. This will lead to areas of flooding.

Rainfall forecast through Wednesday night

As the low pressure starts to deepen, it will produce strong wind gusts across Long Island and southern and coastal New England Tuesday-Wednesday. Wind gusts up to 60 mph are possible. This will down trees and cause some power outages.

Max wind gust forecast through Wednesday night

Large waves will also smack coastal areas. This paired with a higher storm surge due to the northeast winds piling water onshore will cause coastal eroison.

Max wave height forecast through Wednesday night

A prolonged period of severe weather is on the way

An active severe weather period is expected over the next 5 days. Each day from Saturday (October 23) through Wednesday (October 27) will have a chance for severe storms. All modes of severe weather are expected. This includes tornadoes, damaging winds, and large hail. It appears Sunday, Monday, Tuesday, and Wednesday are days that could feature higher severe weather chances with a higher probability of tornadoes.

See the images below for the severe weather chances over the next several days. Light green (general thunderstorms), dark green (marginal severe risk–level 1 of 5), yellow (slight risk–level 2 of 5), and orange (enhanced risk–level 3 of 5). It is possible upgrades are required over the coming days.

Saturday severe risk
Sunday severe risk
Monday severe risk
Tuesday severe risk
Wednesday severe risk

NOAA releases its 2021-2022 Winter Outlook

NOAA released its 2021-2022 Winter Outlook today. The forecast aligns with what climatologically happens during La Nina years. Above-average temperatures are forecast for much of the country with the highest chance for above-average temperatures across the Gulf States and Carolinas. Below-average temperatures are forecast across the Pacific & Inland Northwest into the Northern Rockies. Alaska is also forecast to experience below-average temperatures. Join the Firsthand Weather Supporter Group today!

Precipitation is forecast to be below average across the Southwest, parts of the Southern Plains, and along the Gulf Coast into the Carolinas. Farther north, above-average precipitation is forecast from the Tennessee Valley into the Ohio Valley and Great Lakes. The Pacific & Inland Northwest into the Northern Rockies can expect above-average precipitation. Join the Firsthand Weather Supporter Group today!

It should be noted: this is NOAA’s Winter Outlook. This is not Firsthand Weather’s Winter Outlook. FHW’s official outlook drops very soon so stay tuned! Join the Firsthand Weather Supporter Group today!

“Superbomb” storm in northeast Pacific

An interesting weather event is forecast to evolve in the northeastern Pacific over the next 24-48 hours. The remnants of Tropical Storm Namtheun are in the process of converting into an extratropical storm system in the northern Pacific. This process will continue on Wednesday and Thursday and the system will rapidly deepen and intensify.

The system will intensify so much that the central pressure is forecast to drop to 950 mb or lower. This is a greater than 48 mb drop in barometric pressure in a short period of time. Because of such a quick drop in pressure during the intensifcation process, this system will become what is known as a superbomb cyclone late Wednesday. This occurs when a storm system observes a drop in pressure of at least 48 mb within a 24 hour period.

European 850 hPa Wind Speeds in knots (WeatherModels.com)
European 500hPa Geopotential Height (WeatherModels.com)

This storm is forecast to bring impacts to parts of British Columbia and Alaska late this week.