Clashing air masses to bring flood threat from New Mexico to Michigan by midweek
A clash between two air masses will bring a narrow, but heavy swath of showers and thunderstorms extending from the Desert Southwest to the Great Lakes into midweek.
By
Brandon Buckingham, AccuWeather Meteorologist
Published Sep 29, 2019 9:11 AM EDT
The streets of Peoria, Illinois, flooded on Sept. 27, forcing many residents off the road. The flooding also took one resident's fall decorations along with it down hill.
A clash between two air masses will bring a narrow, but heavy swath of showers and thunderstorms extending from the Desert Southwest to the Great Lakes into midweek.
This flood threat will be coming on the heels of a flash flooding event that took place this past weekend in many of the same areas across the Midwest. A swath of flash flood warnings were issued Saturday night extending from eastern Kansas to southern Michigan.
In similar fashion to the event this past weekend, there is a threat for multiple rounds of thunderstorms to occur over the same area, leading to an enhanced flood threat.
Two separate sources of fuel for heavy rain will come together during this event. Hot and humid air streaming in from the Gulf of Mexico, as well as moisture from the Pacific Ocean will act as fuel for heavy thunderstorms.
The fuel required to support thunderstorm growth is just one piece of the puzzle that will come together. In the upper levels of the atmosphere, a "roller coasterlike" pattern in the jet stream will also act to aid in putting proper large-scale dynamics for thunderstorm development in place over the region.
As the hot and steamy air mass from the Gulf tracks northward into the Plains and Midwest, it will be met by a much colder air mass in place over the Rockies and northern Plains. As the two air masses collide, the warm, moist air is forced upward, which then cools and condenses, forming what will eventually become showers and thunderstorms.
This clash of air masses and heavy rain can be expected for places like Amarillo, Texas; Wichita, Kansas; Des Moines, Iowa; and Grand Rapids, Michigan.
With soil across much of the Midwest nearly saturated, flash flooding can occur quickly. Chicago has received over 200% of their average rainfall for the month of September, and many other cities in Illinois, Iowa and Wisconsin, have observed similar conditions.
Across portions of New Mexico and Texas, this round of storms should act to ease drought concerns across the area. Of course, too much rain in a small amount of time can bring along other issues in the form of flash flooding.
This heavy rain threat is coming at a critical time for area farmers in the region. Excessively heavy rainfall can cause a multitude of difficulties when it comes time to harvest. Large tractors and harvesting combines may have difficulties driving through the fields, or in some cases, may not be able to get out to harvest until conditions dry out.
Across the Great Lakes, the heavy rain is also coming at a difficult time as anglers from around the country head out to area rivers in search of salmon, steelhead and native trout. Excessive rain can act to flood area rivers and streams, rendering the river unwalkable and forcing fisherman to call it quits.
A swath of 2 to 4 inches of rain can be expected across much of the region in question through Wednesday. Some localized areas may even reach an AccuWeather Local StormMax® of 8 inches before the storms wrap up.
Conditions will begin to settle down across the Midwest heading into late week as an expansive area of high pressure is slated to settle in over the region. Much cooler air and sunnier skies are expected for many this weekend.
Farther south across West Texas, New Mexico and Kansas, unsettled weather may continue right through the end of the week and into the weekend, possibly further exacerbating flooding concerns.
Download the free AccuWeather app to receive the latest forecast and severe weather watches and warnings. Keep checking back for updates on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
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Clashing air masses to bring flood threat from New Mexico to Michigan by midweek
A clash between two air masses will bring a narrow, but heavy swath of showers and thunderstorms extending from the Desert Southwest to the Great Lakes into midweek.
By Brandon Buckingham, AccuWeather Meteorologist
Published Sep 29, 2019 9:11 AM EDT
The streets of Peoria, Illinois, flooded on Sept. 27, forcing many residents off the road. The flooding also took one resident's fall decorations along with it down hill.
A clash between two air masses will bring a narrow, but heavy swath of showers and thunderstorms extending from the Desert Southwest to the Great Lakes into midweek.
This flood threat will be coming on the heels of a flash flooding event that took place this past weekend in many of the same areas across the Midwest. A swath of flash flood warnings were issued Saturday night extending from eastern Kansas to southern Michigan.
In similar fashion to the event this past weekend, there is a threat for multiple rounds of thunderstorms to occur over the same area, leading to an enhanced flood threat.
Two separate sources of fuel for heavy rain will come together during this event. Hot and humid air streaming in from the Gulf of Mexico, as well as moisture from the Pacific Ocean will act as fuel for heavy thunderstorms.
The fuel required to support thunderstorm growth is just one piece of the puzzle that will come together. In the upper levels of the atmosphere, a "roller coasterlike" pattern in the jet stream will also act to aid in putting proper large-scale dynamics for thunderstorm development in place over the region.
As the hot and steamy air mass from the Gulf tracks northward into the Plains and Midwest, it will be met by a much colder air mass in place over the Rockies and northern Plains. As the two air masses collide, the warm, moist air is forced upward, which then cools and condenses, forming what will eventually become showers and thunderstorms.
This clash of air masses and heavy rain can be expected for places like Amarillo, Texas; Wichita, Kansas; Des Moines, Iowa; and Grand Rapids, Michigan.
With soil across much of the Midwest nearly saturated, flash flooding can occur quickly. Chicago has received over 200% of their average rainfall for the month of September, and many other cities in Illinois, Iowa and Wisconsin, have observed similar conditions.
Across portions of New Mexico and Texas, this round of storms should act to ease drought concerns across the area. Of course, too much rain in a small amount of time can bring along other issues in the form of flash flooding.
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This heavy rain threat is coming at a critical time for area farmers in the region. Excessively heavy rainfall can cause a multitude of difficulties when it comes time to harvest. Large tractors and harvesting combines may have difficulties driving through the fields, or in some cases, may not be able to get out to harvest until conditions dry out.
Across the Great Lakes, the heavy rain is also coming at a difficult time as anglers from around the country head out to area rivers in search of salmon, steelhead and native trout. Excessive rain can act to flood area rivers and streams, rendering the river unwalkable and forcing fisherman to call it quits.
A swath of 2 to 4 inches of rain can be expected across much of the region in question through Wednesday. Some localized areas may even reach an AccuWeather Local StormMax® of 8 inches before the storms wrap up.
Conditions will begin to settle down across the Midwest heading into late week as an expansive area of high pressure is slated to settle in over the region. Much cooler air and sunnier skies are expected for many this weekend.
Farther south across West Texas, New Mexico and Kansas, unsettled weather may continue right through the end of the week and into the weekend, possibly further exacerbating flooding concerns.
Download the free AccuWeather app to receive the latest forecast and severe weather watches and warnings. Keep checking back for updates on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.