Below Normal Temperatures Expected for Most

GENERAL OVERVIEW:

A highly active weather pattern is unfolding across the contiguous United States as we move through the coming days. The dominant story is a persistent and potent storm system tracking across the central and eastern portions of the country, bringing widespread thunderstorm activity, significant heavy rain and flash flooding threats, and a broad swath of precipitation from the Gulf Coast northward into the Great Lakes. A cold front sweeping eastward will serve as the primary forcing mechanism, with multiple low pressure centers cycling through the Central Plains and Upper Midwest. Meanwhile, the West remains relatively unsettled across the Pacific Northwest and portions of the Mountain West, while the Desert Southwest stays largely dry under high pressure influence. Above-normal temperatures are the dominant thermal signal across much of the nation, with the most pronounced warm anomalies concentrated in the North Central states and Great Lakes region through much of the forecast period.

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EAST:

The eastern United States is under the influence of a broad and active weather pattern through the entire forecast period. On Sunday into Monday, a large area of rain and thunderstorms is ongoing across a wide swath stretching from the Gulf Coast northward through the Tennessee Valley, Ohio Valley, and into the Great Lakes. Most critically, a significant heavy rain and flash flooding threat is explicitly highlighted across portions of the lower and middle Mississippi Valley, including areas of Missouri, Illinois, Indiana, Kentucky, Tennessee, and Arkansas. This threat is a high-priority concern and should be taken seriously by residents across these areas, as excessive rainfall rates could lead to dangerous and life-threatening flash flooding. Severe thunderstorms are also possible across a broad corridor from the lower Mississippi Valley northeastward through the Ohio Valley and into the lower Great Lakes region during this period.

By Monday evening, the thunderstorm and rain activity remains expansive across the eastern half of the country, with precipitation extending from the Gulf Coast through the Southeast, Ohio Valley, and into the Great Lakes. A heavy rain and flash flooding threat persists and shifts slightly, remaining focused on the Illinois, Indiana, Kentucky, Tennessee, and surrounding region through Monday night into Tuesday. The cold front continues to push eastward, with rain and thunderstorm coverage remaining widespread across the Southeast and Mid-Atlantic.

As the week progresses into Wednesday and Thursday, the cold front advances further east, pushing the main precipitation shield into the Northeast and Mid-Atlantic. By Wednesday evening, rain and thunderstorm activity is focused across the Great Lakes, Ohio Valley, and into New England and the Mid-Atlantic. A low pressure system tracking through the Upper Midwest and into the Great Lakes region by Thursday maintains a broad area of rain and thunderstorms across the Northeast, with the cold front draped from the Great Lakes southward through the central Appalachians. Conditions gradually dry out across the Southeast and Ohio Valley as the frontal system exits to the east.

Temperature Anomalies:
-Days 1-3: Temperatures across the East are running above normal during this period. The Great Lakes region and portions of the Upper Midwest are seeing the most pronounced warm departures, with anomalies of 6 to 12 degrees or more above normal. The Mid-Atlantic and New England are also running modestly above normal, generally 3 to 6 degrees above average. The Southeast and Tennessee Valley are near to slightly above normal.
-Days 4-6: The above-normal temperature signal strengthens and expands across the East. The Great Lakes, Ohio Valley, and Northeast are all running well above normal, with anomalies of 6 to 12 degrees or more above average, particularly across the Upper Great Lakes and into New England. The Southeast remains near to slightly above normal.
-Days 7-10: The warm anomaly signal persists across the Northeast and Great Lakes through the end of the forecast period, with departures of 6 to 12 degrees above normal continuing across portions of New England, the Mid-Atlantic, and the Great Lakes. The Southeast and Ohio Valley trend closer to normal by the end of the period.

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CENTRAL:

The Central region is at the epicenter of the most significant weather activity during the early part of the forecast period. On Sunday, a complex low pressure system is positioned over the Central Plains, with a cold front extending southward and a warm front draped across the Northern Plains. Severe thunderstorms are explicitly highlighted as possible across a broad area encompassing the lower Missouri Valley, the mid-Mississippi Valley, and portions of the South Central states including Arkansas, Missouri, Illinois, and into the Tennessee Valley. Additionally, a heavy rain and flash flooding threat is prominently depicted across this same corridor, making this a high-impact weather event for the region. Residents from the Central Plains southeastward through the lower Mississippi Valley should be on alert for the potential for dangerous flash flooding and severe weather.

A separate area of concern exists across the Northern Plains, where mixed precipitation — including snow — is indicated near a low pressure center over the Dakotas region on Sunday. This wintry precipitation threat is confined to the immediate vicinity of the low and the associated frontal boundaries in the Northern Plains.

By Monday, the heavy rain and flash flooding threat shifts slightly eastward but remains a significant concern across the Illinois, Indiana, Missouri, Kentucky, and Tennessee corridor. The cold front continues its eastward progression, with rain and thunderstorm activity widespread from the Central Plains eastward. The Northern Plains and Upper Midwest see a transition to rain as the low pressure system tracks northeastward.

Through Wednesday and Thursday, the Central region gradually dries out from west to east as the frontal system exits. By Wednesday evening, the main precipitation focus has shifted east of the Central Plains, though lingering rain and thunderstorm activity continues near the frontal boundary across the eastern portions of the region. A new low pressure system develops over the Southwest by Wednesday, but precipitation associated with this feature remains limited to that area.

Temperature Anomalies:
-Days 1-3: The Central region is broadly above normal during this period. The most significant warm anomalies are concentrated across the Northern Plains and Upper Midwest, where departures of 9 to 12 degrees or more above normal are indicated, particularly over the Dakotas and into Minnesota. The Central and Southern Plains are running more modestly above normal, generally 3 to 6 degrees above average.
-Days 4-6: Above-normal temperatures continue across the Central region, with the warm anomaly signal remaining strongest across the Upper Midwest and Northern Plains at 6 to 12 degrees above normal. The Central Plains and South Central states are running 3 to 6 degrees above average. The Rocky Mountain region begins to see a transition toward below-normal temperatures by the end of this period.
-Days 7-10: The warm anomaly signal across the Central region weakens and becomes more fragmented. The Central and Northern Plains trend toward near-normal or slightly below-normal conditions, particularly across the Dakotas, Nebraska, and Kansas, where below-normal anomalies of 3 to 6 degrees are indicated by Days 9 and 10. The South Central states remain near to slightly above normal.

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WEST:

The western United States presents a split weather pattern through the forecast period. The Pacific Northwest and portions of the northern Rockies remain active, with rain and snow ongoing across Washington, Oregon, Idaho, and Montana during the early part of the period. A low pressure system positioned near the Pacific Northwest coast on Monday brings rain to western Washington and Oregon, with snow confined to the higher elevations of the northern Rockies and Cascades. A warm front is associated with this system, and precipitation coverage is expected to be widespread across the Pacific Northwest through Monday.

By Tuesday, the cold front associated with this Pacific system sweeps southeastward across the Intermountain West, bringing rain and snow to portions of the northern Rockies and Great Basin. Snow is indicated across higher terrain of the northern Rockies and portions of the Great Basin during this period. The Desert Southwest remains largely dry under the influence of high pressure, with a separate low pressure center developing over the Southwest by Wednesday that brings limited precipitation to that area.

Through Wednesday and Thursday, the Pacific Northwest continues to see periodic rain and mountain snow as additional disturbances move onshore. The northern Rockies maintain a threat for snow at higher elevations. The remainder of the West, including California and the Desert Southwest, stays predominantly dry under high pressure dominance.

Critical fire weather conditions are explicitly highlighted across portions of the Great Basin and Desert Southwest during the early part of the forecast period, where dry and windy conditions could support rapid fire spread.

Temperature Anomalies:
-Days 1-3: The West shows a notable contrast in temperature anomalies. The Pacific Northwest, specifically western Washington and Oregon, is running 3 to 6 degrees below normal on Day 1, with the below-normal signal extending into portions of Idaho and Montana. The remainder of the West, including the Desert Southwest, California, and the Intermountain West, is running above normal, with anomalies of 3 to 9 degrees above average across portions of the Great Basin, Nevada, Utah, and Arizona.
-Days 4-6: Below-normal temperatures become more pronounced and expand across the northern Rockies and portions of the Intermountain West, with anomalies of 3 to 9 degrees below normal indicated across Montana, Wyoming, Idaho, and into Colorado and New Mexico. The Pacific Coast states and Desert Southwest remain above normal, with California seeing modest warm anomalies of 3 to 6 degrees above average.
-Days 7-10: The below-normal temperature signal in the Intermountain West and northern Rockies persists and expands further southward, with departures of 3 to 9 degrees below normal extending from Montana southward through Wyoming, Colorado, and into New Mexico by Days 9 and 10. Meanwhile, the Pacific Coast — particularly the Pacific Northwest and California — trends increasingly above normal, with anomalies of 6 to 12 degrees above average indicated along the coast by the end of the period.

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TROPICAL:

No tropical cyclone activity is anticipated in the Atlantic basin or Gulf of Mexico during the next seven days. In the Eastern Pacific, a tropical depression named Amanda is currently located well west of the Mexican coastline in the open Pacific, tracking away from land and posing no threat to the United States. Additionally, two disturbances are being monitored in the vicinity of the eastern Pacific coast of Mexico and Central America, with development possible over the coming days, though neither is currently expected to impact the continental United States.