Remaining Warm

GENERAL OVERVIEW: AN ACTIVE WEATHER PATTERN UNFOLDS ACROSS THE CONTIGUOUS UNITED STATES OVER THE COMING DAYS. A SIGNIFICANT SEVERE THUNDERSTORM THREAT IS UNDERWAY ACROSS THE UPPER MIDWEST AND GREAT LAKES REGION TODAY, WITH HEAVY RAIN AND FLASH FLOODING ALSO POSSIBLE IN THAT SAME AREA. THE SEVERE THREAT SHIFTS EASTWARD TOWARD THE MID-ATLANTIC AND NORTHEAST THROUGH FRIDAY. A BROAD COLD FRONT SWEEPS ACROSS THE CENTRAL AND EASTERN PORTIONS OF THE COUNTRY THROUGH THE WEEKEND, BRINGING WIDESPREAD RAIN AND THUNDERSTORMS FROM THE PLAINS TO THE EAST COAST. THE WEST REMAINS RELATIVELY QUIET WITH ONLY ISOLATED PRECIPITATION ACTIVITY, WHILE TEMPERATURES ACROSS MUCH OF THE EAST AND NORTHEAST RUN WELL ABOVE NORMAL EARLY IN THE PERIOD BEFORE A NOTABLE COOLDOWN SPREADS INTO THE CENTRAL UNITED STATES BY THE MIDDLE OF NEXT WEEK.

EAST:

Today, a low pressure system centered over the upper Midwest is driving a significant weather threat across the region. Severe thunderstorms are possible across a broad area encompassing Iowa, Wisconsin, Illinois, Indiana, Michigan, and extending into Ohio, West Virginia, Maryland, Delaware, New Jersey, and portions of the Mid-Atlantic. Within this severe threat area, heavy rain and flash flooding are also possible, particularly across Iowa, Wisconsin, and the surrounding upper Midwest. Rain and thunderstorms are widespread across the Great Lakes, Ohio Valley, and into the Northeast and Mid-Atlantic. By Friday evening, a cold front pushes eastward, and a severe thunderstorm threat shifts to the coastal Mid-Atlantic and Northeast, including New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, and Maine, as rain and thunderstorms continue across much of the eastern seaboard. Through the weekend, the cold front continues to push south and east. By Saturday evening, thunderstorms remain widespread across the Southeast, Gulf Coast, and into the Mid-Atlantic, with rain extending into the Northeast. A high pressure system builds behind the front across the Ohio Valley and Mid-Atlantic by Saturday. By Sunday evening, the cold front pushes to the Southeast and coastal areas, with rain continuing across the Northeast and a warm front lifting into New England. Rain and thunderstorms persist across the Southeast and Gulf Coast states through Sunday. By Monday, a broad area of rain and thunderstorms continues across the Southeast, Gulf Coast, and into the Mid-Atlantic and Northeast as the frontal boundary lingers near the coast.

Temperature Anomalies:
-Days 1-3: Temperatures across the Northeast, Great Lakes, Ohio Valley, and Mid-Atlantic are running well above normal, with anomalies of 6 to more than 12 degrees above normal, particularly across the Great Lakes, New England, and the Mid-Atlantic. The Southeast and Tennessee Valley are running slightly above normal. By Day 3, above-normal temperatures persist across the Northeast and Mid-Atlantic, though anomalies moderate somewhat compared to Days 1-2.
-Days 4-6: Above-normal temperatures persist across portions of the Northeast and Mid-Atlantic on Day 4, though anomalies gradually diminish. By Days 5-6, temperatures trend closer to or slightly below normal across much of the East, with only isolated above-normal anomalies remaining along the immediate Mid-Atlantic coast.
-Days 7-10: Temperatures across the East trend toward near-normal conditions through the Days 7-10 period, with most areas showing little departure from average.

CENTRAL:

Today, rain and thunderstorms are widespread across the central Plains, Midwest, and into the western Great Lakes, associated with an active low pressure system tracking across the region. A severe thunderstorm threat is ongoing across Iowa, Wisconsin, Illinois, Indiana, and Missouri, with heavy rain and flash flooding also possible across portions of Iowa and Wisconsin. By Friday evening, a cold front extends from the upper Midwest southwestward into the southern Plains, with thunderstorms continuing across the central Plains and Midwest. Rain and thunderstorms spread across the southern Plains and western Gulf Coast. By Saturday evening, the cold front sweeps southward through the central and southern Plains, with widespread rain and thunderstorms from the Dakotas and Nebraska southward through Kansas, Oklahoma, and Texas. Rain also continues across portions of the northern Plains and upper Midwest. By Sunday evening, the cold front pushes into the southern Plains and western Gulf Coast, with rain and thunderstorms continuing across the central and southern Plains. A high pressure system settles over the central Plains. By Monday, rain and thunderstorms continue across the southern Plains and western Gulf Coast, while the central Plains and Midwest see lingering precipitation.

Temperature Anomalies:
-Days 1-3: Temperatures across the central Plains and Midwest are running slightly to moderately above normal during Days 1-2. By Day 3, a cold anomaly develops across northern Montana and into the Dakotas, with temperatures running slightly below normal in that area, while the central and southern Plains remain near to slightly above normal.
-Days 4-6: A notable cold anomaly develops and expands across the northern and central Plains by Days 4-5, with temperatures running 6 to more than 12 degrees below normal across portions of Montana, Wyoming, the Dakotas, Nebraska, Kansas, and Colorado. This cold signal intensifies and spreads eastward into the Midwest by Day 6, with below-normal temperatures extending into Iowa, Missouri, and Illinois.
-Days 7-10: The below-normal temperature signal across the central Plains and Midwest gradually moderates through Days 7-10. By Day 9, temperatures across the central Plains trend back toward near normal, and by Day 10, a modest above-normal signal develops across portions of Nebraska, Iowa, and Missouri.

WEST:

The West remains relatively quiet through much of the forecast period. Today, a series of low pressure systems are present across the Southwest and Great Basin, with isolated rain and thunderstorm activity noted across portions of the Pacific Northwest, northern Rockies, and the Southwest. By Friday evening, a high pressure system is centered over the northern Rockies, with isolated precipitation continuing across portions of the northern Rockies and the Southwest. Rain activity is noted across portions of the Pacific Northwest and northern Idaho. By Saturday evening, a low pressure system is positioned over the Desert Southwest, with isolated rain and thunderstorm activity continuing across portions of the Southwest and southern Rockies. By Sunday evening, a low pressure system remains over the Desert Southwest, with isolated precipitation continuing across the Southwest and portions of the Rockies. By Monday, the West remains relatively quiet, with only isolated precipitation across the northern Rockies and Southwest.

Temperature Anomalies:
-Days 1-3: Temperatures across the Pacific Northwest, California, and the Desert Southwest are running above normal during Days 1-3, with anomalies of 6 to more than 12 degrees above normal across portions of California and Arizona. In contrast, temperatures across Montana, Wyoming, and portions of Idaho and Colorado are running below normal, with anomalies of 6 to more than 12 degrees below normal, particularly across Montana and Wyoming on Days 1-2. By Day 3, the below-normal signal contracts to mainly northern Montana and the Dakotas border region.
-Days 4-6: Above-normal temperatures persist and intensify across the Pacific Coast states, particularly the Pacific Northwest and California, with anomalies reaching well above normal by Days 5-6. Meanwhile, a cold anomaly expands across the northern and central Rockies and into the Great Basin on Day 4 before moderating somewhat. By Day 6, the Pacific Northwest and California continue to see well-above-normal temperatures.
-Days 7-10: Above-normal temperatures persist across the Pacific Coast and Intermountain West through Days 7-9, with the warmest anomalies centered over the Pacific Northwest, California, Nevada, and Utah. By Day 10, the above-normal signal across the West diminishes considerably, with most areas trending toward near-normal conditions.

TROPICAL:

In the Atlantic basin, a disturbance is being monitored in the southwestern Gulf of Mexico, near the Yucatan Peninsula region. The development potential for this system over the next seven days is assessed at less than 40 percent. No additional tropical development is expected elsewhere in the Atlantic basin at this time.

In the eastern Pacific, Hurricane Cristina is located near the Pacific coast of Central America. Cristina is currently at Category 3 intensity. Interests along the Pacific coast of Central America and southern Mexico should monitor the progress of this storm closely.