Above Normal

GENERAL OVERVIEW: AN ACTIVE WEATHER PATTERN WILL PERSIST ACROSS MUCH OF THE CONTIGUOUS UNITED STATES THROUGH THE FORECAST PERIOD. A SERIES OF LOW PRESSURE SYSTEMS AND ASSOCIATED FRONTAL BOUNDARIES WILL DRIVE WIDESPREAD RAIN AND THUNDERSTORM ACTIVITY FROM THE CENTRAL PLAINS THROUGH THE GREAT LAKES AND OHIO VALLEY DURING THE FIRST SEVERAL DAYS. HEAVY RAIN AND FLASH FLOODING THREATS WILL BE PARTICULARLY NOTABLE ACROSS PORTIONS OF THE TENNESSEE AND OHIO VALLEYS ON DAY 1, SHIFTING TOWARD THE UPPER MIDWEST AND CENTRAL PLAINS BY DAYS 2 AND 3. SEVERE THUNDERSTORM POTENTIAL WILL ALSO BE ELEVATED ACROSS THE CENTRAL PLAINS AND UPPER MIDWEST DURING THIS PERIOD. CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS PORTIONS OF THE INTERIOR WEST EARLY IN THE PERIOD. TEMPERATURES WILL TREND ABOVE NORMAL ACROSS THE GREAT LAKES, NORTHEAST, AND OHIO VALLEY THROUGH MUCH OF THE PERIOD, WHILE BELOW-NORMAL TEMPERATURES WILL GRADUALLY EXPAND ACROSS THE NORTHERN AND CENTRAL PLAINS AND ROCKIES LATER IN THE FORECAST PERIOD.

EAST:

An active and unsettled weather pattern will dominate the eastern United States through the first several days of the forecast period. On Day 1, rain and thunderstorms are widespread across the Ohio Valley, Tennessee Valley, Great Lakes region, and into the Mid-Atlantic and Southeast. A significant threat for heavy rain and flash flooding exists today across a broad corridor encompassing Wisconsin, Indiana, Illinois, Kentucky, Tennessee, and Alabama, where rainfall amounts could lead to dangerous flooding conditions. This heavy rain and flash flooding threat continues into Day 2, with the focus shifting to Kentucky and Tennessee. By Day 3, rain and thunderstorm activity remains widespread across the Great Lakes, Ohio Valley, and into the Northeast and Mid-Atlantic, with a low pressure system tracking through the region. A warm front will be draped across portions of the Ohio Valley and Mid-Atlantic during this time. As the cold front sweeps through by Thursday and Friday evenings, rain and thunderstorm activity will gradually shift eastward, with the front pushing off the Atlantic Coast by Friday. Rain will continue across the Northeast and portions of the Mid-Atlantic through Friday as the frontal system clears. Behind the front, drier conditions are expected to gradually return to the interior East.

Temperature Anomalies:
-Days 1-3: Temperatures will be above normal across the Great Lakes, Upper Midwest, and Northeast, with anomalies of 6 to more than 12 degrees above normal in some areas, particularly across the Upper Great Lakes and New England. Portions of the Mid-Atlantic and Southeast will be near normal. A small area of slightly below-normal temperatures is noted in parts of the Mid-Atlantic on Days 1 and 2.
-Days 4-6: Above-normal temperatures persist across the Great Lakes, Ohio Valley, Northeast, and Mid-Atlantic, with anomalies of 6 to over 12 degrees above normal in the Great Lakes and Northeast. The Southeast and southern portions of the East trend closer to normal.
-Days 7-10: Above-normal temperature signals gradually diminish across the East, with much of the region trending toward near-normal conditions. Slight above-normal anomalies may linger in portions of the Northeast and Mid-Atlantic into the end of the period.

CENTRAL:

The central United States will be the focal point for the most significant weather threats during the first half of the forecast period. On Day 1, rain and thunderstorms are widespread across the central and northern Plains, Midwest, and into the western Gulf Coast region. A notable severe thunderstorm threat exists today across portions of Nebraska, Kansas, Iowa, and Missouri, where conditions will be favorable for organized convection. Additionally, heavy rain and flash flooding is possible across portions of this same region. By Day 2, the severe thunderstorm threat shifts northward, with a significant area of severe weather potential across North Dakota, South Dakota, Minnesota, and Nebraska. Rain and thunderstorms will continue broadly across the central Plains and Midwest. A low pressure system over the central Plains will help organize and focus convective activity. On Day 3, severe thunderstorm potential continues, with the threat area encompassing Minnesota, Wisconsin, Iowa, and Kansas. Heavy rain and flash flooding potential is highlighted across portions of Kansas and Missouri on Day 3 as well. A cold front will push through the region by Thursday evening, with rain and thunderstorms continuing along and ahead of the boundary across the southern Plains and western Gulf Coast. By Friday, the frontal system will have pushed far enough east that drier conditions begin to return to much of the central Plains, though some rain and thunderstorm activity will linger near the western Gulf Coast.

Temperature Anomalies:
-Days 1-3: Temperatures will be above normal across much of the central Plains, Midwest, and into the northern Plains, with anomalies generally in the 3 to 9 degrees above normal range. The Pacific Northwest influence brings below-normal temperatures into portions of the northern Rockies and northern Plains by Days 2 and 3, with anomalies of 3 to 6 degrees below normal in Montana and Idaho.
-Days 4-6: Above-normal temperatures gradually retreat from the central Plains. Below-normal temperatures become more established across the northern Plains, Wyoming, Montana, and the Dakotas, with anomalies of 3 to 9 degrees below normal. Much of the southern Plains trends toward near-normal conditions.
-Days 7-10: Below-normal temperatures expand and deepen across the central Plains, northern Plains, and into portions of the central Rockies, with anomalies of 6 to over 12 degrees below normal in some areas, particularly across Wyoming, Colorado, Nebraska, and Kansas. This cold pattern becomes increasingly well-defined through the end of the forecast period.

WEST:

The western United States will see a mix of weather conditions through the forecast period. On Day 1, rain is occurring across portions of Washington and Oregon, with mixed precipitation — including snow — noted across parts of Idaho and Montana. Critical fire weather conditions are present across portions of Utah and Nevada, where dry and windy conditions will create elevated fire danger. Low pressure systems are positioned over the Pacific Northwest and the Desert Southwest. By Day 2, mixed precipitation continues across Idaho and Montana, and critical fire weather conditions persist across portions of Utah. Rain and thunderstorm activity will be present across portions of the Pacific Northwest. A low pressure system over the Southwest will continue to influence weather across that region. By Day 3, mixed precipitation expands across Washington, Idaho, and Montana, with rain and thunderstorm activity continuing across the Pacific Northwest. The Southwest low pressure system persists, with some rain and thunderstorm activity across the region. Through the latter part of the week, rain continues across the Pacific Northwest, while the interior West gradually sees decreasing precipitation coverage.

Temperature Anomalies:
-Days 1-3: Temperatures will be near normal across much of the Pacific Northwest and Pacific Coast on Day 1. By Days 2 and 3, below-normal temperatures develop across the Pacific Northwest, particularly Washington, Idaho, and Montana, with anomalies of 3 to 6 degrees below normal. Portions of the Southwest, southern Rockies, and California will be slightly above normal. A notable area of below-normal temperatures is centered over Montana and Idaho by Day 3, with anomalies of 6 to 9 degrees below normal.
-Days 4-6: Below-normal temperatures persist across the northern Rockies and northern Plains, gradually shifting southward. California, Nevada, Arizona, and the Southwest will see above-normal temperatures, with anomalies of 3 to 9 degrees above normal, particularly across California and Arizona by Days 5 and 6. The Pacific Northwest trends toward near-normal conditions by Day 6, with above-normal temperatures developing along the Oregon and Washington coasts.
-Days 7-10: Above-normal temperatures become well-established across the Pacific Coast, Pacific Northwest, and much of the Southwest, with anomalies of 6 to over 12 degrees above normal along the Oregon and Washington coasts. The interior West, including portions of Nevada, Utah, and Arizona, will also see above-normal temperatures. Below-normal temperatures will be confined to portions of the central Rockies and adjacent areas.

TROPICAL: Two Category 2 hurricanes are currently active in the Eastern Pacific basin, although neither storm is anticipated to impact the mainland US. In the Atlantic basin, no tropical cyclone activity is expected during the next seven days.