Showers and Storms Across the Region

General Overview: WIDESPREAD RAIN AND THUNDERSTORMS EXPANDING ACROSS THE EASTERN THIRD OF THE COUNTRY TODAY. MIXED PRECIPITATION EXPECTED IN THE NORTHERN ROCKIES AND PORTIONS OF THE PACIFIC NORTHWEST THROUGH EARLY NEXT WEEK. ABOVE NORMAL TEMPERATURES ACROSS THE MIDWEST AND GREAT LAKES WILL GRADUALLY SHIFT WESTWARD.

EAST: Impactful weather arrives Sunday as a low pressure system moves northeastward, bringing widespread rain and thunderstorms from the Gulf Coast through the entire Eastern Seaboard. Some thunderstorm activity may continue along coastal areas into Monday.

By Monday into Tuesday, precipitation will begin to diminish as high pressure builds in from the Southeast. The Northeast will see lingering rain showers Monday with a new low pressure system developing near New England by Tuesday. This system will bring additional rainfall to parts of the Northeast and coastal areas. By midweek, conditions should gradually improve across most of the region as the weather pattern stabilizes.

Temperature Anomalies:

-Days 1-3: Significantly above normal temperatures across much of the region, particularly in the Northeast and Mid-Atlantic where temperatures will run 6-12°F above normal. The Southeast will experience near to slightly above normal temperatures.

-Days 4-6: Temperatures will moderate closer to seasonal norms across most areas. The Southeast and coastal regions may experience slightly below normal temperatures, while the interior Northeast remains slightly above normal.

-Days 7-10: Near normal temperatures for most of the region, with some slightly below normal readings possible in the Southeast and slightly above normal conditions returning to the northern portions of the region.

CENTRAL: By Sunday, the severe threat diminishes as the system shifts eastward, though rain and thunderstorms will continue across the eastern portions of the region. High pressure builds into the Central Plains by Monday, bringing drier conditions to much of the area. A new frontal boundary will approach from the northwest by Tuesday, bringing rain to portions of the Upper Midwest and Great Lakes region.

Temperature Anomalies:

-Days 1-3: Significantly above normal temperatures across the Midwest and Great Lakes, with readings 6-12°F above normal. Near normal temperatures across the Southern Plains.

-Days 4-6: Temperatures will moderate closer to seasonal norms for most areas, with slightly below normal readings developing across portions of the Tennessee Valley and lower Ohio Valley. The Northern Plains will begin to see above normal temperatures.

-Days 7-10: A warming trend develops across the Northern Plains and Upper Midwest with temperatures 6-12°F above normal. Near normal temperatures elsewhere, with some slightly above normal readings in the Southern Plains.

WEST:  The Western region will experience a mix of precipitation types over the coming days. Mixed precipitation including snow will affect portions of the Northern Rockies and Pacific Northwest through the weekend. Areas of Wyoming, Montana, and Idaho will see the most significant mixed precipitation. The Southwest will remain generally dry with high pressure dominating.

By Monday and Tuesday, precipitation will diminish across much of the region as high pressure builds. However, a new system approaching the Pacific Northwest by midweek will bring additional rain and mountain snow to Washington and Oregon. The Southwest will see continued dry conditions with areas of low pressure developing in California by Tuesday.

Temperature Anomalies:

-Days 1-3: Near to slightly below normal temperatures across the Pacific Northwest and Northern Rockies. Near normal temperatures elsewhere.

-Days 4-6: Warming trend begins across the interior West with temperatures climbing to 3-6°F above normal in many areas. The Pacific Northwest will see near normal temperatures.

-Days 7-10: Continued above normal temperatures across much of the interior West and Northern Rockies, with readings 6-10°F above normal in Montana and the Dakotas. Below normal temperatures developing along the Pacific Coast, particularly in California and Oregon.

TROPICAL: 
ATLANTIC: Tropical development is possible in the Caribbean in the next 7 days as a tropical wave shifts west past the Antilles. 

EAST PACIFIC: A disturbance located offshore Guatemala will continue to move westward into the Pacific Ocean. There is a low chance of development over the next 7 days, but a system may yet materialize beyond 7 days.