High Pressure Continues

General Overview: ACTIVE WEATHER PATTERN ACROSS THE NATION WITH RAIN AND THUNDERSTORMS AFFECTING MULTIPLE REGIONS THROUGH MIDWEEK. SIGNIFICANT PRECIPITATION EXPECTED ACROSS THE NORTHERN PLAINS, UPPER MIDWEST, AND PORTIONS OF THE ROCKIES. COASTAL LOW PRESSURE SYSTEM WILL BRING RAIN TO THE MID-ATLANTIC AND NORTHEAST. ABOVE NORMAL TEMPERATURES WILL DOMINATE THE NORTHERN PLAINS AND UPPER MIDWEST.

EAST:  An area of low pressure will track along the East Coast through Tuesday, bringing rain and thunderstorms to coastal regions from the Carolinas northward through the Mid-Atlantic and into portions of the Northeast. The heaviest precipitation appears focused along the immediate coast, with rain spreading inland across portions of Virginia, Maryland, and the Delmarva Peninsula. By Tuesday evening, this coastal system will begin moving offshore, though some lingering moisture may continue to affect parts of New England. High pressure building in by midweek will bring drier conditions to much of the region, though another low pressure system may develop off the Mid-Atlantic coast by late week, potentially bringing additional rainfall to coastal areas.

Temperature Anomalies:

-Days 1-4: Near normal temperatures for most of the East, with slightly cooler conditions possible along the immediate coast where cloud cover and precipitation will be most persistent. Parts of the Northeast may see slightly above normal temperatures as high pressure builds in.

-Days 5-8: Generally near normal temperatures prevailing across the region, with some slight warming possible in the Ohio Valley and interior Northeast as the pattern stabilizes under high pressure influence.

-Days 9-10: Continued near normal temperatures with minimal anomalies across the Eastern states.

CENTRAL:  A significant weather system will affect the Central Plains and Upper Midwest through midweek, with widespread rain and thunderstorms stretching from the Dakotas southward through Nebraska, Kansas, and into portions of Oklahoma and Texas. The most organized precipitation will occur along and ahead of a cold front pushing through the region. By Tuesday, the system shifts eastward with rain and thunderstorms spreading into Minnesota, Iowa, and Missouri. Multiple low pressure centers will track through the region, maintaining unsettled conditions. By late week, a new frontal boundary will push through the Northern Plains and Upper Midwest, potentially bringing another round of precipitation to these areas.

Temperature Anomalies:

-Days 1-4: Significantly above normal temperatures across the Northern Plains and Upper Midwest, with anomalies of 6-12°F above normal, particularly in North Dakota, Minnesota, and parts of Wisconsin. Near normal temperatures elsewhere across the Central region.

-Days 5-8: Continued above normal temperatures across the Northern Plains gradually moderating, with warming spreading into portions of the Central Plains. By day 7-8, temperature anomalies become less pronounced across the region.

-Days 9-10: Near normal temperatures return to most of the Central states, with some slight above normal readings persisting in the Northern Plains and Upper Midwest.

WEST:  An active pattern will bring periods of precipitation to portions of the West, particularly across the Northern Rockies, Pacific Northwest, and parts of the Southwest. Areas of low pressure will track through the region, bringing rain to lower elevations and mixed precipitation to higher terrain. The Southwest will see scattered thunderstorm activity, particularly across Arizona and New Mexico. By midweek, high pressure builds over the Great Basin, bringing drier conditions to much of the interior West, though precipitation chances continue along the Pacific Northwest coast and Northern Rockies. California will see generally dry conditions with occasional coastal precipitation.

Temperature Anomalies:

-Days 1-4: Slightly above normal temperatures across much of the West begin to build in Tuesday, particularly in the Pacific Northwest and Northern Rockies where anomalies of 3-6°F above normal are expected.

-Days 5-8: Continued mild conditions with above normal temperatures persisting across the Northwest and Northern Rockies, gradually moderating by day 8.

-Days 9-10: Near normal to slightly above normal temperatures across most of the West, with the warmest anomalies focused in the Northern Rockies and Pacific Northwest.

TROPICAL: Tropical Storm Mario is noted in the eastern Pacific off the coast of Mexico. The system appears to be tracking northwestward away from land and does not pose an immediate threat to the continental United States. A tropical wave over the central tropical Atlantic is producing a large area of disorganized showers and thunderstorms. Although dry and stable air is expected to limit development during the next day or so, gradual development is anticipated thereafter, and a tropical depression is likely to form by the middle to latter part of this week as the system moves west-northwestward at 10 to 15 mph over the central tropical Atlantic. No tropical impacts expected through the period for the US. 
Formation chance through 48 hours…low…30 percent.
Formation chance through 7 days…high…80 percent.