The weather pattern the first few days of July will result in largely July-like temperatures for much of the country along and east of the Rockies.
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Daytime highs will largely be close to seasonal on average, but the hottest temperatures versus normal will initially reside from the Southern Plains to the Northeast on Friday.
Then, with each passing day this weekend and leading up to the Fourth of July, temperatures will heat up gradually throughout the Heartland and east to the Ohio Valley.
An upper trough traversing southern Canada through the weekend will usher a pair of cold fronts across the far northern extent of the Lower 48, resulting in seasonally cooler temperatures from North Dakota and the northern Great Lakes to northern New England this upcoming weekend and leading into July Fourth.
The coolest temperature anomalies will be centered along the West Coast as a large upper trough moves ashore late Sunday into Monday.
Daytime high temp anomalies by Independence Day are forecast to be as cool as 10-20 degrees below normal with some of the higher elevations of the Cascades struggling to get out of the 50s.
In the South, temperatures will generally be slightly below normal, but the lingering humid air-mass in place will still result in typical "dog days of Summer" heat indices in the mid-upper 90s and occasionally into the triple digits this weekend.
In terms of areas of precipitation looking to put a damper on holiday weekend travel and activities, the classic summer pattern in place will result in diurnally-driven shower and thunderstorms activity across the South and much of the Heartland.
Along the Upper Texas Coast, an approaching tropical wave is continuing to generate heavy rain and embedded thunderstorms this afternoon.
A Slight Risk (threat level 2/4) of Excessive Rainfall is in place for the Upper Texas coast today with another Slight Risk for the Upper Texas coast and southwest Louisiana on Friday.
A rich moisture source throughout the South will provide thunderstorms plenty of opportunities to produce torrential downpours that could result in localized flash flooding, as well as potentially rain on some July Fourth parades at times this weekend.
Severe weather potential will be highest along passing frontal boundaries.
Today, a cold front sweeping through the Upper Mississippi Valley may lead to severe storms in parts of the region this afternoon and evening.
By Friday, the cold front will track towards the northern Mid-Atlantic and extend as far south and west as the Central Plains.
The best chances for severe weather reside in the Black Hills and portions of northern Nebraska and eastern Wyoming where the SPC has a Slight Risk (threat level 2/5) in place.
By Saturday, the cold front will race towards the Northeast with organized severe weather possible along the I-95 corridor from D.C. to Boston.
The SPC also has a Slight Risk in parts of the major I-95 corridor of the Northeast on Saturday with damaging winds and large hail possible.
Strong-to-severe storms are may develop from the Mid-South to the southern Mid-Atlantic on Sunday.
Farther west, monsoonal flow into the Southwest will keep plenty of atmospheric moisture around this afternoon and through the upcoming weekend.
Daily rounds of showers and storms will dot parts of the Desert Southwest, southern and central Rockies, and the central High Plains containing heavy downpours and occasionally gusty winds.
Localized flash flooding is possible, particularly in areas that have received heavy amounts of rainfall in recent weeks and near burn scars.
In the Northwest, the approaching upper trough will trigger scattered showers and storms from the Cascades to the northern Rockies on Sunday with some storms potentially becoming severe. ■