July 12 (Reuters) - Online spending soared $24.1 billion

across U.S. retailers during the stretch from July 8 to 11 -

dubbed "Black Friday in Summer", outpacing Adobe Analytics'

prior forecast, as eager shoppers rushed to snap up deep

discounts on back-to-school essentials.

Retailers recorded online sales growth of 30.3% during

events that included Amazon Prime Day, Adobe said on Saturday,

compared with its projections of 28.4%.

Online retail sales in the U.S. rose 11% to $14.2 billion a

year ago.

The Prime Day event has also been cemented as a

"back-to-school" shopping moment, as consumers jumped on early

deals to stock up on essentials and get ahead of the

back-to-school rush, Adobe said.

Several major retailers including e-commerce giant

Amazon.com ( AMZN ), Walmart ( WMT ), Target ( TGT ) as well as

Best Buy ( BBY ) have been launching deal events with strong

discounts, encouraging shoppers to trade up on expensive items

they might normally pass on.

Amazon.com ( AMZN ) extended its sales window to 96 hours, up from

the typical 48, featuring aggressive promotions on categories

ranging from apparel to electronics.

A wave of enticing deals comes at a time when heightened

trade tensions amid the Trump administration's volatile tariff

policies have rattled consumers and businesses, and as the new

August 1 deadline for countries to renegotiate trade agreements

with the United States looms.

According to the report, shopping on mobile was the dominant

transaction channel during the Prime Day event, driving 53.2% of

online sales, above Adobe's forecast of 52.5%.

According to Adobe, overall discounts across U.S. retailers

were between 11% and 24%, compared with the prior forecast range

of 10% to 24%.

Apparel had the biggest deals at 24%, compared with 20% last

year, while electronics were at 23%, similar to last year.