Millions of people in the southern Plains and western Gulf Coast states are at risk of experiencing severe weather conditions that could potentially obstruct views of Monday's total solar eclipse. According to forecasts, around 20 million people in Texas, Louisiana, Arkansas, and Oklahoma may be affected by multiple rounds of storms beginning Monday afternoon.

The primary threat during these storms is expected to be very large hail, posing a significant risk to the affected areas. As the week progresses, the threat will shift towards East Texas and Louisiana, with Texas experiencing the most significant impact. Major cities including Houston, Dallas, Austin, and San Antonio fall within the path of these storms.

In Dallas, storms are predicted to begin between 3 and 4 p.m. CT, slightly after the expected eclipse at around 1:30 p.m. CT. Meanwhile, in Kerrville and Junction, Texas, isolated storms are likely to start between 1 and 2 p.m. Although these storms may be in their early stages during the eclipse, they have the potential to bring large hail, damaging winds, isolated tornadoes, and frequent lightning to the Lone Star State.

The storms may also lead to a risk of severe weather, including flash flooding, across much of Texas on Tuesday. However, the precise timing and location of these storms remain uncertain, with trends suggesting that they are likely to occur after totality ends.

Adding to the unfavorable viewing conditions, low-, mid-, and high-level clouds are expected to increase on Monday ahead of the storms. Mid- and low-level clouds are projected to obstruct a larger portion of the eclipse compared to high-level clouds.

Regions where clouds may hinder the view of the eclipse include parts of Texas, southern Arkansas, Ohio, northwest Pennsylvania, and New York, according to the National Weather Service Weather Prediction Center. Along the eclipse path, there will likely be high cirrus clouds, which are thin and wispy. While these clouds may not completely obscure the view, they may appear as a thin mask or filter over the eclipse.

Cities such as Dallas, Kerrville, and Junction in Texas are forecasted to experience clouds at all levels, while places like Little Rock, Arkansas, and Indianapolis, Indiana, are expected to have mostly high clouds. Additionally, the village of Brockport in western New York is anticipated to have 69% low cloud cover and 87% mid cloud cover. Conversely, most of the East Coast, including states like Maine, are expected to have relatively clear skies, with minimal cloud cover at all levels.

As the eclipse approaches, individuals in the affected areas are encouraged to stay updated on weather conditions and any warnings issued by local authorities.