Tennis-ball sized hail and even one report of baseball-size hail pelted parts of the Twin Cities on Monday as thunderstorms rolled through the state.

"That's scary-sized hail," said Brent Hewett, a meteorologist for the National Weather Service in Chanhassen. "It doesn't happen often."

Hewett said the 4-inch hail was 2 miles southwest of Delano. "If you're out in the open, it could definitely hurt you," he said.

No injuries were reported.

Residents of the west and north metro posted photos on social media showing hail that shattered windshields and left large dents in cars. The NWS had warned the hail could injure people and animals or damage roofs, siding, windows and vehicles.

Hail that fell a few miles south of Delano measured 3 to 4 inches in size.

Casey Common, Star Tribune
A hailstone in Watertown today.

Mary Barthel, 27, had driven from St. Cloud to visit her parents in Watertown for the weekend. She was sitting in the house with her dad when the pair heard the hail start hitting the windows of the house.

It lasted about 10 minutes total and came in two rounds — the first was small and relatively harmless, but the second brought hail that smashed Barthel's car's sunroof and cracked the windshield.

The hail also ripped some window screens and made holes in the house's vinyl siding.

"And now the sun's out, and it's beautiful," Barthel said about an hour later. "I haven't seen hail quite that size in a long time."

Storms in the Walker area knocked trees onto power lines and damaged a billboard, said Bryan Howell, a meteorologist for the NWS in Duluth.

The storms subsided, and clear skies and more humidity were expected on Tuesday. Another chance for storms arrives early Wednesday morning.

A cold front stretching out over the state and moving south combined with heat and humidity in the area to cause the storms, said Tyler Hasenstein, also a meteorologist for the NWS.

A handful of counties in Minnesota, including Hennepin and Ramsey, were under a severe thunderstorm watch until Monday night. The threats were ramped up to warnings for the southern and western suburbs.

Staff writer Zoë Jackson contributed to this report.

Katie Galioto • 612-673-4478