Tropical Storm Calvin bringing strong winds and torrential rain to the Big Island

Tropical Storm Calvin was bringing heavy rain to Hawaii's Big Island on Wednesday.

Packing winds of 45 mph, Calvin was about 205 miles southwest of Hilo on Wednesday morning, according to an update from the National Hurricane Center.

The storm is delivering strong winds and heavy rainfall that could result in flash flooding and mudslides. Calvin is expected to remain a tropical storm for another 24 hours before weakening.

"Calvin has almost completed its passage south of Hawaii County," the hurricane center said. "Expect periods of flash flooding, dangerous surf and damaging winds. Calvin will continue to weaken as it moves westward to the south of the other Hawaiian Islands today and tonight, bringing the potential for some peripheral impacts."

Between 4 and 8 inches of rain is expected, with some areas seeing up to 10 inches, mainly along the windward and southeast flank of the island of Hawaii, colloquially known as the Big Island.

Rainfall of 3 to 6 inches is expected on the windward areas of Maui, and 2 to 4 inches of rain could fall elsewhere in the state.

Gov. Josh Green declared a state of emergency Tuesday for the Big Island, where government offices are expected to close Wednesday.

"Non-essential employees affected by the closing of those offices should not report to work and shall be granted Administrative Leave," the governor's office said.

Swells generated by Calvin spread across the main Hawaiian islands Tuesday night into Wednesday, leading to a rapid increase in surf along east-facing shores. This elevated surf will likely cause life-threatening conditions along exposed shorelines.

CNN's Andy Rose and Taylor Ward contributed to this report.