Low pressure tracking toward southern New England tapped into a plume of tropical moisture and produced torrential rainfall over parts of central and northeast Massachusetts in the matter of a few hours. This resulted in prolific urban flash flooding in the greater Worcester area and significant urban flooding in greater Boston. The highest single rainfall total from this event was within the City of Worcester, where a Skywarn Spotter reported 5.24 inches of rainfall.

Flash Flood in MIDDLESEX, MASSACHUSETTS
From 21-OCT-16 19:52:00 to 21-OCT-16 20:50:00 (EST-5)
Location: WAYLAND
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Two to four inches of rain fell in the matter of a few hours on the evening of October 21 and resulted in significant urban flash flooding in Wayland. Many roads were flooded and impassable including parts of Routes 20, 27, 30, and 126, East Plain and School Streets, and Windy Hill Lane near Country Club and Storm Bridge Road. Old Connecticut Path near Wayland High School was flooded with water reaching the tops of car tires. A car was stuck in flood waters at the intersection of Pequot Road and Happy Hollow Road. No injuries were reported.

Flash Flood in WORCESTER, MASSACHUSETTS
From 21-OCT-16 17:58:00 to 21-OCT-16 19:55:00 (EST-5)
Location: FITCHBURG
Flood cause: Heavy Rain
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Three to five inches of rain fell within the matter of a few hours during the evening of October 21 which resulted in prolific urban flash flooding in Worcester and surrounding areas.
In Worcester, flash flooding made roads impassable and there were many reports of cars stuck in floodwaters and people needing rescue. Roads flooded included Cambridge, Chandler, Bancroft, Park, Harding, Hammond, Highland, Summer, Lincoln, Green, Grove, Bridge, Irving and Ellsworth Streets, as well as Goldthwaite Road, Pleasant Terrace, Major Taylor Boulevard, Shore Drive, and Park Avenue. One portion of Cambridge Street near Kansas Street was reported to be flooded with water 7 feet deep! MLK Boulevard flooded up to an underpass bridge in a low lying area. Several other streets were reported to have floodwaters over 4 feet deep, including Country Club Boulevard. Over 20 cars were reported stuck in floodwaters at the intersection of Highland Street and Park Avenue. Plantation Street from Oakhurst Street to I-290 was flooded with water up to 4 feet deep. Significant flooding was also reported on 122A as well as I-290, with floodwaters up to SUV tire height reported. Several vehicles were stuck in floodwaters on I-290.
In Fitchburg, flash flooding closed a section of the John Fitchburg Highway and a car was stuck in flood waters on Shelley Avenue.  In Leominster, flash flooding closed the intersection of Washington Street and Grove Avenue as well as McKay Street entering the hospital. In Lancaster, Main Street was flooded and impassable while in Shrewsbury, Route 9 at Oak Street was flooded up to the tops of car tires.
No injuries were reported due to the flash flooding.
Due to the ongoing drought conditions, stream and river flows were well below average and the excessive amount of rainfall did not produce flooding.

Flash Flood in ESSEX, MASSACHUSETTS
From 21-OCT-16 21:01:00 to 21-OCT-16 22:15:00 (EST-5)
Location: METHUEN
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Two to three inches of rain fell in only a couple of hours and produced significant urban flash flooding. In Methuen, Riverside Drive by the boat ramp was closed due to flooding and several cars were stranded. Route 213 at I-495 was flooded and cars were stuck in the roadway. In Haverhill, the area near Laurel and Railroad Avenues was flooded with four feet of water and a car was stranded in flood waters. The intersection of Primrose and Dexter Avenues was impassable. In Peabody, several roads were impassable due to flooding which included Allens Lane, Walnut Street, Prospect Street near the North Shore Mall, Foster Street, Tremont Street,  and Margin Street. In Danvers, Wildwood Road was flooded. In Lynn, a portion of Boston Street was flooded.

Flash Flood in SUFFOLK, MASSACHUSETTS
From 21-OCT-16 21:06:00 to 21-OCT-16 22:00:00 (EST-5)
Location: BACK BAY ANNEX
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Two to three inches of rain in a short time produced significant urban flash flooding in and around Boston. Two people were rescued from a car stuck in two feet of flood waters on Malcolm X Boulevard in Boston, while flooding also closed a portion of Columbia Road near I-93. Flooding also affected the Alewife T Station. In Chelsea, flooding was reported on Everett Avenue from the high school and on Beech Street. In Mattapan, a section of Harvard Street was flooded between Walk Hill and Morton Streets.

Flash Flood in ESSEX, MASSACHUSETTS
From 21-OCT-16 21:06:00 to 21-OCT-16 22:06:00 (EST-5)
Location: SAUGUS IRON WORKS NH
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Two to three inches of rain which fell in a matter of hours produced significant urban flash flooding. In Lexington, a portion of Lincoln Street was flooded from Lincoln fields to the intersection with Route 2A. In Belmont, Common Street was closed due to flooding near Royal Road. In Waltham, two cars were stuck in flood waters on South Street near the intersection with Sunnyside Street. In Everett, people were trapped inside their cars due to flooding on Vale Street. No injuries were reported.