A series of thunderstorms that moved across the same region (called training) just after Midnight EDT on the 27th caused flash flooding of streams and poor drainage flooding in Somerset and Hunterdon Counties. The run-off from those thunderstorms and other thunderstorms later that morning caused flooding along some of the slower responding and/or larger streams and rivers in Mercer, Hunterdon, Somerset and Middlesex Counties. Doppler radar storm total estimates averaged between 1 and 4 inches across the four county area with the highest amounts in Hunterdon and Somerset Counties.

Flash Flood in HUNTERDON, NEW JERSEY
From 27-APR-07 02:20:00 to 27-APR-07 08:00:00 (EST-5)
Location: SERGEANTSVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Training thunderstorms with heavy rain entered Hunterdon County around Midnight EDT on the 27th and continued until around 3 a.m. EDT. Doppler Radar storm total estimates reached between 3 and 4 inches in a narrow band from Delaware Township northeast through Raritan and East Amwell Townships. This caused roadway and flash flooding of streams within that band and hit Delaware Township the hardest. About 14 roads in the township were flooded and closed including New Jersey State Route 29. Debris left behind by the flood waters had to be cleared from roadways and schools were closed for the day. Storm totals included 3.40 inches in Ringoes, 2.51 inches in Wertsville and 1.97 inches in Flemington.

Flood in MERCER, NEW JERSEY
From 27-APR-07 12:55:00 to 27-APR-07 14:55:00 (EST-5)
Location: TRENTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The run-off from the heavier rain that fell earlier in the day on the 27th caused minor flooding along the Assunpink Creek that afternoon. The Assunpink Creek in Trenton was above its 7 foot flood stage from 155 p.m. EDT through 355 p.m. EDT on the 27th. It crested at 7.08 feet at 3 p.m. EDT. Because of the buyout and removal of homes on Mulberry Street, as of May 1st, 2007 the flood stage of the Assunpink Creek at Trenton will be raised from 7 feet to 8.5 feet.
Storm totals included 2.09 inches in Washington Crossing. 1.90 inches in Trenton and 1.47 inches in Mercerville.

Flood in MIDDLESEX, NEW JERSEY
From 27-APR-07 09:00:00 to 27-APR-07 11:15:00 (EST-5)
Location: MIDDLESEX
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Run-off from heavier rain earlier in the morning caused the Bound Brook at Middlesex Borough to exceed its 9 foot flood stage from 10 a.m. EDT through 1215 p.m. EDT on the 27th. It crested at 9.09 feet at 11 a.m. EDT. Storm totals included 2.10 inches in Metuchen and 1.71 inches in New Brunswick.

Flash Flood in SOMERSET, NEW JERSEY
From 27-APR-07 02:10:00 to 27-APR-07 08:00:00 (EST-5)
Location: RARITAN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Training thunderstorms with heavy rain entered Somerset County between Midnight and 1 a.m. EDT on the 27th and continued until between 3 a.m. and 4 a.m. EDT. Doppler Radar storm total estimates reached between 3 and 4 inches in a band from Hillsborough and Branchburg Townships northeast through Somerville, Manville, Bridgewater, Bound Brook, Warren, Green Brook, North Plainfield and Watchung. This caused flash flooding of smaller streams in the early morning of the 27th and led to minor flooding along some of the larger rivers in the county later that day. In Hillsborough Township, a woman was rescued from the Raritan River after she drove around barricades and became caught in a flooded section of Somerset County Route 625 just before the John Basilone Veterans Memorial Bridge leading into Raritan Borough. During the early morning both U.S. Routes 206 and 202 were closed in Raritan Borough. There were a few voluntary evacuations in Green Brook. Two roads were closed.  U.S. Route 22 was among four roads closed in North Plainfield. One home was evacuated on Princeton Lane. In Bound Brook, the worst flooding was reported on Piedmont road, Windsor and Chestnut Streets and Linden Avenue. On the latter road, up to three feet of water was reported in basements. There were road closures also in Hillsborough and Franklin Townships. Six roads were closed in Hillsborough Township and schools had a two hour delayed opening. Northbound Interstate 287 north of milepost 16 near the South Bound Brook and Franklin Township border was closed to passenger vehicles during the early morning. Tractor-trailers were permitted to go through.
The Pike Run at Belle Mead was above its 7 foot flood stage from 717 a.m. through 815 a.m. EDT on the 27th. It crested at 7.21 feet at 745 a.m. EDT. The Green Brook at Plainfield (Union County) was above its 8 foot flood stage from 414 a.m. EDT through 815 a.m. EDT on the 27th. It crested at 9.75 feet at 6 a.m. EDT. The Stony Brook at North Plainfield was above its 7 foot flood stage from 338 a.m. EDT through 427 a.m. EDT on the 27th. It crested at 7.5 feet at 4 a.m. EDT. Farther downstream, the Stony Brook at Watchung was above its 14.5 foot flood stage from 314 a.m. through 451 a.m. EDT on the 27th. It crested at 15.9 feet at 4 a.m. EDT. The North Branch of the Raritan River at South Branch was above its 7 foot flood stage from 5 a.m. EDT through 716 p.m. EDT on the 27th. It crested at 9.64 feet at 1230 p.m. EDT.
Storm totals included 3.30 inches in Bound Brook, 2.73 inches in Watchung, 2.19 inches in Somerville, 2.03 inches in Basking Ridge and 1.94 inches in Hillsborough.

Flood in SOMERSET, NEW JERSEY
From 27-APR-07 08:00:00 to 28-APR-07 22:50:00 (EST-5)
Location: GRIGGSTOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Run-off from the heavy rain earlier in the morning caused flooding along some of the larger streams and rivers in Somerset County later in the day on the 27th into the 28th. Flooding was considerably less than what occurred along the Raritan and Millstone Rivers around April 16th.
The North Branch of the Raritan River at South Branch was above its 7 foot flood stage from 5 a.m. EDT through 716 p.m. EDT on the 27th. It crested at 9.64 feet at 1230 p.m. EDT. The main stem of the Raritan River at Bound Brook was above its 28 foot flood stage from 605 p.m. EFT through 825 p.m. EDT on the 27th. It crested at 28.07 feet at 715 p.m. EDT. The Millstone River at Griggstown was above its 10 foot flood stage from 1126 a.m. EDT on the 27th through 1150 p.m. EDT on the 28th. It crested at 12.05 feet at 1215 a.m. EDT on the 28th.
Storm totals included 3.30 inches in Bound Brook, 2.73 inches in Watchung, 2.19 inches in Somerville, 2.03 inches in Basking Ridge and 1.94 inches in Hillsborough.