The Waltham plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
Mostly sunny
Mostly sunny; warmer
Mostly sunny
Partly cloudy
Partly cloudy
Partly cloudy
Showers likely
73° on Nov. 13, 1999, the hottest reading for this week of the year since 1937. Next is 73° in 2012.
Waltham’s center stands about 1,320 ft above sea level. Within three miles the land runs from 1,260 ft to 1,370 ft, a difference of 110 ft: gently rolling country.
Under the town center the state geologic map shows Middle Devonian (dolostone, limestone, shale), from the Middle Devonian, 384 to 394 million years old.
The section below crosses 2 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone, limestone, shale. Age: Middle Devonian, 384 to 394 million years old. About 20 mi of the line.
Limestone, dolostone. Age: Late Ordovician, 445 to 459 million years old. About 4 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Waltham reaches the Gulf of America by way of Roberts Creek, the Cedar River, the Iowa and the Mississippi: about 1,750 river miles.
1,410 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Waltham; river miles along the main stem, rounded.
Waltham has a warm-summer humid continental climate. Summer afternoons average 81° in July; winter nights fall to about 5° in January. A normal year brings about 43 inches of snow; with the rain, that comes to about 36 inches of water.
On November 14 Waltham normally reaches 42° and falls to 25°. The record high is 69°, in 1964; the record low −10°, in 1959. The most rain on this date, 0.37 in, fell in 1973.
Normals 1991–2020 and records since 1937 at Austin Waste Water Treatment Facility, 13 miles south-southwest, 120 ft lower. NOAA, through RCC-ACIS.
