The Annual March of Temperature at Washington, D. C.*

Abstract

A number of diagrams are shown, contrasting day-by-day average temperatures at Washington with the accepted “normals”, showing extreme highest and lowest temperatures for each day of the year, the “January Thaw,” a recurrent cold period in February, an estimation of the potentially highest and lowest temperatures at Washington, and recent abnormal temperature trends are discussed. The annual day-by-day march of degree days for heating is also noted. The results in general suggest some revision of the popular conception of “normals” is in order.

Correspondence

“…A paper by Slocum appearing in 1941 [5] was used by Wahl as justification for further delineation of the January Thaw. Actually Roscoe Nunn had adopted a synoptic approach in 1927 [6] on this well-known singularity, and had typed the Lows appearing on daily surface charts in the period 1901-1927 which had dominated the mild spells noted and graphed by him at Baltimore.…”

Trends and singularities in the mean temperature‐data of Saint‐Louis, Missouri

“…SLOCUM [8] in 1941, in attempting to interpret the fluctuating character of the mean tempera ture-curve of Washington, D. C, at the time of the minimum, added new evidence for the reality of the January Thaw. In his analysis he used a different approach from that of NUNN [9] in his study in 1927 of the January Thaw.…”