National Weather Service United States Department of Commerce

 

Normal Monthly Number of Days With Precipitation
of 0.5, 1.0, 2.0, and 4.0 Inches or More

These images were scanned from a copy of
TECHNICAL PAPER NO. 57
Normal Monthly Number of Days with Precipitation of 0.5, 1.0, 2.0, and 4.0 Inches of Rainfall or More in the Conterminous United States

(published in 1966)

This report provides, in a series of monthly maps, generalized estimates of the normal number of 24-hour periods with precipitation equal to or greater than 0.50, 1.00, 2.00, and 5.00 in.  Data used in this report are for the period 1931-60.  This period was selected to conform with the World Meteorological Organization standard for Climatological Normals.  For convenience, the word "days" is used interchangeably with the more precise term "24-hour periods."  In all cases, "days" should be thus interpreted and not confined to any other clock or calendar restriction.

 

Cover and Title Pages
COVER PREFACE PAGE 1 (Introduction) PAGE 2 PAGE 3 PAGE 4

 

Month-Rainfall Number of 24-hr Periods with 0.5" Number of 24-hr Periods with 1.0" Number of 24-hr Periods with 2.0" Number of 24-hr Periods with 4.0"
January January January January January
February February February February February
March March March March March
April April April April April
May May May May May
June June June June June
July July July July July
August August August August August
September September September September September
October October October October October
November November November November November
December December December December December