NO. 21 WASHINGTON PRECIPITATION ABBOT AND McCANDLISH 3 



This study led to the arrangement shown in table 3, where sums are 

 given of the monthly percentages in the dates I to VII through the 



intervals indicated. Maxima are printed in bold-face type, minima 

 in italics. 



Table 2 — Yearly Sums of Monthly Percentages of Total Precipitation Falling on 

 Successive Days of the Week, 1924-1939 

 Successive Days 



Year I II III IV V VI VII 



1924 142 166 183 260 193 98 60 



1925 19 8 75 248 205 100 231 142 



1926 211 276 147 160 104 144 157 



1927 105 322 118 167 131 140 217 



1928 95 237 167 228 113 221 139 



1929 170 306 292 133 167 89 43 



J 930 151 51 3H 105 86 344 150 



1931 193 243 161 96 183 106 224 



1932 257 236 131 225 147 99 107 



1933 154 127 169 168 107 178 297 



1934 229 177 280 103 91 137 182 



1935 126 101 232 334 181 103 124 



1936 171 251 215 153 290 89 35 



1937 137 88 161 186 237 226 165 



1938 162 154 122 240 115 239 160 



1939 50 124 25 105 93 48 66 



Totals 2,551 2,934 2,965 2,868 2,338 2,492 2,268 



Jan. 



Nov. 



Oct. 



Dec. 



Nov. 



Jan. 



Apr. 



Jan. 



Dec. 



Dec. 



Apr. 



Jan. 



Jan. 



July 



Jan. 



Interval 

 1924-Oct. 

 1924-Sept. 

 1925-Nov. 

 1927-Oct. 

 1928-Dec. 

 1930-Mar. 

 1 93 1 -Dec. 

 1932-Nov. 

 1932-Nov. 

 1933-Mar. 

 1935-Dec 

 1936-Dec. 

 1937-June 

 1937-Dec. 

 1938-May 



1 



1924 103 



1925 203 



1927 349 



1928 64 



1929 202 



I93i 165 



I93i 179 



1932 257 



1933 149 



1935 265 



1935 95 



1936 171 



1937 3$ 



'937 99 



1939 212 



Table 



11 



157 



46 

 632 

 148 

 399 

 196 



98 

 193 

 165 

 232 



5i 

 251 



57 



3i 

 278 



in 



7i 

 342 



279 

 148 



315 

 402 



73 

 128 

 132 

 416 

 136 

 215 



4<> 

 121 



147 



IV 

 252 



196 



305 

 231 

 169 

 141 

 60 

 225 



125 

 203 

 277 

 153 

 93 

 93 

 345 



V 

 190 



74 

 258 

 112 



174 

 92 

 177 

 129 

 125 

 US 

 157 

 290 



133 

 104 

 208 



VI 



73 



135 



361 



258 



96 



35i 



99 



63 



214 



156 

 84 

 89 



154 



72 

 287 



VII 



55 



105 



415 



138 



45 



155 



219 



107 



290 



214 



99 



35 



85 



80 



226 



By reduction of table 3 to percentages there results table 4. 

 From table 4 we conclude that, assuming a periodicity of 6 days 

 18 hours in precipitation at Washington, a day of maximum precipi- 



