APPENDIX A:  TABLES
 
 
 | 
TABLE A-1   PROPERTIES OF WATER IN SI UNITS. |  
Temperature (°C) | 
Specific Gravity | 
Density (g/cm3) | 
Heat of Vaporization (cal/g) | 
Viscosity | 
Vapor Pressure |  
Absolute (cp) | 
Kinematic (cs) | 
(mm Hg) | 
(mb) | 
(g/cm2) | 
 
| 0 | 
0.99987 | 
0.99984 | 
597.3 | 
1.790 | 
1.790 | 
4.58 | 
6.11 | 
6.23 | 
 
| 5 | 
0.99999 | 
0.99996 | 
594.5 | 
1.520 | 
1.520 | 
6.54 | 
8.72 | 
8.89 | 
 
| 10 | 
0.99973 | 
0.99970 | 
591.7 | 
1.310 | 
1.310 | 
9.20 | 
12.27 | 
12.51 | 
 
| 15 | 
0.99913 | 
0.99910 | 
588.9 | 
1.140 | 
1.140 | 
12.78 | 
17.04 | 
17.38 | 
 
| 20 | 
0.99824 | 
0.998211 | 
586.0 | 
1.000 | 
1.000 | 
17.53 | 
23.37 | 
23.83 | 
 
| 25 | 
0.99708 | 
0.99705 | 
583.2 | 
0.890 | 
0.893 | 
23.76 | 
31.67 | 
32.20 | 
 
| 30 | 
0.99568 | 
0.99565 | 
580.4 | 
0.798 | 
0.801 | 
31.83 | 
42.43 | 
43.27 | 
 
| 35 | 
0.99407 | 
0.99404 | 
577.6 | 
0.719 | 
0.723 | 
42.18 | 
56.24 | 
57.34 | 
 
| 40 | 
0.99225 | 
0.99222 | 
574.7 | 
0.653 | 
0.658 | 
55.34 | 
73.78 | 
75.23 | 
 
| 50 | 
0.98807 | 
0.98804 | 
569.0 | 
0.547 | 
0.554 | 
92.56 | 
123.40 | 
125.83 | 
 
| 60 | 
0.98323 | 
0.98320 | 
563.2 | 
0.466 | 
0.474 | 
149.46 | 
199.26 | 
203.19 | 
 
| 70 | 
0.97780 | 
0.97777 | 
557.4 | 
0.404 | 
0.413 | 
233.79 | 
311.69 | 
317.84 | 
 
| 80 | 
0.97182 | 
0.97179 | 
551.4 | 
0.355 | 
0.365 | 
355.28 | 
473.67 | 
483.01 | 
 
| 90 | 
0.96534 | 
0.96531 | 
545.3 | 
0.315 | 
0.326 | 
525.89 | 
701.13 | 
714.95 | 
 
| 100 | 
0.95839 | 
0.95836 | 
539.1 | 
0.282 | 
0.294 | 
760.00 | 
1013.25 | 
1033.23 | 
 
 
| 
Source:  Linsley, R. K. et al. (1982). Hydrology for Engineers. 3d. ed., New York: McGraw-Hill.
 |   
 
 | 
TABLE A-2   PROPERTIES OF WATER IN U.S. CUSTOMARY UNITS. |  
Temperature (°F) | 
Specific Gravity | 
Density (lb/ft3) | 
Heat of Vaporization (Btu/lb) | 
Viscosity 1 | 
Vapor Pressure |  
Absolute (lbs/ft2) | 
Kinematic (ft2/s) | 
(in Hg) | 
(mb) | 
(lb/in2) | 
 
| 32 | 
0.99986 | 
62.418 | 
1075.5 | 
3.746 | 
1.931 | 
0.180 | 
6.11 | 
0.089 | 
 
| 40 | 
0.99998 | 
62.426 | 
1071.0 | 
3.229 | 
1.664 | 
0.248 | 
8.39 | 
0.122 | 
 
| 50 | 
0.99971 | 
62.409 | 
1065.3 | 
2.735 | 
1.410 | 
0.362 | 
12.27 | 
0.178 | 
 
| 60 | 
0.99902 | 
62.366 | 
1059.7 | 
2.359 | 
1.217 | 
0.522 | 
17.66 | 
0.256 | 
 
| 70 | 
0.99798 | 
62.301 | 
1054.0 | 
2.050 | 
1.058 | 
0.739 | 
25.03 | 
0.363 | 
 
| 80 | 
0.99662 | 
62.216 | 
1048.4 | 
1.799 | 
0.930 | 
1.032 | 
34.96 | 
0.507 | 
 
| 90 | 
0.99497 | 
62.113 | 
1042.7 | 
1.595 | 
0.826 | 
1.422 | 
48.15 | 
0.698 | 
 
| 100 | 
0.99306 | 
61.994 | 
1037.1 | 
1.424 | 
0.739 | 
1.933 | 
65.47 | 
0.950 | 
 
| 120 | 
0..98856 | 
61.713 | 
1025.6 | 
1.168 | 
0.609 | 
3.448 | 
116.75 | 
1.693 | 
 
| 140 | 
0.98321 | 
61.379 | 
1014.0 | 
0.981 | 
0.514 | 
5.884 | 
199.26 | 
2.890 | 
 
| 160 | 
0.97714 | 
61.000 | 
1002.2 | 
0.838 | 
0.442 | 
9.656 | 
326.98 | 
4.742 | 
 
| 180 | 
0.97041 | 
60.580 | 
990.2 | 
0.726 | 
0.386 | 
15.295 | 
517.95 | 
7.512 | 
 
| 200 | 
0.96306 | 
60.121 | 
977.9 | 
0.637 | 
0.341 | 
23.468 | 
794.72 | 
11.526 | 
 
| 212 | 
0.95837 | 
59.828 | 
970.3 | 
0.593 | 
0.319 | 
29.921 | 
1013.25 | 
14.696 | 
 
 
1 To obtain values of viscosity, multiply values shown in Table by 10-5.
 
Source:  Linsley, R. K. et al. (1982). Hydrology for Engineers. 3d. ed., New York: McGraw-Hill.
 |   
 
 | 
TABLE A-3   FACTOR p IN BLANEY-CRIDDLE METHOD.1 |  
Latitude North South | 
  Jan July | 
  Feb Aug | 
  Mar Sep | 
  Apr Oct | 
  May Nov | 
  Jun Dec | 
  Jul Jan | 
  Aug Feb | 
  Sep Mar | 
  Oct Apr | 
  Nov May | 
  Dec Jun |  
| 60° | 
0.15 | 
0.20 | 
0.26 | 
0.32 | 
0.38 | 
0.41 | 
0.40 | 
0.34 | 
0.28 | 
0.22 | 
0.17 | 
0.13 | 
 
| 50° | 
0.19 | 
0.23 | 
0.27 | 
0.31 | 
0.34 | 
0.36 | 
0.35 | 
0.32 | 
0.28 | 
0.24 | 
0.20 | 
0.18 | 
 
| 40° | 
0.22 | 
0.24 | 
0.27 | 
0.30 | 
0.32 | 
0.34 | 
0.33 | 
0.31 | 
0.28 | 
0.25 | 
0.22 | 
0.21 | 
 
| 30° | 
0.24 | 
0.25 | 
0.27 | 
0.29 | 
0.31 | 
0.32 | 
0.31 | 
0.30 | 
0.28 | 
0.26 | 
0.24 | 
0.23 | 
 
| 20° | 
0.25 | 
0.26 | 
0.27 | 
0.28 | 
0.29 | 
0.30 | 
0.30 | 
0.29 | 
0.28 | 
0.26 | 
0.25 | 
0.25 | 
 
| 10° | 
0.26 | 
0.27 | 
0.27 | 
0.28 | 
0.28 | 
0.29 | 
0.29 | 
0.28 | 
0.28 | 
0.27 | 
0.26 | 
0.26 | 
 
| 0° | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
0.27 | 
 
 
| 
1 p = [(mean daily daytime hours for a given month) / (total daytime hours in a year)] × 100
 |   
 
 | 
TABLE A-4   FACTOR K IN THORNTHWAITE METHOD.1 |  
| Latitude | 
Jan | 
Feb | 
Mar | 
Apr | 
May | 
Jun | 
Jul | 
Aug | 
Sep | 
Oct | 
Nov | 
Dec |  
| 60°N | 
0.54 | 
0.67 | 
0.97 | 
1.19 | 
1.33 | 
1.56 | 
1.55 | 
1.33 | 
1.07 | 
0.84 | 
0.58 | 
0.48 | 
 
| 50°N | 
0.71 | 
0.84 | 
0.98 | 
1.14 | 
1.28 | 
1.36 | 
1.33 | 
1.21 | 
1.06 | 
0.90 | 
0.76 | 
0.68 | 
 
| 40°N | 
0.80 | 
0.89 | 
0.99 | 
1.10 | 
1.20 | 
1.25 | 
1.23 | 
1.15 | 
1.04 | 
0.93 | 
0.83 | 
0.78 | 
 
| 30°N | 
0.87 | 
0.93 | 
1.00 | 
1.07 | 
1.14 | 
1.17 | 
1.16 | 
1.11 | 
1.03 | 
0.96 | 
0.89 | 
0.85 | 
 
| 20°N | 
0.92 | 
0.96 | 
1.00 | 
1.05 | 
1.09 | 
1.11 | 
1.10 | 
1.07 | 
1.02 | 
0.98 | 
0.93 | 
0.91 | 
 
| 10°N | 
0.97 | 
0.98 | 
1.00 | 
1.03 | 
1.05 | 
1.06 | 
1.05 | 
1.04 | 
1.02 | 
0.99 | 
0.97 | 
0.96 | 
 
| 0° | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
1.00 | 
 
| 10°S | 
1.05 | 
1.04 | 
1.02 | 
0.99 | 
0.97 | 
0.96 | 
0.97 | 
0.98 | 
1.00 | 
1.03 | 
1.05 | 
1.06 | 
 
| 20°S | 
1.10 | 
1.07 | 
1.02 | 
0.98 | 
0.93 | 
0.91 | 
0.92 | 
0.96 | 
1.00 | 
1.05 | 
1.09 | 
1.11 | 
 
| 30°S | 
1.16 | 
1.11 | 
1.03 | 
0.96 | 
0.89 | 
0.85 | 
0.87 | 
0.93 | 
1.00 | 
1.07 | 
1.14 | 
1.17 | 
 
| 40°S | 
1.23 | 
1.15 | 
1.04 | 
0.93 | 
0.83 | 
0.78 | 
0.80 | 
0.89 | 
0.99 | 
1.10 | 
1.20 | 
1.25 | 
 
| 50°S | 
1.33 | 
1.19 | 
1.05 | 
0.89 | 
0.75 | 
0.68 | 
0.70 | 
0.82 | 
0.97 | 
1.13 | 
1.27 | 
1.36 | 
 
 
| 
1 K = Constant to correct PET for latitudes other than 0° (Eq. 2-46).
 |   
 
 | 
  TABLE A-5   VALUES OF F (z) (AREAS UNDER HALF OF THE NORMAL PROBABILITY DENSITY FUNCTION, Eq. 6-11) VERSUS FREQUENCY FACTOR z 
(DOUBLE-ENTRY TABLE).  |  
| z | 
0.00 | 
0.01 | 
0.02 | 
0.03 | 
0.04 | 
0.05 | 
0.06 | 
0.07 | 
0.08 | 
0.09 | 
 
| 0.0 | 
0.0000 | 
0.0040 | 
0.0080 | 
0.0120 | 
0.0159 | 
0.0199 | 
0.0239 | 
0.0279 | 
0.0319 | 
0.0359 | 
 
| 0.1 | 
0.0398 | 
0.0438 | 
0.0478 | 
0.0517 | 
0.0557 | 
0.0596 | 
0.0636 | 
0.0675 | 
0.0714 | 
0.0753 | 
 
| 0.2 | 
0.0793 | 
0.0832 | 
0.0871 | 
0.0910 | 
0.0948 | 
0.0987 | 
0.1026 | 
0.1064 | 
0.1103 | 
0.1141 | 
 
| 0.3 | 
0.1179 | 
0.1217 | 
0.1255 | 
0.1293 | 
0.1331 | 
0.1368 | 
0.1406 | 
0.1443 | 
0.1480 | 
0.1517 | 
 
| 0.4 | 
0.1554 | 
0.1591 | 
0.1628 | 
0.1664 | 
0.1700 | 
0.1736 | 
0.1772 | 
0.1808 | 
0.1844 | 
0.1879 | 
 
| 0.5 | 
0.1915 | 
0.1950 | 
0.1985 | 
0.2019 | 
0.2054 | 
0.2088 | 
0.2123 | 
0.2157 | 
0.2190 | 
0.2224 | 
 
| 0.6 | 
0.2257 | 
0.2291 | 
0.2324 | 
0.2357 | 
0.2389 | 
0.2422 | 
0.2454 | 
0.2486 | 
0.2518 | 
0.2549 | 
 
| 0.7 | 
0.2580 | 
0.2611 | 
0.2642 | 
0.2673 | 
0.2704 | 
0.2734 | 
0.2764 | 
0.2794 | 
0.2823 | 
0.2852 | 
 
| 0.8 | 
0.2881 | 
0.2910 | 
0.2939 | 
0.2967 | 
0.2995 | 
0.3023 | 
0.3051 | 
0.3078 | 
0.3106 | 
0.3133 | 
 
| 0.9 | 
0.3159 | 
0.3186 | 
0.3212 | 
0.3238 | 
0.3264 | 
0.3289 | 
0.3315 | 
0.3340 | 
0.3365 | 
0.3389 | 
 
| 1.0 | 
0.3413 | 
0.3438 | 
0.3461 | 
0.3485 | 
0.3508 | 
0.3531 | 
0.3554 | 
0.3577 | 
0.3599 | 
0.3621 | 
 
| 1.1 | 
0.3643 | 
0.3665 | 
0.3686 | 
0.3708 | 
0.3729 | 
0.3749 | 
0.3770 | 
0.3790 | 
0.3810 | 
0.3830 | 
 
| 1.2 | 
0.3849 | 
0.3869 | 
0.3888 | 
0.3907 | 
0.3925 | 
0.3944 | 
0.3962 | 
0.3980 | 
0.3997 | 
0.4015 | 
 
| 1.3 | 
0.4032 | 
0.4049 | 
0.4066 | 
0.4082 | 
0.4099 | 
0.4115 | 
0.4131 | 
0.4147 | 
0.4162 | 
0.4177 | 
 
| 1.4 | 
0.4192 | 
0.4207 | 
0.4222 | 
0.4236 | 
0.4251 | 
0.4265 | 
0.4279 | 
0.4292 | 
0.4306 | 
0.4319 | 
 
| 1.5 | 
0.4332 | 
0.4345 | 
0.4357 | 
0.4370 | 
0.4382 | 
0.4394 | 
0.4406 | 
0.4418 | 
0.4430 | 
0.4441 | 
 
| 1.6 | 
0.4452 | 
0.4463 | 
0.4474 | 
0.4485 | 
0.4495 | 
0.4505 | 
0.4515 | 
0.4525 | 
0.4535 | 
0.4545 | 
 
| 1.7 | 
0.4554 | 
0.4564 | 
0.4573 | 
0.4582 | 
0.4591 | 
0.4599 | 
0.4608 | 
0.4616 | 
0.4625 | 
0.4633 | 
 
| 1.8 | 
0.4641 | 
0.4649 | 
0.4656 | 
0.4664 | 
0.4671 | 
0.4678 | 
0.4686 | 
0.4693 | 
0.4699 | 
0.4706 | 
 
| 1.9 | 
0.4713 | 
0.4719 | 
0.4726 | 
0.4732 | 
0.4738 | 
0.4744 | 
0.4750 | 
0.4756 | 
0.4762 | 
0.4767 | 
 
| 2.0 | 
0.4772 | 
0.4778 | 
0.4783 | 
0.4788 | 
0.4793 | 
0.4798 | 
0.4803 | 
0.4808 | 
0.4812 | 
0.4817 | 
 
| 2.1 | 
0.4821 | 
0.4826 | 
0.4830 | 
0.4834 | 
0.4838 | 
0.4842 | 
0.4846 | 
0.4850 | 
0.4854 | 
0.4857 | 
 
| 2.2 | 
0.4861 | 
0.4865 | 
0.4868 | 
0.4871 | 
0.4875 | 
0.4878 | 
0.4881 | 
0.4884 | 
0.4887 | 
0.4890 | 
 
| 2.3 | 
0.4893 | 
0.4896 | 
0.4898 | 
0.4901 | 
0.4904 | 
0.4906 | 
0.4909 | 
0.4911 | 
0.4913 | 
0.4916 | 
 
| 2.4 | 
0.4918 | 
0.4920 | 
0.4922 | 
0.4925 | 
0.4927 | 
0.4929 | 
0.4931 | 
0.4932 | 
0.4934 | 
0.4936 | 
 
| 2.5 | 
0.4938 | 
0.4940 | 
0.4941 | 
0.4943 | 
0.4945 | 
0.4946 | 
0.4948 | 
0.4949 | 
0.4951 | 
0.4952 | 
 
| 2.6 | 
0.4953 | 
0.4955 | 
0.4956 | 
0.4757 | 
0.4959 | 
0.4960 | 
0.4961 | 
0.4962 | 
0.4963 | 
0.4964 | 
 
| 2.7 | 
0.4965 | 
0.4966 | 
0.4967 | 
0.4968 | 
0.4969 | 
0.4970 | 
0.4971 | 
0.4972 | 
0.4973 | 
0.4974 | 
 
| 2.8 | 
0.4974 | 
0.4975 | 
0.4976 | 
0.4977 | 
0.4977 | 
0.4978 | 
0.4979 | 
0.4980 | 
0.4980 | 
0.4981 | 
 
| 2.9 | 
0.4981 | 
0.4982 | 
0.4983 | 
0.4983 | 
0.4984 | 
0.4984 | 
0.4985 | 
0.4985 | 
0.4986 | 
0.4986 | 
 
| 3.0 | 
0.4987 | 
0.4987 | 
0.4987 | 
0.4988 | 
0.4988 | 
0.4989 | 
0.4989 | 
0.4989 | 
0.4990 | 
0.4990 | 
 
 
| 
Source:  Weatherburn, C. E. (1957). Mathematical Statistics. Cambridge University Press. 
 |   
 
 | 
  TABLE A-6   FREQUENCY FACTORS K FOR PEARSON TYPE III DISTRIBUTIONS VERSUS SKEW COEFFICIENT CS AND RETURN PERIOD
T (OR PROBABILITY OF EXCEEDANCE P).    |  
Skew Coeff. Cs | 
Return Period T (y) | 
 
| 1.05 | 
1.11 | 
1.25 | 
2 | 
5 | 
10 | 
25 | 
50 | 
100 | 
200 | 
 
|   | 
Probability of Exceedance (percent) | 
 
| 95 | 
90 | 
80 | 
50 | 
20 | 
10 | 
4 | 
2 | 
1 | 
0.5 | 
 
| 3.0 | 
-0.665 | 
-0.660 | 
-0.636 | 
-0.396 | 
0.420 | 
1.180 | 
2.278 | 
3.152 | 
4.051 | 
4.970 | 
 
| 2.8 | 
-0.711 | 
-0.702 | 
-0.666 | 
-0.384 | 
0.460 | 
1.210 | 
2.275 | 
3.114 | 
3.973 | 
4.847 | 
 
| 2.6 | 
-0.762 | 
-0.747 | 
-0.696 | 
-0.368 | 
0.499 | 
1.238 | 
2.267 | 
3.071 | 
3.889 | 
4.718 | 
 
| 2.4 | 
-0.819 | 
-0.795 | 
-0.725 | 
-0.351 | 
0.537 | 
1.262 | 
2.256 | 
3.023 | 
3.800 | 
4.584 | 
 
| 2.2 | 
-0.882 | 
-0.844 | 
-0.752 | 
-0.330 | 
0.574 | 
1.284 | 
2.240 | 
2.970 | 
3.075 | 
4.444 | 
 
| 2.0 | 
-0.949 | 
-0.895 | 
-0.777 | 
-0.307 | 
0.609 | 
1.302 | 
2.219 | 
2.192 | 
3.605 | 
4.398 | 
 
| 1.8 | 
-1.020 | 
-0.945 | 
-0.799 | 
-0.282 | 
0.643 | 
1.318 | 
2.193 | 
2.848 | 
3.499 | 
4.147 | 
 
| 1.6 | 
-1.093 | 
-0.994 | 
-0.817 | 
-0.254 | 
0.675 | 
1.329 | 
2.163 | 
2.780 | 
3.388 | 
3.990 | 
 
| 1.4 | 
-1.168 | 
-1.041 | 
-0.832 | 
-0.225 | 
0.705 | 
1.337 | 
2.128 | 
2.706 | 
3.271 | 
3.828 | 
 
| 1.2 | 
-1.243 | 
-1.086 | 
-0.844 | 
-0.195 | 
0.732 | 
1.340 | 
2.087 | 
2.626 | 
3.149 | 
3.661 | 
 
| 1.0 | 
-1.317 | 
-1.128 | 
-0.852 | 
-0.164 | 
0.758 | 
1.340 | 
2.043 | 
2.542 | 
3.022 | 
3.489 | 
 
| 0.8 | 
-1.388 | 
-1.166 | 
-0.856 | 
-0.132 | 
0.780 | 
1.336 | 
1.993 | 
2.453 | 
2.891 | 
3.312 | 
 
| 0.6 | 
-1.458 | 
-1.200 | 
-0.857 | 
-0.099 | 
0.800 | 
1.328 | 
1.939 | 
2.359 | 
2.755 | 
3.132 | 
 
| 0.4 | 
-1.524 | 
-1.231 | 
-0.855 | 
-0.066 | 
0.816 | 
1.317 | 
1.880 | 
2.261 | 
2.615 | 
2.949 | 
 
| 0.2 | 
-1.586 | 
-1.258 | 
-0.850 | 
-0.033 | 
0.830 | 
1.301 | 
1.818 | 
2.159 | 
2.472 | 
2.763 | 
 
| 0.0 | 
-1.645 | 
-1.282 | 
-0.842 | 
0.000 | 
0.842 | 
1.282 | 
1.751 | 
2.054 | 
2.326 | 
2.576 | 
 
| -0.2 | 
-1.700 | 
-1.301 | 
-0.830 | 
0.033 | 
0.850 | 
1.258 | 
1.680 | 
1.945 | 
2.178 | 
2.388 | 
 
| -0.4 | 
-1.750 | 
-1.317 | 
-0.816 | 
0.066 | 
0.855 | 
1.231 | 
1.606 | 
1.834 | 
2.029 | 
2.201 | 
 
| -0.6 | 
-1.797 | 
-1.328 | 
-0.800 | 
0.099 | 
0.857 | 
1.200 | 
1.528 | 
1.720 | 
1.880 | 
2.016 | 
 
| -0.8 | 
-1.839 | 
-1.336 | 
-0.780 | 
0.132 | 
0.856 | 
1.166 | 
1.448 | 
1.606 | 
1.733 | 
1.837 | 
 
| -1.0 | 
-1.877 | 
-1.340 | 
-0.758 | 
0.164 | 
0.852 | 
1.128 | 
1.366 | 
1.492 | 
1.588 | 
1.664 | 
 
| -1.2 | 
-1.910 | 
-1.340 | 
-0.732 | 
0.195 | 
0.844 | 
1.086 | 
1.282 | 
1.379 | 
1.449 | 
1.501 | 
 
| -1.4 | 
-1.938 | 
-1.337 | 
-0.705 | 
0.225 | 
0.832 | 
1.041 | 
1.198 | 
1.270 | 
1.318 | 
1.351 | 
 
| -1.6 | 
-1.962 | 
-1.329 | 
-0.675 | 
0.254 | 
0.817 | 
0.994 | 
1.116 | 
1.166 | 
1.197 | 
1.216 | 
 
| -1.8 | 
-1.981 | 
-1.318 | 
-0.643 | 
0.282 | 
0.799 | 
0.945 | 
1.035 | 
1.069 | 
1.087 | 
1.097 | 
 
| -2.0 | 
-1.996 | 
-1.302 | 
-0.609 | 
0.307 | 
0.777 | 
0.895 | 
0.959 | 
0.980 | 
0.990 | 
0.995 | 
 
| -2.2 | 
-2.006 | 
-1.284 | 
-0.574 | 
0.330 | 
0.752 | 
0.844 | 
0.888 | 
0.900 | 
0.905 | 
0.907 | 
 
| -2.4 | 
-2.011 | 
-1.262 | 
-0.537 | 
0.351 | 
0.725 | 
0.795 | 
0.823 | 
0.830 | 
0.832 | 
0.833 | 
 
| -2.6 | 
-2.013 | 
-1.238 | 
-0.499 | 
0.368 | 
0.696 | 
0.747 | 
0.764 | 
0.768 | 
0.769 | 
0.769 | 
 
| -2.8 | 
-2.010 | 
-1.210 | 
-0.460 | 
0.384 | 
0.666 | 
0.702 | 
0.712 | 
0.714 | 
0.714 | 
0.714 | 
 
| -3.0 | 
-2.003 | 
-1.180 | 
-0.420 | 
0.393 | 
0.636 | 
0.660 | 
0.666 | 
0.666 | 
0.667 | 
0.667 | 
 
 
| 
Source:  U.S. Interagency Committe on Water Data, Hydrology Subcommitee (1983). "Guidelines
for Determining Flood Flow Frequency," Bulletin No. 17B, issued 1981, revised 1983. 
 |   
 
 | 
TABLE A-7   OUTLIER FREQUENCY FACTORS Kn FOR LOGPEARSON DISTRIBUTIONS. |  
Record Length (y) | 
Kn | 
Record Length (y) | 
Kn | 
Record Length (y) | 
Kn | 
Record Length (y) | 
Kn | 
 
| 10 | 
2.036 | 
45 | 
2.727 | 
80 | 
2.940 | 
115 | 
3.064 | 
 
| 15 | 
2.247 | 
50 | 
2.768 | 
85 | 
2.961 | 
120 | 
3.078 | 
 
| 20 | 
2.385 | 
55 | 
2.804 | 
90 | 
2.981 | 
125 | 
3.092 | 
 
| 25 | 
2.486 | 
60 | 
2.837 | 
95 | 
3.000 | 
130 | 
3.104 | 
 
| 30 | 
2.563 | 
65 | 
2.866 | 
100 | 
3.017 | 
135 | 
3.116 | 
 
| 35 | 
2.628 | 
70 | 
2.893 | 
105 | 
3.033 | 
140 | 
3.129 | 
 
| 40 | 
2.682 | 
75 | 
2.917 | 
110 | 
3.049 | 
145 | 
3.140 | 
 
 
| 
Source:  U.S. Interagency Committe on Water Data, Hydrology Subcommitee (1983). "Guidelines
for Determining Flood Flow Frequency," Bulletin No. 17B, issued 1981, revised 1983. 
 |   
 
 | 
TABLE A-8   MEAN ȳn AND STANDARD DEVIATION σn OF GUMBEL VARIATE (y) VERSUS RECORD LENGTH n. |  
| n | 
yn | 
σn | 
n | 
yn | 
σn | 
n | 
yn | 
σn | 
 
| 8 | 
0.4843 | 
0.9043 | 
35 | 
0.5403 | 
1.1285 | 
64 | 
0.5533 | 
1.1793 | 
 
| 9 | 
0.4902 | 
0.9288 | 
36 | 
0.5410 | 
1.1313 | 
66 | 
0.5538 | 
1.1814 | 
 
| 10 | 
0.4952 | 
0.9497 | 
37 | 
0.5418 | 
1.1339 | 
68 | 
0.5543 | 
1.1834 | 
 
| 11 | 
0.4996 | 
0.9676 | 
38 | 
0.5424 | 
1.1363 | 
70 | 
0.5548 | 
1.1854 | 
 
| 12 | 
0.5035 | 
0.9833 | 
39 | 
0.5430 | 
1.1388 | 
72 | 
0.5552 | 
1.1873 | 
 
| 13 | 
0.5070 | 
0.9972 | 
40 | 
0.5436 | 
1.1413 | 
74 | 
0.5557 | 
1.1890 | 
 
| 14 | 
0.5100 | 
1.0095 | 
41 | 
0.5442 | 
1.1436 | 
76 | 
0.5561 | 
1.1906 | 
 
| 15 | 
0.5128 | 
1.0206 | 
42 | 
0.5448 | 
1.1458 | 
78 | 
0.5565 | 
1.1923 | 
 
| 16 | 
0.5157 | 
1.0316 | 
43 | 
0.5453 | 
1.1480 | 
80 | 
0.5569 | 
1.1938 | 
 
| 17 | 
0.5181 | 
1.0411 | 
44 | 
0.5458 | 
1.1499 | 
82 | 
0.5572 | 
1.1953 | 
 
| 18 | 
0.5202 | 
1.0493 | 
45 | 
0.5463 | 
1.1519 | 
84 | 
0.5576 | 
1.1967 | 
 
| 19 | 
0.5220 | 
1.0566 | 
46 | 
0.5468 | 
1.1538 | 
86 | 
0.5580 | 
1.1980 | 
 
| 20 | 
0.5236 | 
1.0628 | 
47 | 
0.5473 | 
1.1557 | 
88 | 
0.5583 | 
1.1994 | 
 
| 21 | 
0.5252 | 
1.0696 | 
48 | 
0.5477 | 
1.1574 | 
90 | 
0.5586 | 
1.2007 | 
 
| 22 | 
0.5268 | 
1.0754 | 
49 | 
0.5481 | 
1.1590 | 
92 | 
0.5589 | 
1.2020 | 
 
| 23 | 
0.5283 | 
1.0811 | 
50 | 
0.5485 | 
1.1607 | 
94 | 
0.5592 | 
1.2032 | 
 
| 24 | 
0.5296 | 
1.0864 | 
51 | 
0.5489 | 
1.1623 | 
96 | 
0.5595 | 
1.2044 | 
 
| 25 | 
0.5309 | 
1.0915 | 
52 | 
0.5493 | 
1.1638 | 
98 | 
0.5598 | 
1.2055 | 
 
| 26 | 
0.5320 | 
1.0961 | 
53 | 
0.5497 | 
1.1653 | 
100 | 
0.5600 | 
1.2065 | 
 
| 27 | 
0.5332 | 
1.1004 | 
54 | 
0.5501 | 
1.1667 | 
150 | 
0.5646 | 
1.2253 | 
 
| 28 | 
0.5343 | 
1.047 | 
55 | 
0.5504 | 
1.1681 | 
200 | 
0.5672 | 
1.2360 | 
 
| 29 | 
0.5353 | 
1.1086 | 
56 | 
0.5508 | 
1.1696 | 
250 | 
0.5688 | 
1.2429 | 
 
| 30 | 
0.5362 | 
1.1124 | 
57 | 
0.5511 | 
1.1708 | 
300 | 
0.5699 | 
1.2479 | 
 
| 31 | 
0.5371 | 
1.1159 | 
58 | 
0.5515 | 
1.1721 | 
400 | 
0.5714 | 
1.2545 | 
 
| 32 | 
0.5380 | 
1.1193 | 
59 | 
0.5518 | 
1.1734 | 
500 | 
0.5724 | 
1.2588 | 
 
| 33 | 
0.5388 | 
0.1226 | 
60 | 
0.5521 | 
1.1747 | 
750 | 
0.5738 | 
1.2651 | 
 
| 34 | 
0.5396 | 
1.1255 | 
62 | 
0.5527 | 
1.1770 | 
1000 | 
0.5745 | 
1.2685 | 
 
 
| 
Source:  Gumbel, E. J. (1958). Statistics of Extremes. Irvington, New York: Columbia University Press. 
 
 |   
 
 | 
TABLE A-9   NRCS 24-HR RAINFALL TABLES (AT HALF-HOUR INCREMENTS). |  
Time (h) | 
Fraction of 24-h rainfall depth | 
 
| Type I | 
Type IA | 
Type II | 
Type III | 
 
| 0.0 | 
0.00000 | 
0.00000 | 
0.00000 | 
0.00000 | 
 
| 0.5 | 
0.00871 | 
0.01000 | 
0.00513 | 
0.00500 | 
 
| 1.0 | 
0.01745 | 
0.02000 | 
0.01050 | 
0.01000 | 
 
| 1.5 | 
0.02621 | 
0.03500 | 
0.01613 | 
0.01500 | 
 
| 2.0 | 
0.03500 | 
0.05000 | 
0.02200 | 
0.02000 | 
 
| 2.5 | 
0.04416 | 
0.06600 | 
0.02813 | 
0.02519 | 
 
| 3.0 | 
0.05405 | 
0.08200 | 
0.03450 | 
0.03075 | 
 
| 3.5 | 
0.06466 | 
0.09800 | 
0.04113 | 
0.03669 | 
 
| 4.0 | 
0.07600 | 
0.11600 | 
0.04800 | 
0.04300 | 
 
| 4.5 | 
0.08784 | 
0.13500 | 
0.05525 | 
0.04969 | 
 
| 5.0 | 
0.09995 | 
0.15600 | 
0.06300 | 
0.05675 | 
 
| 5.5 | 
0.11234 | 
0.18000 | 
0.07125 | 
0.06419 | 
 
| 6.0 | 
0.12500 | 
0.20600 | 
0.0800 | 
0.07200 | 
 
| 6.5 | 
0.13915 | 
0.23700 | 
0.08925 | 
0.08063 | 
 
| 7.0 | 
0.15600 | 
0.26800 | 
0.09900 | 
0.09050 | 
 
| 7.5 | 
0.17460 | 
0.31000 | 
0.10925 | 
0.10163 | 
 
| 8.0 | 
0.19400 | 
0.42500 | 
0.12000 | 
0.11400 | 
 
| 8.5 | 
0.21900 | 
0.48000 | 
0.13225 | 
0.12844 | 
 
| 9.0 | 
0.25400 | 
0.52000 | 
0.14700 | 
0.14575 | 
 
| 9.5 | 
0.30300 | 
0.55000 | 
0.16300 | 
0.16594 | 
 
| 10.0 | 
0.51500 | 
0.57700 | 
0.18100 | 
0.18900 | 
 
| 10.5 | 
0.58300 | 
0.60100 | 
0.20400 | 
0.21650 | 
 
| 11.0 | 
0.62300 | 
0.62400 | 
0.23500 | 
0.25000 | 
 
| 11.5 | 
0.65550 | 
0.64500 | 
0.28300 | 
0.29800 | 
 
| 12.0 | 
0.68400 | 
0.66400 | 
0.66300 | 
0.50000 | 
 
| 12.5 | 
0.70925 | 
0.68300 | 
0.73500 | 
0.70200 | 
 
| 13.0 | 
0.73200 | 
0.70100 | 
0.77200 | 
0.75000 | 
 
| 13.5 | 
0.75225 | 
0.71900 | 
0.79900 | 
0.78350 | 
 
| 14.0 | 
0.77000 | 
0.73600 | 
0.82000 | 
0.81100 | 
 
| 14.5 | 
0.78625 | 
0.75281 | 
0.83763 | 
0.83406 | 
 
| 15.0 | 
0.80200 | 
0.76924 | 
0.85350 | 
0.85425 | 
 
| 15.5 | 
0.81725 | 
0.78529 | 
0.86763 | 
0.87156 | 
 
| 16.0 | 
0.83200 | 
0.80096 | 
0.88000 | 
0.88600 | 
 
| 16.5 | 
0.84625 | 
0.81625 | 
0.89119 | 
0.89838 | 
 
| 17.0 | 
0.86000 | 
0.83116 | 
0.90175 | 
0.90950 | 
 
| 17.5 | 
0.87325 | 
0.84569 | 
0.91169 | 
0.91938 | 
 
| 18.0 | 
0.88600 | 
0.85984 | 
0.92100 | 
0.92800 | 
 
| 18.5 | 
0.89825 | 
0.87361 | 
0.92969 | 
0.93581 | 
 
| 19.0 | 
0.91000 | 
0.88700 | 
0.93775 | 
0.94325 | 
 
| 19.5 | 
0.92125 | 
0.90001 | 
0.94519 | 
0.95031 | 
 
| 20.0 | 
0.93200 | 
0.91264 | 
0.95200 | 
0.95700 | 
 
| 20.5 | 
0.94225 | 
0.92489 | 
0.95844 | 
0.96336 | 
 
| 21.0 | 
0.95200 | 
0.93676 | 
0.96475 | 
0.96944 | 
 
| 21.5 | 
0.96125 | 
0.94825 | 
0.97094 | 
0.97523 | 
 
| 22.0 | 
0.97000 | 
0.95936 | 
0.97700 | 
0.98075 | 
 
| 22.5 | 
0.97825 | 
0.97009 | 
0.98294 | 
0.98598 | 
 
| 23.0 | 
0.98600 | 
0.98044 | 
0.98875 | 
0.99094 | 
 
| 23.5 | 
0.99325 | 
0.99041 | 
0.99444 | 
0.99561 | 
 
| 24.0 | 
1.00000 | 
1.00000 | 
1.00000 | 
1.00000 | 
 
 
| 
Source: Roger G. Cronshey, USDA Natural Resources Conservation Service, Engineering Division, Washington, D.C., June 1988.
 |   
 
 | 
TABLE A-10   STANDARD NRCS DIMENSIONLESS TEMPORAL RAINFALL DISTRIBUTION FOR EMERGENCY SPILLWAY AND FREEBOARD-POOL DESIGN. |  
| Fraction of storm duration | 
Fraction of storm depth | 
Fraction of storm duration | 
Fraction of storm depth  | 
 
| 0.00 | 
0.0000 | 
  | 
  | 
 
| 0.02 | 
0.0080 | 
0.52 | 
0.7240 | 
 
| 0.04 | 
0.0162 | 
0.54 | 
0.7420 | 
 
| 0.06 | 
0.0246 | 
0.56 | 
0.7590 | 
 
| 0.08 | 
0.0333 | 
0.58 | 
0.7750 | 
 
| 0.10 | 
0.0425 | 
0.60 | 
0.7900 | 
 
| 0.12 | 
0.0524 | 
0.62 | 
0.8043 | 
 
| 0.14 | 
0.0630 | 
0.64 | 
0.8180 | 
 
| 0.16 | 
0.0743 | 
0.66 | 
0.8312 | 
 
| 0.18 | 
0.0863 | 
0.68 | 
0.8439 | 
 
| 0.20 | 
0.0990 | 
0.70 | 
0.8561 | 
 
| 0.22 | 
0.1124 | 
0.72 | 
0.8678 | 
 
| 0.24 | 
0.1265 | 
0.74 | 
0.8790 | 
 
| 0.26 | 
0.1420 | 
0.76 | 
0.8898 | 
 
| 0.28 | 
0.1595 | 
0.78 | 
0.9002 | 
 
| 0.30 | 
0.1800 | 
0.80 | 
0.9103 | 
 
| 0.32 | 
0.2050 | 
0.82 | 
0.9201 | 
 
| 0.34 | 
0.2550 | 
0.84 | 
0.9297 | 
 
| 0.36 | 
0.3450 | 
0.86 | 
0.9391 | 
 
| 0.38 | 
0.4370 | 
0.88 | 
0.9483 | 
 
| 0.40 | 
0.5300 | 
0.90 | 
0.9573 | 
 
| 0.42 | 
0.6030 | 
0.92 | 
0.9661 | 
 
| 0.44 | 
0.6330 | 
0.94 | 
0.9747 | 
 
| 0.46 | 
0.6600 | 
0.96 | 
0.9832 | 
 
| 0.48 | 
0.6840 | 
0.98 | 
0.9916 | 
 
| 0.50 | 
0.7050 | 
1.00 | 
1.0000 | 
 
 
| 
Source: USDA Natural Resources Conservation Service. (1983). "Computer Program for Project Formulation: Hydrology,"
Tecnical Release No. 20  (TR-20), Engineering Division, Washington, D.C., May.
 |   
 |