Weather Data - Hours available for evaporative cooling:


 Location:  Houston, TX - Ellington AFB    Elev: 40 Feet     Lat:  29 / 37 N Long: 95/ 10 W

Mean Frequency of occurrence of Dry Bulb Temperature with Mean Coincident Wet Bulb Temperature for each Dry Bulb Temperature Range:

ASHRAE  design Dry Bulb and Mean Coincident Wet Bulb:
   1% Scale:    2.5% Scale:    5% Scale:            Design Wet Bulb:
Db       Wb       Db      Wb        Db      Wb           1%     2.5%     5%
96        77        94        77        92        77            80        79       79

Average number of hours within each temperature range and discharge temp. (see notes):

January - April Weather Data

Temp Range: Deg (f) January February March April Total
Low High Mean Hours Wb Tout Hours Wb Tout Hours Wb Tout Hours Wb Tout  
115 120 117.5                          
110 114 112                          
105 109 107                          
100 104 102                          
95 99 97                          
90 94 92                          
85 89 87                   6 67 68 6
80 84 82             7 65 65.9 44 65 65.9 51
75 79 77 2 65 65.6 5 65 65.6 18 63 63.7 65 63 63.7 90
70 74 72 10 64 64.4 20 61 61.6 43 61 61.6 97 62 62.5 170
65 69 67 39 61 61.3 44 59 59.7 81 58 58.5 129 59 59.4 293
60 64 62 59 57 57.3 75 55 55.4 98 54 54.4 123 56 56.3 355
55 59 57 72 52 52.3 93 51 51.3 114 51 51.3 88 51 51.3 367
50 54 52 87 47 47.3 84 46 46.3 106 46 46.3 69 47 47.3 346
45 49 47 105 43 43.2 95 42 42.3 85 42 42.3 50 43 43.2 335
40 44 42 101 38 38.2 86 38 38.2 85 38 38.2 30 39 39.2 202
35 39 37 105 34 34.2 70 34 34.2 58 34 34.2 16 35 35.1 249
30 34 32 73 30 30.1 48 30 30.1 36 30 30.1 4 31 31.1 161
Total hours Temp out over 40(f) 374   416   552   671 Total hours for this period 2013

Note: 1.  Db = Dry Bulb(f) temperature, Wb = Mean coincident wet bulb temp (f).  Tout = Discharge Temperature (f).   Only hours where discharge temp is over 400(f) is included in total hours available for evaporative cooling.

May - August Weather Data

Temp Range: Deg (f) May June July August Total
Low High Mean Hours Wb Tout Hours Wb Tout Hours Wb Tout Hours Wb Tout  
115 120 117.5                          
110 114 112                          
105 109 107                          
100 104 102       1 75 76.4       1 77 79 2
95 99 97 2 71 72.3 11 74 75.2 18 79 79.9 17 78 79.7 48
90 94 92 19 70 71.1 54 74 74.9 106 78 78.7 97 78 79.5 276
85 89 87 61 69 69.9 95 72 72.8 142 77 77.5 131 77 78.3 429
80 84 82 92 68 68.7 120 71 71.6 153 76 76.3 155 76 77.1 520
75 79 77 106 67 67.5 153 70 70.4 250 74 74.2 264 74 74.9 773
70 74 72 139 65 65.4 173 68 68.2 68 70 70.1 72 71 71.8 452
65 69 67 155 63 63.5 78 64 64.4 5 65 65.1 7 65 65.9 245
60 64 62 85 58 58.2 25 59 59.2 1 59 59.2 1 59 59.9 112
55 59 57 47 54 54.2 8 56 56.1             55
50 54 52 21 49 49.2 2 50 50.1             23
45 49 47 13 45 45.1                   13
40 44 42 5 41 41.1                   5
35 39 37                          
30 34 32                          
Total hours Temp out over 40(f) 740   720   743   745 Total hours for this period 2948

September - December Weather Data

Temp Range: Deg (f) September October November December Total
Low High Mean Hours Wb Tout Hours Wb Tout Hours Wb Tout Hours Wb Tout  
115 120 117.5                          
110 114 112                          
105 109 107                          
100 104 102                          
95 99 97 2 77 78                   2
90 94 92 31 77 77.8 2 77 77.8             33
85 89 87 109 76 76.6 36 74 74.7 2 71 71.8       147
80 84 82 135 75 75.4 79 72 72.5 21 71 71.6 1 69 69.7 236
75 79 77 221 73 73.2 125 69 69.4 62 69 69.4 20 68 68.5 428
70 74 72 143 70 70.1 154 67 67.3 96 66 66.3 53 66 66.3 446
65 69 67 55 64 64.2 134 63 63.2 125 63 63.2 87 63 63.2 401
60 64 62 18 59 59.2 96 58 58.2 109 58 58.2 112 58 58.2 335
55 59 57 6 59 58.9 63 53 53.4 91 53 53.2 114 53 53.2 274
50 54 52       38 49 49.2 89 48 48.2 109 48 48.2 236
45 49 47       13 45 45.1 65 44 44.2 108 44 44.2 186
40 44 42       2 40 40.1 36 39 39.2 72 39 39.2 110
35 39 37       1 37 37.1 15 34 34.2 44 35 35.1 60
30 34 32             5 30 30.1 19 30 30.1 24
Total hours Temp out over 40(f) 720   740   660   604 Total hours for this period 2724
Total hours available for evaporative cooling 7685

Data published by Premier Industries, Inc., in part from data contained in EcoDyne's Weather Data Handbook no longer in print.  Premier Industries, Inc., provides these data for informational use only.  All reasonable precautions have been taken to maintain integrity in these data however  Premier Industries will not be responsible for it's accuracy.  Any responsibility for the use of this information shall be borne by the user.