Filed Under: 
Environment

 

Climatic Regions of Texas

 

The following table shows the extent of drought by major region (abbreviated) by listing the percent of normal precipitation. Drought here is arbitrarily defined as when there is less than 75 percent of normal precipitation. There was no drought in any region in the years not listed. Note that in 2011, as well as 1917 and 1956, all the regions were in drought. Source: Office of State Climatologist, Texas A&M University.

Year HP LRP NC ET TP EP SC UC ST LV
2014      73              
2013 74                  
2012 68 74             74 82
2011 40 43 65 63 29 49 47 47 46 52
2010     70            
2008           66 61      
2006           66        
2005     68 66            72
2003 65 71                
2001         56          
2000         74          67
1999     73     67 69 69    
1998   69      71          
1996             71   60 70
1994          68          
1990                    73
1989            72      66  64
1988            67  62  67  68  
1970  65  63        72        
1964  74        69          63
1963      63  68    65  61  73    
1962            68      67  65
1956  51  57  61  68  44  43  55  62  53  53
1954  70  71  68  73    50  50  57  71  
1953  69        49  73        
1952  68  66      73        56  70
1951          61  53        
1950              68    74  64
1948      73  74  62    71   67    
1943      72              
1939              69      72
1937                  72  
1934  66        46  69        
1933  72        62  68        
1927                74    74
1925      72        72      
1924      73  73    71    72    
1922          68          
1921          72          73
1920                    71
1917  58  50  63  59  44  46  42  50  32  48
1916    73    74  70    73  69    
1911                    70
1910  59  59  64  69  43  65  69  74  59  
1909      72  68  67  74  70      
1907                    65
1902                  65  73
1901    71  70      60  62  70  44  
1898                  69  51
1897              73    72  
1894          68          
1893      67  70    49  56  64  53  59
1892          68      73    
Year HP LRP NC ET TP EP SC UP ST LV

Drought has proven to be difficult to define and there is no universally accepted definition. The most commonly used drought definitions are based on meteorological, agricultural, hydrological and socioeconomic effects. (These definitions are from the New Mexico Drought Planning Team website.)

Meteorological drought is often defined by a period of substantially diminished precipitation duration and/or intensity. The commonly used definition of meteorological drought is an interval of time, generally on the order of months or years, during which the actual moisture supply at a given place consistently falls below the climatically appropriate moisture supply.

Agricultural drought occurs when there is inadequate soil moisture to meet the needs of a particular crop at a particular time. Agricultural drought usually occurs after or during meteorological drought but before hydrological drought and can also affect livestock and other dry-land agricultural operations.

Hydrological drought refers to deficiencies in surface and subsurface water supplies. It is measured as streamflow and as lake, reservoir and groundwater levels. There is usually a delay between lack of rain and less measurable water in streams, lakes and reservoirs. Therefore, hydrological measurements tend to lag other drought indicators.

Socioeconomic drought occurs when physical water shortages start to affect the health, well-being, and quality of life of the people, or when the drought starts to affect the supply and demand of an economic product.