High Plains Unit: That portion of Kansas west of federal highway US-283

Low Plains Early Zone: That part of Kansas bounded by a line from the federal highway US-283 and state highway US-96 junction, then east on federal highway US-96 to its junction with federal highway US-183, then north on federal highway US-183 to its junction with federal highway US-24, then east on federal highway US-24 to its junction with federal highway US-281, then north on federal highway US-281 to its junction with federal highway US-36, then east on federal highway US-36 to its junction with state highway K-199, then south on state highway K-199 to its junction with Republic County 30^th Road, then south on Republic County 30^th Road to its junction with state highway K-148, then east on state highway K-148 to its junction with Republic County 50^th Road,  then south on Republic County 50^th Road to its junction with Cloud County 40^th Road, then south on Cloud County 40^th Road to its junction with state highway K-9, then west on state highway K-9 to its junction with federal highway US-24, then west on federal highway US-24 to its junction with federal highway US-181, then south on federal highway US-181 to its junction with state highway K-18, then west on state highway K-18 to its junction with federal highway US-281, then south on federal highway US-281 to its junction with state highway K-4, then east on state highway K-4 to its junction with interstate highway I-135, then south on interstate highway I–135 to its junction with state highway K-61, then southwest on state highway K-61 to its junction with McPherson County 14^th Avenue, then south on McPherson County 14^th Avenue to its junction with McPherson County Arapaho Rd, then west on McPherson County Arapaho Rd to its junction with state highway K-61, then southwest on state highway K-61 to its junction with state highway K-96, then northwest on state highway K-96 to its junction with federal highway US-56, then southwest on federal highway US-56 to its junction with state highway K-19, then east on state highway K-19 to its junction with federal highway US-281, then south on federal highway US-281 to its junction with federal highway US-54, then west on federal highway US-54 to its junction with federal highway US-183, then north on federal highway US-183 to its junction with federal highway US-56, then southwest on federal highway US-56 to its junction with North Main Street in Spearville, Kansas, then south on  North Main Street to Davis Street in Spearville, Kansas, then east on Davis Street to Ford County Road 126 (South Stafford Street in Spearville, Kansas), then south on Ford County Road 126 to Garnett Road, then east on Garnett Road to Ford County Road 126, then south on Ford County Road 126 to Ford Spearville Road, then west on Ford Spearville Road to its junction with federal highway US-400, then northwest on federal highway US-400 to its junction with federal highway US-283, and then north on federal highway US-283 to its junction with federal highway US-96.

Low Plains Late Zone: That part of Kansas bounded by a line from the federal highway US-283 and federal highway US-96 junction, then north on federal highway US-283 to the Kansas-Nebraska state line, then east along the Kansas-Nebraska state line to its junction with the Kansas-Missouri state line, then southeast along the Kansas-Missouri state line to its junction with state highway K-68, then west on state highway K-68 to its junction with interstate highway I-35, then southwest on interstate highway I-35 to its junction with Butler County NE 150^th Street, then west on Butler County NE 150^th Street to its junction with federal highway US-77, then south on federal highway US-77 to its junction with the Kansas-Oklahoma state line, then west along the Kansas-Oklahoma state line to its junction with federal highway US-283, then north on federal highway US-283 to its junction with federal highway US-400, then east on federal highway US-400 to its junction with Ford Spearville Road, then east on Ford Spearville Road to Ford County Road 126, then north on Ford County Road 126 to Garnett Road, then west on Garnett Road to Ford County Road 126, then north on Ford County Road 126 (South Stafford Street in Spearville, Kansas) to Davis Street in Spearville, Kansas, then west on Davis Street to North Main Street in Spearville, Kansas, then north on  North Main Street to its junction with federal highway US-56, then east on federal highway US-56 to its junction with federal highway US-183, then south on federal highway US-183 to its junction with federal highway US-54, then east on federal highway US-54 to its junction with federal highway US-281, then north on federal highway US-281 to its junction with state highway K-19, then west on state highway K-19 to its junction with federal highway US-56, then east on federal highway US-56 to its junction with state highway K-96, then southeast on state highway K-96 to its junction with state highway K-61, then northeast on state highway K-61 to its junction with McPherson County Arapaho Road, then east on McPherson County Arapaho Road to its junction with McPherson County 14^th Avenue, then north on McPherson County 14^th Avenue to its junction with state highway K-61, then east on state highway K-61 to its junction with interstate highway I-135, then north on interstate highway I-135 to its junction with state highway K-4, then west on state highway K-4 to its junction with federal highway US-281, then north on federal highway US-281 to its junction with state highway K-18, then east on state highway K-18 to its junction with federal highway US-181, then north on federal highway US-181 to its junction with federal highway US-24, then east on federal highway US-24 to its junction with state highway K-9, then east on state highway K-9 to its junction with Cloud County 40^th Road, then north on Cloud County 40^th Road to its junction with Republic County 50^th Road, then north on Republic County 50^th Road to its junction with state highway K-148, then west on state highway K-1­48 to its junction with Republic County 30^th Road, then north on Republic County 30^th Road to its junction with state highway K-199, then north on state highway K-199 to its junction with federal highway US-36, then west on federal highway US-36 to its junction with federal highway US-281, then south on federal highway US-281 to its junction with federal highway US-24, then west on federal highway US-24 to its junction with federal highway US-183, then south on federal highway US-183 to its junction with federal highway US-96, and then west on federal highway US-96 to its junction with federal highway US-283.

Low Plains Southeast Zone: That part of Kansas bounded by a line from the Kansas-Missouri state line west on state highway K-68 to its junction with interstate highway I-35, then southwest on interstate highway I-35 to its junction with Butler County NE 150^th  Street, then west on Butler County NE 150^th Street to its junction with federal highway US-77, then south on federal highway US-77 to the Kansas-Oklahoma State line, then east along the Kansas–Oklahoma state line to its junction with the Kansas-Missouri state line, and then north along the Kansas-Missouri state line to its junction with state highway K-68.