Chase geography
Great Plains geography for chasers
Chasers who think the Plains are flat get surprised. Here is the actual geography — canyons, hills, breaks — that affects chase strategy.
Texas Panhandle
Caprock Escarpment
Rise from Rolling Plains to High Plains. 200-1000 ft cliff. Affects storm behavior.
Palo Duro Canyon
Second largest canyon in US. Complex terrain.
Llano Estacado
Flat mesa. High Plains chasing.
Rita Blanca National Grassland
Wide open country.
Fuel spacing
Very sparse in Panhandle.
Oklahoma
Oklahoma Panhandle
Similar to Texas Panhandle.
Wichita Mountains
Small range in SW. Terrain complexity.
Central OK Plains
Classic chase terrain.
Arbuckle Mountains
S OK. Rare terrain feature.
Ouachita Mountains
SE OK. Not chase territory.
Red River
TX-OK border. Not usually chase-relevant.
Kansas
Flint Hills
Eastern KS. Grassland hills. Chase-friendly.
Smoky Hills
North-central KS.
Cross Timbers
SE KS. Oak-dominated.
Chautauqua Hills
SE KS.
Great Bend
North-central KS turning point.
High Plains west
Western KS very high.
Cimarron River
Western KS.
Nebraska
Sandhills
Northern NE. Grass-covered dune country. Sparse population.
Loess Hills
Missouri Valley edge.
Pine Ridge
NW NE.
North Platte Valley
Elevation change.
Republican River
Southern NE.
Moisture note
Rain shadow of Rockies affects moisture.
South Dakota
Black Hills
Western SD. Not chase terrain.
Badlands
Western SD. Complex terrain.
Missouri River corridor
Divides state.
James River valley
Chase-friendly.
Big Sioux River
East.
North Dakota
Missouri Plateau
Central-western ND.
Turtle Mountains
Northern border.
Red River Valley
Eastern flat.
Devils Lake
Basin.
International boundary
Canada complications.
Colorado
Front Range
Rockies edge. Landspout country.
Eastern Plains
Chase territory.
Palmer Divide
Storm splitter feature.
Arkansas River valley
Southern CO.
Denver metro complications
Population + terrain.
High altitude
Affects storm behavior.
Iowa
Rolling terrain
Not flat.
Missouri River valley
West.
Mississippi valley
East.
Des Moines Lobe
Central prairie.
Chase note
Chase-friendly but tree cover.
Missouri
Ozark Plateau
Southern MO. Not chase territory.
Missouri River valley
Central.
Mississippi valley
East.
Bootheel
SE MO. Delta country.
Chase note
Rolling terrain complicates chasing.
Illinois and Indiana
Central Illinois Plain
Chase-adjacent.
Illinois River valley
Terrain.
Indiana Till Plain
Rolling.
Wabash Valley
IN-IL border.
Grand Prairie area
Historic prairie.
The road grid reality
- Section-line roads every mile in most Plains counties.
- Gravel becomes mud fast.
- US highways provide fast E-W passage.
- US-83 north-south corridor through Plains.
- US-54 across Panhandle.
- US-56 diagonal.
- I-40, I-70, I-80 for interstate access.
- Rural US highways for chase.
- Section-line roads for pivots.
- Farm-to-market roads for detail work.
The elevation gradient
East to west
Rising 3000+ ft across the Plains.
Eastern Nebraska
1000 ft elevation.
Western Nebraska
5000+ ft.
Denver
5280 ft.
Amarillo
3600 ft.
Wichita
1300 ft.
Oklahoma City
1200 ft.
Elevation impact 1
Higher = drier atmosphere = higher LCL.
Elevation impact 2
Higher = colder cloud tops.
Elevation impact 3
Higher = often better hail growth.
The moisture gradient
East
Wetter. Higher dewpoints.
West
Drier. Lower dewpoints.
The dryline
Boundary between moist and dry.
Dryline motion
Moves east during afternoon.
Chase target
Dryline + convergence.
Gulf moisture
Gulf of Mexico feeds moisture northward.
LLJ
Low-level jet delivers overnight.
The specific chase-day geography
Sunlit slopes
Warm faster. Create local convergence.
River valleys
Cooler. Sometimes disorganize storms.
Ridge lines
Wind acceleration.
Escarpments
Force convection.
Highways
Access + escape.
Grid roads
Section-line pivots.
Population centers
Avoid direct hits when possible.
The specific chase corridor
I-40 east-west
Amarillo to OKC to Little Rock.
US-54
Diagonal Panhandle.
US-83 north-south
Nebraska to Texas.
US-183
Nebraska to Texas.
US-283
Kansas to Texas.
I-70 east-west
Denver to Kansas.
US-56
Diagonal.
The unexpected terrain features
Sandhills
NE Sandhills disrupt chase logistics.
Cross Timbers
Wooded strip Oklahoma to Texas.
Wichita Mountains
Small OK range.
Ozark foothills
MO edge.
Ouachita Mountains
Not chase territory.
Coteau des Prairies
MN-SD ridge.
Loess Hills
IA-NE Missouri valley.