OKLAHOMA · TULSA COUNTY JURISDICTION
Green Country Builds Against the Tornado Alley Wind
On the Arkansas River in northeastern Oklahoma, Tulsa sits where Gulf moisture meets dry plains air. Design every roof and wall to the ASCE 7-22 maps the state code adopts.
WHY THE NUMBER RUNS HIGH
The Plains Convective Belt Sets Tulsa's Base Speed
Tulsa's 110–120 mph map value is a synoptic design speed, not a tornado strike rating. Exact mph varies by site across the county.
Straight-Line Storm Winds
Spring squall lines and derechos push damaging gusts across the metro every season.
SYNOPTIC EVENTSTornado Alley Position
Green Country lies in the corridor's eastern reach; ASCE 7-22 Ch 32 adds qualitative tornado provisions for select structures.
CH 32 QUALITATIVERiver-Valley Terrain
The Arkansas River corridor and open prairie edges shift exposure between dense midtown and breezy outskirts.
EXPOSURE B / CHail-Driven Envelopes
Tulsa is among the most hail-struck metros, so roof systems carry both uplift and impact duty.
ENVELOPE LOADSExposure read for Tulsa. Dense midtown, downtown, Cherry Street and Brookside generally read Exposure B. Open ground south of the Creek Turnpike and developing edges toward Owasso and Broken Arrow often shift to Exposure C, which raises pressures. Confirm per ASCE 7-22 §26.7 for each site.
PERMIT-READY CHECKLIST
Clearing a Tulsa Plan Review on Wind Loads
Six inputs your calculation set needs before the City of Tulsa or county inspector signs off.
Basic Wind Speed
Pull V from the ASCE 7-22 map for the exact Tulsa County site; expect the 110–120 mph band for Risk II.
STEP 1Risk Category
Classify per Table 1.5-1; a higher category reads a longer-return-period map and a higher speed.
STEP 2Exposure Category
Decide B or C from upwind terrain in every direction under §26.7 — it swings pressure hard.
STEP 3Topographic Kzt
Flat river-valley sites stay Kzt = 1.0; isolated bluffs or ridges raise it near the crest only.
STEP 4C&C + MWFRS
Generate component-and-cladding and main-frame pressures with Kd = 0.85 and G = 0.85 for rigid buildings.
STEP 5PE-Sealed Report
Submit Oklahoma-licensed, sealed calculations for commercial and complex work in Green Country.
STEP 6MAP SELECTION BY USE
One Site, Four Maps Under ASCE 7-22
Risk category never multiplies the speed — it sends you to a different return-period map. The mph below stay within Tulsa's mapped band; verify each from the map.
| Risk Category | Map / Return Period | Typical Tulsa Use |
|---|---|---|
| I | 300-year MRI (lowest) | Minor ag and storage near the county edge |
| II | 700-year MRI · 110–120 mph | Homes, retail, offices, standard occupancy |
| III | 1,700-year MRI (higher) | Schools, large assembly, key utilities |
| IV | 3,000-year MRI (highest) | Hospitals, fire/police, emergency shelters |
Tulsa versus Oklahoma City. Both share the Oklahoma UBC and Tornado Alley exposure, but Tulsa's design is shaped by the Arkansas River corridor of Green Country and its dense Art Deco downtown core, while OKC sits on the central plains farther west. Read each city from its own mapped coordinates.
ACROSS OKLAHOMA
Compare Tulsa With the Wider Sooner Map
Jump to the statewide rules and the nearest metro to cross-check your wind inputs.
Oklahoma City
Compare the central-plains metro's wind design to Tulsa's river-valley reads.
SISTER CITYOklahoma Statewide
The adopted code edition, amendments and map basis for the whole state.
STATE PAGEAll State Requirements
Browse adopted ASCE 7 editions and wind rules state by state.
DIRECTORYOfficial Tulsa permit desks. City of Tulsa Building Inspection · Tulsa County Building Inspection · Oklahoma PE Licensing Board · Tulsa Preservation Commission
RUN THE NUMBERS
Calculate Tulsa Wind Loads to ASCE 7-22
Drop in a Tulsa County address and get site-specific velocity, exposure, C&C and MWFRS pressures in a PE-ready report.