---
title: UpdraftForcing
emoji: 🌪️
colorFrom: blue
colorTo: gray
sdk: docker
pinned: false
---

# Updraft Forcing

A kinematic-diagnostic model for examining how environmental wind shear and mesocyclone intensity drive perturbation pressure and vertical accelerations in convective storms.

Configure a Weisman-Klemp analytic sounding and drag the hodograph to set the wind profile, then explore:

- **Skew-T log-P diagram** with parcel trace, CAPE/CIN shading, and meteorological wind barbs
- **Perturbation pressure** decomposed into linear (shear interaction), nonlinear spin, nonlinear splat, and buoyancy terms (Trapp 2013)
- **Vertical velocity** diagnosed from a 1-D pseudoadiabatic parcel model with overshooting top
- **CAPE, CIN, LCL, LFC, EL** from the analytic sounding
- **SRH** (0–2 km, 2–5 km) and **Updraft Helicity** relative to the Bunkers right-mover storm motion
- **Prescribed mesocyclone ζ(z)** driving the nonlinear spin pressure term and updraft helicity

Plan views and vertical cross-sections are available for all 3-D fields. Pressure perturbations are solved via a 2-D FFT + tridiagonal Poisson solver on a 100 × 100 × 161 grid (Δ = 100 m).