Can a cloud form, then stop climbing?: sources & model

Step through real satellite observations, release an air parcel into a measured atmosphere, and discover why moisture, lifting and the surrounding air all matter.

What supports the explanation?

What this model assumes

1. One historical sounding, one surface parcel, and a fixed 0–5 km model column. No live weather or personal location.
2. Geopotential meters are approximated as geometric vertical meters over this shallow domain.
3. The dry branch uses constant dry-air thermodynamic coefficients; the saturated branch uses liquid-water pseudoadiabatic ascent.
4. Condensate leaves the parcel calculation; there is no retained cloud-water mass, droplet count or predicted opacity.
5. No entrainment, water or ice loading, precipitation, radiation, evolving environment or resolved horizontal motion.
6. No pressure-perturbation force, drag, wind-shear organization or calculated lifting mechanism.
7. The energy required to impose the initial lifting path is outside this experiment.
8. Warm-layer changes hold observed pressure/height fixed and do not restore hydrostatic balance.
9. The first turning point ends ascent; descent is not generated by reversing the moist-ascent curve.
10. The 5 km top is the end of the modeled column, not a tropopause, predicted storm top or hard lid.
11. Actual NASA images and NOAA profile have different places and dates; they are not one observed event.
12. The original scene’s landscape and cloud cue are illustrative, not reconstructed site geometry.
13. No rain, hail, thunder, lightning or safety prediction is calculated. Follow official weather guidance for actual conditions.
14. Use the observation’s actual coordinates: The pinned source is NOAA IGRA station USM00072357, nominal May 18, 2026, 00 UTC. Heights are relative to its first valid 345 m geopotential surface. The separate 2300 release-time field is preserved without inventing a release date. A rising, drifting radiosonde is approximated as a frozen vertical profile.
15. Interpolation is an assumption: Temperature and dew point are interpolated linearly with source height; logarithmic pressure is interpolated linearly. The final source sample brackets the 5 km model limit. Missing and quality-removed required values were excluded rather than changed to zero.
16. Before and after saturation: Before saturation, the approximate parcel temperature is T₀(p/p₀)^(Rd/cp), with constant initial vapor mixing ratio. The condensation intersection is solved numerically. Above it, a pressure-coordinate liquid-water pseudoadiabatic equation is integrated with RK4 steps no larger than 50 Pa.
17. The saturated equation: dT/dp = (Rd T + Lv rs) / {p[cp + Lv² rs ε/(Rd T²)]}. Here rs is saturation mixing ratio, ε = 0.622, Rd = 287.05 J/(kg K), cp = 1004 J/(kg K), and Lv = 2.5 × 10⁶ J/kg. Constants and liquid-water treatment are approximations, not a complete mixed-phase cloud model.
18. Mixing ratio is not specific humidity: r measures kilograms of vapor per kilogram of dry air. For the vapor/dry-air mixture without condensate, Tv = T(1 + r/ε)/(1 + r). Buoyancy is B = g(Tv,parcel − Tv,environment)/Tv,environment. The units, moisture basis and omission of condensed-water loading matter.
19. A connected energy calculation: Signed buoyancy work A is the height integral of B, using a 10 m grid with linear buoyancy between points. After release at zᵣ, E(z) = 2 + A(z) − A(zᵣ), in J/kg. Two J/kg corresponds to the specified 2 m/s upward start. The first inaccessible zero ends the path; favorable conditions farther above cannot be reached by skipping that barrier.
20. Positive total work is not enough: The warm-layer calculation has positive signed net work up to 5 km, yet its 250 m release stops much lower. Summing a favorable region aloft does not show that this parcel can reach it. The displayed truncated signed integral is not full CAPE or CIN.
21. What the warming control changes: The counterfactual adds a triangular temperature increment from 500 to 2,500 m, peaking at +6 K at 1,500 m. It preserves measured pressure, height and surrounding vapor ratio. This is a sensitivity experiment, not a newly balanced atmosphere, measured cap or climate scenario.
22. What the moisture control changes: The drier case lowers the initial parcel dew point by 6 K and holds the parcel temperature and surrounding profile fixed. Its vapor ratio and density change. Its condensation level is higher, around 1,585 m, and its 250 m release stops below that level in this calculation.
23. Slow exploration is not a clock for the sky: Replay progress is parameterized by height along the connected upward path. It is not elapsed atmospheric time. We stop at the first turning point, because reversing a condensate-removing ascent would not provide a valid descent model.

What has been checked

Analytical reference cases, conservation or transition invariants, finite drawing commands, bounded setup parsing, discovery and route integrity are checked automatically. These checks do not establish anatomical fidelity, learner outcomes or browser/device compatibility. Independent subject review, learner trials, comprehensive accessibility review and browser video encoding checks remain pending.

Each source supports the associated claim. Sources do not certify this implementation or its visuals.

About the cover illustration

Actual NASA Earth Observatory satellite observation of a storm over Western Australia, January 14, 2020. NASA/Lauren Dauphin, Suomi NPP/VIIRS. Declared crop; separate from the modeled Oklahoma parcel.