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Comparing 48 American dropzones

Dropzones in America and its territories have an extremely wide range of seasonally varying conditions that can affect skydiving in various ways. A jumper who learned at a coastal dropzone in the winter at a low elevation may be surprised at the speed of landings when visiting a high-altitude dropzone the following summer. In order to gain a better understanding of the spectra of parameters and their interrelationships, we look at some extremes like peak and lowest seasonal density altitude as well as more general factors such as how often a dropzone has clear skies, and a measure of how urban it is. Data is drawn from decades of federal observations—NOAA climate normals at each field’s elevation, archived METARs, weather balloons, and the national land-cover satellite survey—never forecasts; the notes below detail each. Click any column to re-rank. Click any dropzone to open it in the airport explorer to gain more detailed information. And enter any other dropzone's airport below to see where it fits.

How this was computed. For each field: the nearest NOAA 1991–2020 climate-normals station’s typical 3 p.m. temperature and dewpoint for the 15th of every month—thirty years of averaged observations, never a forecast—lapse-adjusted to the field’s elevation, then converted to density altitude with the same three-step form as our density altitude calculator. The scale turns full red at 5,000 ft, the level aviation conventionally treats as high density altitude. Three entries lean on distant or much-lower stations and carry the roughest estimates: Mesquite (Cedar City, 80 mi, adjusted −3,600 ft), Yosemite (Fresno, 54 mi, +1,900 ft), and Moab (Grand Junction, 70 mi). Puerto Rico is the one exception to the normals: NOAA publishes no hourly normals for the island, so Arecibo’s climate is computed directly from ten years of that station’s own mid-afternoon METAR observations—a shorter record of the same kind. Guam sits outside every land-cover product, so its Built-up (measure of urbanness) cell remains empty, as does Phoenix’s uppers cell—its balloon record is too thin to claim, the same refusal Eloy’s thin months get. Maui lacks the most information: Hāna has no weather station, and the nearest METAR sits at Kahului—across the island’s rain shadow, a different climate regime entirely—so Maui’s surface-wind, sky, and wet columns stay blank rather than describe the dry side of a wet place. A station blind to precipitation (West Tennessee’s) likewise reports nothing rather than a fictional zero. An amber * marks a cell whose source station sits notably far from the field—climate normals 50 miles or more, weather balloons 100 or more, the surface station 25 or more; the tooltip names the station and the miles. Wind is its own record: every archived METAR of the last ten years (NOAA ASOS network via the Iowa Environmental Mesonet), solar-afternoon observations only, giving each field’s mean afternoon wind—hover the column for two more: the share of observations at or under USPA’s 14 mph (12.2 kt) student wind limit, and the share where gusts exceeded the sustained wind by more than 7 kt (an amber G marks fields where that spread occurs in 15% or more of observations). Top gust is the strongest afternoon gust in the ten-year record. Clear skies is the share of afternoon observations with no broken or overcast layer (or obscured sky) below 12,000 ft AGL—the skies skydiving operations can legal occur through (FAR 105.17); 12,000 ft is as high as automated ceilometers can reach, so a deck between there and a 13,500 ft exit cannot be considered. Uppers come from the deepest record on this page: NOAA’s Integrated Global Radiosonde Archive—actual weather balloons, launched at 00Z—7–8 p.m. Eastern through 4–5 p.m. Pacific, the closest sounding to the mainland afternoon; 2 p.m. in Hawaii, mid-morning on Guam—from stations whose records reach back as far as 1919. We average 2016–2025 monthly means of the wind at the mandatory pressure levels that fall inside each field’s own bands—the freefall band (3,500–13,500 ft above the field, exit to pull) and the canopy band (the surface up to 3,500 ft)—from the nearest sounding station, named with its distance in each cell’s tooltip. The two are nearly independent across the roster: the freefall band is influenced primarily by the jet stream and the season, the canopy band by the boundary layer—trades, sea breezes, terrain—so one can be high while the other is low (see list above's greatest band shear and most inverted column). The canopy band is the coarser measure, catching only one or two mandatory levels—and at high-elevation fields (the Front Range, the Grand Canyon) it catches none: 850 hPa sits underground there and 700 hPa floats just overhead, so those cells remain empty rather than extrapolated. Fields whose station record covers fewer than nine months of the year say “thin record” rather than report an average the data cannot support. Wet afternoons comes from the same ten-year METAR sweep: the share of solar-afternoon observations reporting precipitation or a thunderstorm at the field—the afternoons the sky takes back regardless of ceilings, which is the reason why it and Clear skies are separate columns. Terrain relief samples ~70 surveyed elevations (USGS 10-meter data; NASA SRTM where it does not reach) across the same 3-mile circle and reports the 5th-to-95th-percentile spread—robust to a lone tower or pit. It exists because terrain reads flatter from above than it lands: the circle is our stated approximation, since no table can know where any jump actually ends. Built-up measures urbanness and the ground itself: USGS’s National Land Cover Database (30-meter satellite-derived classification, 2021 for the Lower 48, 2016 for Alaska), tallied over a 3-mile circle around each field. The column counts developed land of low, medium, or high intensity; hover for the full profile (forest, water, open land). It describes the neighborhood’s character, not any particular field’s clearness. Islands beyond NLCD’s reach (Hawaii, Puerto Rico) are read from NOAA’s C-CAP regional land cover instead—the coastal cousin of the same satellite classification; Guam sits outside both products and therefore shows none. For clarity: the word afternoon is used here in a few different ways: afternoon means the 12:00–17:59 solar-time window for the surface records (METARs are continuous), the 3 p.m. slice for the climate normals (an hourly product), and the 00Z sounding for the balloons (launched twice a day)—each source’s closest approach to mid-afternoon. Why afternoons, when so much jumping happens in the morning? Because mornings run calm, cool, and dense nearly everywhere—sample them and the whole roster converges; afternoons are when density altitude, wind, and convection peak and dropzones actually differ most, which is the entire point of our comparison's aim of establishing a spectrum.

This page describes various external characteristics of dropzones from an objective perspective with the goal of promoting a better understanding of variations between them—it is not a ranking of quality, safety, or anything else a dropzone controls, and typical values say nothing about any particular day (check current conditions in the airport explorer). Nothing here is a substitute for proper training by certified instructors. See, for example, the United States Parachute Association's Integrated Student Program, described in the Skydiver's Information Manual.