Weather Charts - Current Weather Products - Observations & Forecast Charts

Nov 1, 2026

Weather Charts summarizes current weather products used for aviation planning and short-term decision-making. It explains observations tools including surface analysis charts and constant pressure charts, detailing what each chart depicts (sea level pressure, fronts, winds, temperatures, dew points, sky cover, and tropical waves). It covers forecast chart types, issuance timing, validity windows, and how to read key symbols such as high/low centers, pressure trends, and front movement indicators, plus altitude-to-mb context for 3D interpretation.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages41

Reading Time1 h 43 min

AccessFree to download

Weather Charts

Current Weather Products

Observations

Forecast Charts

Surface Analysis Chart

Key elements and interpretation

Constant Pressure Charts

Altitude mapping and guidance

Weather Charts Current Weather Products • Observations – Surface Analysis Charts – Constant Pressure Charts – Weather Depiction Charts – Lifted Index Charts – Radar Summary Charts • Forecast Charts – Short Range Surface Prognostic Chart – Low level Significant Weather Prognostic Chart 2 Surface Analysis Chart • Shows the “big picture” – helps plan flights around WX • Depicts – Sea level pressure – Position of highs, lows, ridges and troughs – Position of fronts – Position of boundaries – Overview of winds, temperatures and dew points • Issued every 3 hours • Valid for 6 hours • Available at: [http://www.hpc.ncep.noaa.gov/html/sfc2.shtml](http://www.hpc.ncep.noaa.gov/html/sfc2.shtml) 3 Surface Analysis Chart Cold front – Pips show direction of movement Warm front stationary front Data High -Number adjacent is central pressure Low Sea Level Pressure –4mb interval lines -Line below \# is pressure trend Temp Dew Point Wind Sea Level pressure (first 10 or 9 digits omitted) or ceiling height Sky cover – If station symbol is square then automated data was used Tropical wave 4 Surface Analysis Chart 5 Surface Analysis Chart 6 Surface Analysis Chart 7 Surface Analysis Chart 8 Constant Pressure Charts • Similar to the surface analysis chart but at different pressure levels (altitudes will vary) – 850 MB chart ≈ 5,000’ – 700 MB chart ≈ 10,000’ – 500 MB chart ≈ 18,000’ • Provides a 3D view of large areas – interpolate between charts • Data gathered through balloons • Shows winds and temps – can identify jetstream / freezing risks for example • Charts available at: [http://aviationweather.gov/std_brief/](http://aviationweather.gov/std_brief/) 9 Constant Pressure Charts Issue date/ time X Marks high/low center Wind Level Some charts also show: isotherms – areas of equal temperature – bold dashed line isotachs – constant wind speed areas – short fine dashed line with K Contour line area of = height in meters (850 MB omits 1 before and 700 omits 2 or 3 before – which ever makes the number closer to 3,000 meters) e.g. 309 = 3309 meters or 10,754’ – Look at gradients -wind speed proportional to gradients (close = high winds) . Contours can be interpreted in the same manner as isobars on the surface chart (e.g. high altitude=high pressure area) 10

FAQs

What is the main purpose of surface analysis charts for users?

Surface analysis charts show the overall “big picture” to help plan flights around weather (WX) by depicting sea level pressure, highs/lows, ridges/troughs, fronts, boundaries, and an overview of winds, temperatures, and dew points.

How often are surface analysis charts issued, and how long are they valid?

Surface analysis charts are issued every 3 hours and are valid for 6 hours.

What do constant pressure charts add beyond surface analysis charts?

Constant pressure charts provide a 3D view at different pressure levels using balloon-gathered data, showing winds and temperatures and helping identify risks such as jetstream or freezing conditions.

Nov 1, 2026

Uploaded by CatatanPagi