You can upload and visualize more than one climate (EPW) file at a time — select multiple files at once, or upload them one after another. Each city appears as its own card above and can be compared side by side across every tab.
Climate Analyzer User Guide
1. Upload weather files
Upload one or more EPW files at once, or add them one after another. The program reads hourly dry-bulb temperature, relative humidity, wind direction, wind speed, solar radiation, and sky-cover fields. Each city appears as its own card and can be compared side by side across every tab.
Use the SI/IP toggle at the top to change displayed units (IP is the default). PMV and PPD remain dimensionless/percent values regardless of the unit setting.
2. Read each tab
Temperature: hourly and monthly dry-bulb temperature (now labeled by month), a Monthly Temperature Box Diagram (2.5th-97.5th percentile band, mean, and min/max whiskers), and an Average Daily Temperature Profile by Month diagram (each month's 24-hour cycle drawn within its own band).
Humidity: the same pairing for relative humidity - hourly/monthly charts plus a Monthly Relative Humidity Box Diagram and an Average Daily Relative Humidity Profile by Month diagram.
Wind Speed: annual, seasonal, and monthly wind-rose summaries.
Solar Radiation: compares monthly GHI, DNI, DHI, sky cover, and likely shading-needed hours.
Psychrometric Chart: plots monthly thermal-humidity profiles against the ASHRAE 55 comfort zone, lets you test passive strategies against an adjusted comfort polygon, and includes a table showing the percentage of the year within the comfort zone, broken down strategy by strategy, ending in a combined total.
Thermal Comfort: screening-level PMV/PPD, PET, UTCI, and SET* estimates, an annual UTCI stress-category chart, and monthly comfortable/no-stress hours - each with a short definition of the index or category shown.
Design Strategies: screens annual hours for broad passive and active strategy categories; when more than one city is loaded, an additional comparison table breaks every strategy category down city by city. The tab also links each strategy category to related design guidance in the 2030 Palette, with full citations.
Because two different tabs use two different comfort definitions - the ASHRAE 55 dry-bulb/humidity box on the Psychrometric tab versus the broader PMV/UTCI-based screen used elsewhere - their percentages will not always match. This is expected; each is explained where it appears.
3. Export report
Click Save Climate Analysis Report after uploading files. The exported HTML report is written as a learning and analytical tool: it opens with a glossary of terms and chart-reading guidance, then walks through every chart in the app for each city (temperature and humidity, including the box and daily-profile diagrams; the psychrometric summary and comfort-zone breakdown; solar radiation and shading; wind roses; and thermal comfort indices), each followed by a short discussion of what it shows and why it matters for design - plus a cross-city comparison section when multiple climates are loaded, and a 2030 Palette appendix with citations.
Thermal comfort indices and strategy screens are simplified screening estimates. Use validated tools for compliance, medical, or publication-grade analysis.
Upload at least one EPW file above to unlock the detailed analysis tabs.
Figure 1. Psychrometric Strategy Hours
Strategy Hours Comparison Across Uploaded Climates
Shown automatically whenever more than one EPW file is loaded. Each cell is the percentage of the year that city spends in that strategy category.
Thermal comfort definition used in these pie charts: each hour is sorted into exactly one dominant strategy category, checked in priority order. An hour is labeled "Thermal Comfort" either because it directly matches the ASHRAE 55 box (20-26°C, 30-65% RH), or - as a catch-all - because its temperature is 20-26°C and it didn't match any more specific strategy (e.g. natural ventilation, humidification). This second path means the "Thermal Comfort" share here can run higher than the strict comfort-zone percentage on the Psychrometric Chart tab.
Related Passive Strategies in the 2030 Palette
The 2030 Palette is a free, searchable library of climate-responsive design strategies ("swatches"), published by Architecture 2030 and organized across five scales — Region, City/Town, District, Site, and Building. The categories screened in the pie charts above map most closely to the Palette's Building-scale swatches, linked below for design guidance, precedent images, and technical detail beyond the screening-level percentages shown here. Rows are ordered by how many hours of the year each strategy applies, averaged across the uploaded climate file(s).
Click a zone's name in the chart legend below to show or hide just that one.
Thermal comfort zone shown on this chart (ASHRAE 55 screening approximation): operative temperature roughly 20-27°C (68-81°F) and relative humidity between 30-65%, plotted as the shaded Dynamic Comfort Zone below (adjustable by metabolic rate and clothing level). Operative temperature is approximated as the average of dry-bulb air temperature and mean radiant temperature.
Temperature Analysis
Ctrl/Cmd-click (or tap, on mobile) to compare more than one city — the box and daily-profile diagrams below now show every selected city too.
Figure 1. Hourly Dry-Bulb Temperature (°C)
Figure 2. Average Monthly Temperature (°C)
Figure 3. Average Daily Temperature Profile by Month (°C)
Each month's average 24-hour temperature cycle is drawn within its own band, from 00:00 at the left edge of the band to 24:00 at the right edge.
Figure 4. Monthly Temperature Box Diagram (°C)
Box: 95% of hourly values for the month (2.5th-97.5th percentile) · Line inside box: monthly mean · Whiskers: monthly min and max.
Humidity Analysis
Ctrl/Cmd-click (or tap, on mobile) to compare more than one city — the box and daily-profile diagrams below now show every selected city too.
Figure 1. Hourly Relative Humidity (%)
Figure 2. Average Monthly Relative Humidity (%)
Figure 3. Average Daily Relative Humidity Profile by Month (%)
Each month's average 24-hour relative humidity cycle is drawn within its own band, from 00:00 at the left edge of the band to 24:00 at the right edge.
Box: 95% of hourly values for the month (2.5th-97.5th percentile) · Line inside box: monthly mean · Whiskers: monthly min and max.
Wind Speed and Direction Analysis
Figure 1. Annual Wind Rose
Figure 2. Seasonal Wind Roses
Figure 3. Monthly Wind Roses
Solar Radiation and Cloud Cover Analysis
Ctrl/Cmd-click (or tap, on mobile) to compare more than one city. The summary table below only shows the first city selected.
Figure 1. Monthly Solar Radiation Totals (kWh/m²)
Figure 2. Monthly Average Cloud Cover (tenths)
Figure 3. Monthly Time-of-Day Shading Need
Thermal Comfort Analysis
Ctrl/Cmd-click (or tap, on mobile) to compare more than one city's original climate. Clothing sliders, passive strategies, and the comparison table below apply to the first city selected only.
Adjust any control in the panel on the right - clothing, passive strategies, or mechanical systems - and the charts and table here update immediately.
Figure 1. Monthly Mean PMV
Light green band indicates PMV thermal comfort range (-0.5 to +0.5). PMV (Predicted Mean Vote) is a thermal-sensation scale centered on 0 (neutral); the standard model is usually described as running -3 (cold) to +3 (hot), but the y-axis here is fixed to -5/+5 - the full range the underlying calculation can produce - so a month with severe enough conditions isn't visually capped at ±3.
Figure 2. Monthly Outdoor Thermal Indices (°C)
PET (Physiological Equivalent Temperature), UTCI (Universal Thermal Climate Index), and SET* (Standard Effective Temperature) each fold air temperature, humidity, wind, and radiation into one "feels-like" equivalent temperature, using different reference models - so they can disagree by a few degrees for the same hour. The light background bands mark UTCI's official thermal-stress categories (cold shades below, green "no thermal stress" in the middle, warm shades above) - they line up exactly with the UTCI line and approximately with PET/SET*, since all three sit on a similar equivalent-temperature scale.
Figure 3. Annual UTCI Stress Category Hours
UTCI stress categories (dry-bulb-equivalent °C): <-40 extreme cold · -40 to -27 very strong cold · -27 to -13 strong cold · -13 to 0 moderate cold · 0 to 9 slight cold · 9-26 no thermal stress · 26-32 moderate heat · 32-38 strong heat · 38-46 very strong heat · >46 extreme heat stress.
Figure 4. Monthly Thermal Comfortable Hours
An hour counts as comfortable/no-stress here if PMV is within ±0.5 or UTCI falls in the 9-26°C no-thermal-stress range - whichever condition is met. This differs from the ASHRAE 55 dry-bulb/humidity box used on the Psychrometric Chart tab.
Clothing Level
Summer clothing
0.50 clo
Light summer clothing
Transitional clothing
0.70 clo
Typical indoor clothing
Winter clothing
1.00 clo
Business suit / light jacket
Most Effective Passive Strategies
General Building Strategies (all seasons)
Wall insulationNone
Roof insulationNone
Window typeSingle-pane
Single+StormDoubleDbl Low-ETripleTriple Hi-Perf
Upload and select a city to show strategy options.
Upload and select a city to show strategy options.
Upload and select a city to show strategy options.