Weather Delay Calculator: Delay Days, Makeup Cost, and Climate Region Analysis

How It Works

1. Select Climate Region

   Choose from 7 climate regions (Northeast, Southeast, Gulf Coast, Midwest, Mountain West, Pacific Northwest, Desert Southwest). Each region loads historical average weather day data as the baseline for planning.

2. Set Project Duration and Dates

   Enter the project start date, planned duration in work days, and the current date. The calculator determines which months your project spans and applies seasonal weather patterns.

3. Enter Actual Weather Delays

   Log actual weather delay days by type as they occur: rain, snow/ice, extreme cold, extreme heat, high wind, and lightning. The calculator tracks cumulative delays against the regional baseline.

4. Review Delay vs Baseline

   See whether your actual weather delays are above or below the historical average for your region and project timeframe. The weather tracking bar shows cumulative delay days visually.

5. Compare Delay Cost vs Makeup Cost

   Enter daily general conditions cost (supervision, equipment rental, trailers, etc.) and overtime premium rates. The calculator compares the cost of absorbing the delay against the cost of weekend or extended-day makeup work.

6. Review Weather Type Breakdown

   The pie chart shows which weather types caused the most delays. Use this to target mitigation strategies or justify time extension requests with detailed weather documentation.

Built For

• General contractors building weather contingency into bids using historical climate data instead of guessing
• Project managers documenting weather delays day by day for time extension requests and liquidated damages defense
• Schedulers updating the CPM schedule with actual weather delay data and replanning recovery activities
• Construction executives comparing delay costs across multiple projects to identify which regions and seasons have the highest weather risk
• Estimators pricing weather protection measures (heated enclosures, dewatering, wind screens) against expected delay costs
• Owners evaluating contractor time extension requests by comparing claimed weather days against historical averages for the project location
• Surety bond underwriters assessing schedule risk for construction performance bonds based on seasonal weather exposure

Features & Capabilities

7 Climate Region Presets

Regional weather day averages for Northeast, Southeast, Gulf Coast, Midwest, Mountain West, Pacific Northwest, and Desert Southwest. Based on historical NOAA data for construction-relevant weather conditions.

Weather Day Tracking Bar

Visual progress bar showing cumulative weather delay days against the project baseline. Green when below average, yellow when approaching average, red when exceeding average.

Delay vs Makeup Cost Comparison

Compares the cost of accepting the schedule delay (extended general conditions) against the cost of recovering lost days through overtime and weekend work. Shows the break-even point.

Weather Type Breakdown Chart

Pie chart showing the percentage of delays by weather type (rain, snow, cold, heat, wind, lightning). Identifies which conditions are causing the most impact for targeted mitigation.

Seasonal Pattern Display

Shows expected weather days by month for the selected region so you can schedule weather-sensitive work during the driest or mildest periods.

PDF Export for Documentation

Export the complete weather delay log and analysis as a PDF for contract documentation, time extension requests, and project close-out records.

Frequently Asked Questions