Documentation

NOAA National Centers for Environmental Information (NCEI) — All temperature and precipitation data is sourced from the NCEI Daily Summaries dataset via their public API.

• API Endpoint: https://www.ncei.noaa.gov/access/services/data/v1
• Dataset: daily-summaries
• Data Types: TMIN (daily minimum temperature), TMAX (daily maximum temperature), PRCP (daily precipitation)
• Units: Standard (°F for temperature, inches for precipitation)

Geocoding — Nominatim / OpenStreetMap — Location lookups (ZIP code, city/state) are resolved to latitude and longitude coordinates using the Nominatim geocoding service. Results are cached in Cloudflare Workers KV for 24 hours.

Station Data — A curated set of US weather stations (from NOAA GHCN) is stored in stations.json. This is used for nearest-station lookups.

EntoTools uses the modified Growing Degree Day (mGDD) method, also known as the "modified sine" or "simple average" method with an upper threshold cap.

Formula

Parameters

• Base Temperature (default 50°F): The lower developmental threshold. Days where the average temperature is below this contribute 0 GDD.
• Max Temperature Cap (default 86°F): The upper developmental threshold. TMAX values above this are capped at this value before averaging, because insect development typically plateaus or ceases above certain temperatures.
• Accumulation Start Date: The month and day (e.g., Jan 1) when cumulative GDD resets and begins accumulating for the season.

Accumulation Logic

• Cumulative GDD resets to 0 at the start of each calendar year.
• Daily GDD only accumulates on or after the configured accumulation start date.
• Before the accumulation start date, cumulative GDD remains 0.

Occasionally, a weather station may fail to report temperature data for a given day. When this happens, the GDD calculation uses the following interpolation method:

• Interpolated values are tagged as Calculated in the data tables and charts.
• If both adjacent days are also missing data, the day contributes 0 GDD (no cascading interpolation).
• This ensures the cumulative GDD total remains as accurate as possible even with occasional single-day data gaps.

When a date range extends to or near the present day, the system generates a 30-day forecast to project future GDD accumulation.

Method

• Linear Trend: A linear regression is computed from the observed temperature data to capture the current trend.
• Seasonal Normals: The system fetches 5 years of historical data for the station and computes day-of-year averages, smoothed with a 7-day moving average.
• Blended Forecast: For each forecast day, the predicted average temperature combines the linear trend with a seasonal adjustment (how that day-of-year typically deviates from the overall mean). The daily range (TMAX − TMIN) is estimated from the seasonal normal for that day.

Forecast values are tagged as Forecast in tables and displayed with dashed lines on charts.

The Degree Day Calculator is the primary tool for exploring weather data and GDD trends over custom date ranges.

How to Use

1. Select a location using ZIP code, city/state, or latitude/longitude coordinates.
2. Add date ranges — you can compare multiple time periods side-by-side. Each range appears as a separate series on the charts.
3. Configure GDD parameters: base temperature, max temperature cap, and accumulation start date (month and day).
4. Click Search — data is fetched from the nearest NOAA station and displayed.

Available Charts & Data

• Temperature Chart: Daily high/low temperatures with actual data as solid lines and forecast as dashed lines.
• GDD Chart: Cumulative and daily GDD values. Toggle forecast visibility on/off.
• Precipitation Chart: Daily and cumulative precipitation (actual data only).
• Data Tables: Detailed breakdowns for temperature, GDD, and precipitation in tabular format.

Saving Searches

Search results can be saved to your browser's local storage for quick access later. Saved searches appear in the sidebar and can be loaded or deleted.

The GDD Lookup provides a quick way to get the cumulative GDD value for a specific location and target date.

How to Use

1. Select a location using ZIP code, city/state, or lat/lon.
2. Set the target date — defaults to today.
3. Configure GDD parameters (base temp, max cap, accumulation start).
4. Click Look Up — the system fetches data from the accumulation start date to the target date and computes cumulative GDD.

Results

The result card shows cumulative GDD, daily GDD for the target date, average temperature, station info, and a full day-by-day breakdown table.

The Label Data tool helps generate printable specimen labels, field notes, and CSV exports for entomological collections.

How to Use

1. Fill in collection details: collector name, location, date range, habitat, collection method, and specimen information.
2. Add entries to a label sheet — each entry represents a collection event.
3. Generate outputs: printable labels formatted for pinning, field notes, or CSV files for database import.

Data Persistence

Label sheet data is stored in your browser's local storage. It persists between sessions but will be lost if you clear your browser cache.

The Collection Database lets you browse, search, and manage all saved specimen collection records.

Features

• Browse & Sort: View all records sorted by date, location, or other fields.
• Search: Filter records by keyword across all fields.
• Export: Download all records as a CSV file for backup or import into other systems.
• Import: Upload a CSV file to restore or add records to the database.

When you search for a location, the system automatically finds the best nearby weather station:

1. Bounding Box Filter: Stations within approximately 140 miles (2° latitude) of the search location are pre-filtered.
2. Distance Ranking: Remaining stations are ranked by haversine distance.
3. Station Type Priority: Stations with IDs starting with USW (airports), USC (cooperative), or USR (regional) are preferred, as they are more likely to report temperature data.
4. Data Verification: The top candidates are checked against NCEI for recent data (last 30 days). The closest station with actual data is selected.

The selected station's name, ID, and distance from your search location are displayed in the results.

• Data Availability: NOAA NCEI data may have a 1–3 day lag from the current date. The most recent days might not have data yet.
• Station Coverage: Rural areas may have fewer nearby stations, resulting in data from stations farther away. Always check the reported distance, as it is listed in the datasets provided..
• Forecast Accuracy: The 30-day forecast is a statistical projection based on trends and seasonal normals — it is not a meteorological forecast. Accuracy decreases for dates further in the future.
• Local Storage: Saved searches, label sheets, and the collection database are stored in your browser. They do not sync across devices and can be lost if you clear browser data. We recommend either printing your data and charts, saving the CSV files, and exporting the database when leaving the page. You can re-import the Database CSV file when you return.
• US Only: The geocoding and station data are currently limited to United States locations.
• NCEI Rate Limits: The NCEI API may occasionally return 503 errors during high-traffic periods. The system automatically retries up to 3 times with exponential backoff.