Site characteristics: Soil moisture summary for 376 SNOTEL station locations

Satellite-based synthetic aperture radar (SAR) has been used to assess and quantify snowmelt across large spatial and temporal scales. While there have been recent advancements in SAR-based snow water equivalent (SWE) retrieval methods, obtaining accurate estimates of SWE requires knowledge of the amount of liquid water content in the snowpack given its strong impact on radar velocity. Recent studies have utilized Sentinel-1 SAR to identify snowmelt runoff onset in complex, high-elevation terrain based on a seasonal minimum backscatter time-series, however, detailed investigations into the snowpack state before and after snowmelt runoff onset are lacking. In this study, we integrated repeat field measurements, SNOw TELemetry (SNOTEL) station data (n = 260) from across the western U.S., and paired Sentinel-1 SAR estimates of snowmelt runoff onset to 1) assess the snowpack state prior to and after Sentinel-1 SAR-derived runoff onset estimates, and 2) evaluate Sentinel-1 SAR estimates of r..., , # Site characteristics: Soil moisture summary for 376 SNOTEL station locations

Dataset DOI: [10.5061/dryad.bvq83bkm9](10.5061/dryad.bvq83bkm9)

## Description of the data and file structure

**Summary of dataset:**

The following dataset (SNOTEL_Summary_Data.csv)  includes metadata, terrain, SNOTEL soil moisture, peak SWE, and Sentinel-1 SAR summary data for 376 SNOTEL stations across the western U.S. A subset of these stations (260) was used in Detre et al., 2025 in a paired comparison with Sentinel-1 SAR estimates of snowmelt runoff onset.

**Description of file structure and contents:**

Each SNOTEL station (site_id column) included in this dataset contains 35 columns of summary characteristics. A subset of these stations (54) do not have precise coordinates, while the majority (322) have precise coordinates found using high-resolution optical imagery in Google Earth Pro in addition to the publicly available coordinates.

**VARIABLES:**

* X = Row number

* state = state (two-letter...,