Land Information System (LIS) CONUS Soil Moisture Percentile 0-100 cm for the Washington Atmospheric River December 2025

Update Frequency: Daily Summary: Land Information System (LIS) 0-200 cm layer Soil Moisture Percentile generated by the NASA SPoRT Center over a Contiguous United States domain. The NASA Land Information System (LIS) is a high-performance land surface modeling and data assimilation system used to characterize land surface states and fluxes by integrating satellite-derived datasets, ground-based observations, and model re-analyses. The NASA SPoRT Center at MSFC developed a real-time configuration of the LIS (“SPoRT-LIS”), which is designed for use in experimental operations by domestic and international users. SPoRT-LIS is an observations-driven, historical and real-time modeling setup that runs the Noah land surface model over a full CONUS domain. It provides soil moisture estimates at approximately 3-km horizontal grid spacing over a 2-meter-deep soil column and has been validated for regional applications and against U.S. Drought Monitor products. SPoRT-LIS consists of a 33-year soil moisture climatology spanning from 1981 to 2013, which is extended to the present time and forced by atmospheric analyses from the operational North American Land Data Assimilation System-Phase 2 through 4 days prior to the current time, and by the National Centers for Environmental Prediction Global Data Assimilation System in combination with hourly Multi-Radar Multi-Sensor precipitation estimates from 4 days ago to the present time. A unique feature of SPoRT-LIS is the incorporation of daily, real-time satellite retrievals of VIIRS Green Vegetation Fraction since 2012, which results in more representative evapotranspiration and ultimately soil moisture estimates than using a fixed seasonal depiction of vegetation in the model. The 33-year soil moisture climatology also provides the database for real-time soil moisture percentiles evaluated for all U.S. counties and at each modeled grid point. The present-day soil moisture analyses are compared to daily historical distributions to determine the soil wet/dry anomalies for the specific day of the year. Soil moisture percentile maps are constructed for the model layers, and these data are frequently referenced by scientists and operational agencies contributing to the weekly U.S. Drought Monitor product. Suggested Use: This product can be used for drought assessment, fire risk assessment, potential for flooding hazards associated with heavy precipitation and high percentiles; contextualizing soil moisture content to historical values. Soil moisture percentiles are shown using a Classified Color Ramp (Multi-Color, 11-classes) that colorize the low percentile categories (≤ 30th) as shown in the U.S. Drought Monitor weekly products, ranging from yellow to dark red. The high percentile categories (≥ 70th) are colorized with increasing blue intensity. Intermediate percentiles in the 30th to 70th range are assigned a nominal gray shade. The 0-200 cm layer combines SPoRT-LIS soil moisture analyses from the top four model layers 0-10 cm, 10-40 cm, 40-100 cm, and 100-200cm. The 0-100 cm cumulative layer adjusts more slowly to precipitation episodes or the lack thereof compared to the 0-10 cm and 0-40 cm percentiles. It takes considerably longer time periods for intercepted rainfall and snowmelt to infiltrate from the upper 0-10 cm and 10-40 cm layers into the next model layer at 40-100 cm, or conversely for the deeper soil layer to dry from evapotranspiration processes. Expect anomalies of soil moisture percentiles in the 0-100 cm cumulative layer to respond on the order of weeks to months (or longer, especially during dry periods), depending on the soil classification and soil responsiveness. Data Caveats: The SPoRT-LIS is as good as the input forcing analyses, so occasional soil moisture artifacts may appear in the horizontal maps related to quality-control issues of the input datasets. These can be manifested with unusually low or high percentiles, especially along international borders, coastlines, and isolated dry “bulls-eyes” at rain gauge with quality issues. Data Visualization: The Soil Moisture Percentile is the histogram rank of the current day’s soil moisture value compared to the 33-year climatology for the present day. The percentile places into historical context the soil moisture to determine how unusually wet or dry, or typical the conditions are. Percentile thresholds as established by the drought community are used to categorize soil moisture dry anomalies as follows: Further Reference: NASA SPoRT project page: https://weather.ndc.nasa.gov/sport/ Real-time SPoRT-LIS viewer: https://weather.ndc.nasa.gov/sport/viewer/?dataset=lis_conus U.S. Drought Monitor page: https://droughtmonitor.unl.edu/ Esri REST Endpoint: See URL Section on right side of page

Update Frequency: Daily Summary: Land Information System (LIS) 0-200 cm layer Soil Moisture Percentile generated by the NASA SPoRT Center over a Contiguous United States domain. The NASA Land Information System (LIS) is a high-performance land surface modeling and data assimilation system used to characterize land surface states and fluxes by integrating satellite-derived datasets, ground-based observations, and model re-analyses. The NASA SPoRT Center at MSFC developed a real-time configuration of the LIS (“SPoRT-LIS”), which is designed for use in experimental operations by domestic and international users. SPoRT-LIS is an observations-driven, historical and real-time modeling setup that runs the Noah land surface model over a full CONUS domain. It provides soil moisture estimates at approximately 3-km horizontal grid spacing over a 2-meter-deep soil column and has been validated for regional applications and against U.S. Drought Monitor products. SPoRT-LIS consists of a 33-year soil moisture climatology spanning from 1981 to 2013, which is extended to the present time and forced by atmospheric analyses from the operational North American Land Data Assimilation System-Phase 2 through 4 days prior to the current time, and by the National Centers for Environmental Prediction Global Data Assimilation System in combination with hourly Multi-Radar Multi-Sensor precipitation estimates from 4 days ago to the present time. A unique feature of SPoRT-LIS is the incorporation of daily, real-time satellite retrievals of VIIRS Green Vegetation Fraction since 2012, which results in more representative evapotranspiration and ultimately soil moisture estimates than using a fixed seasonal depiction of vegetation in the model. The 33-year soil moisture climatology also provides the database for real-time soil moisture percentiles evaluated for all U.S. counties and at each modeled grid point. The present-day soil moisture analyses are compared to daily historical distributions to determine the soil wet/dry anomalies for the specific day of the year. Soil moisture percentile maps are constructed for the model layers, and these data are frequently referenced by scientists and operational agencies contributing to the weekly U.S. Drought Monitor product. Suggested Use: This product can be used for drought assessment, fire risk assessment, potential for flooding hazards associated with heavy precipitation and high percentiles; contextualizing soil moisture content to historical values. Soil moisture percentiles are shown using a Classified Color Ramp (Multi-Color, 11-classes) that colorize the low percentile categories (≤ 30th) as shown in the U.S. Drought Monitor weekly products, ranging from yellow to dark red. The high percentile categories (≥ 70th) are colorized with increasing blue intensity. Intermediate percentiles in the 30th to 70th range are assigned a nominal gray shade. The 0-200 cm layer combines SPoRT-LIS soil moisture analyses from the top four model layers 0-10 cm, 10-40 cm, 40-100 cm, and 100-200cm. The 0-100 cm cumulative layer adjusts more slowly to precipitation episodes or the lack thereof compared to the 0-10 cm and 0-40 cm percentiles. It takes considerably longer time periods for intercepted rainfall and snowmelt to infiltrate from the upper 0-10 cm and 10-40 cm layers into the next model layer at 40-100 cm, or conversely for the deeper soil layer to dry from evapotranspiration processes. Expect anomalies of soil moisture percentiles in the 0-100 cm cumulative layer to respond on the order of weeks to months (or longer, especially during dry periods), depending on the soil classification and soil responsiveness. Data Caveats: The SPoRT-LIS is as good as the input forcing analyses, so occasional soil moisture artifacts may appear in the horizontal maps related to quality-control issues of the input datasets. These can be manifested with unusually low or high percentiles, especially along international borders, coastlines, and isolated dry “bulls-eyes” at rain gauge with quality issues. Data Visualization: The Soil Moisture Percentile is the histogram rank of the current day’s soil moisture value compared to the 33-year climatology for the present day. The percentile places into historical context the soil moisture to determine how unusually wet or dry, or typical the conditions are. Percentile thresholds as established by the drought community are used to categorize soil moisture dry anomalies as follows: Further Reference: NASA SPoRT project page: https://weather.ndc.nasa.gov/sport/ Real-time SPoRT-LIS viewer: https://weather.ndc.nasa.gov/sport/viewer/?dataset=lis_conus Daily animations of experimental 2-week forecasts of SPoRT-LIS soil moisture percentiles: https://geo.nsstc.nasa.gov/SPoRT/modeling/lis/conus3km/forecasts/ NASA Land Information System project page: https://lis.gsfc.nasa.gov/ U.S. Drought Monitor page: https://droughtmonitor.unl.edu/ Esri REST Endpoint: See URL Section on right side of page

Date of Image(s): December 8; December 9; December 12; December 13; December 14; December 15; December 17 Date of Next Image: Typically, there are two daytime images expected each day around 1:00pm EST. Summary: Floodwater derived from Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard NASA and NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) satellite. VIIRS floodwater product was produced by NASA SatCORPS Ground Station Observation Network (GSON) low latency system.. The image shows where floodwater was detected from the VIIRS observation. Suggested Usage: The floodwater fraction percentage (1-100%) that contains water Satellite/Sensor/Resolution: 375m spatial resolution VIIRS instrument onboard SNPP Satellite Generated using CSPP v4.1 Credits: Image Credit: NASA Langley SatCORPS Louis Nguyen of NASA Langley SatCORPS: https://satcorps.larc.nasa.gov/new/ NOAA Joint Polar Satellite System (JPSS) VIIRS Data: https://registry.opendata.aws/noaa-jpss/ Additional information on VIIRS Flooding products: https://disasters-geoplatform.hub.arcgis.com/pages/viirs-floodwater-fraction-map/

Dates of Images: Post-Event: December 17, 2025 Pre-Event: October 13, 2025 Date of Next Image: Unknown Summary: Modified Normalized Difference Water Index (MNDWI) provides a different view of the Earth's surface combining different bands to make water bodies more obvious. This index can be used to identify flooded areas as well as heavily saturated areas. Suggested Use: For mNDWI, areas of existing water, such as a rivers or lakes appear in the darkest green with high values near 1, while dry land appears in the darkest brown with low values near -1. This product can be used to identify potentially flooded areas that can be seen in varying shades of green and light brown depending on the amount of moisture picked up by the satellite. Note: Areas of cloud cover will show up in varying shades of green/blue similar to water. Satellite/Sensor: MultiSpectral Instrument (MSI) on European Space Agency's (ESA) Copernicus Sentinel-2A/2B satellites Resolution: 10 meters Credits: NASA/MSFC, USGS, ESA Copernicus Esri REST Endpoint: See URL to the right. WMS: https://gis.earthdata.nasa.gov/portal/services/DISASTERS_202512_FLOOD_WA/2512_sentinel2_mndwi/ImageServer/WMSServer

Summary: The Advanced Rapid Imaging and Analysis (ARIA) and Observational Products for End-Users from Remote Sensing Analysis (OPERA) teams at NASA's Jet Propulsion Laboratory and California Institute of Technology created maps of surface water extent impacted by the flooding caused by Atmospheric Rivers in the Pacific Northwest starting on December 8, 2025 using the OPERA Dynamic Surface Water Extent from Sentinel-1 (DSWx-S1). The results posted here are preliminary and unvalidated results, primarily intended to aid the field response and provide a rough first look at the inundation extent. The ARIA-share website has always focused on posting preliminary results as fast as possible for disaster response. All information is provisional for use under emergency response guidelines. These data are provided with absolutely no warranty of any kind. Use at your own risk. OPERA DSWx-S1 The OPERA DSWx-S1 was used to identify surface water for the flooding event. The images provided are a mosaic of OPERA DSWx-S1 products, producing a composite image for each date. The mosaicking applied prioritized pixels classified as open surface water and inundated vegetation to preserve water pixels in regions of product granule overlap. The images are provided as GeoTIFF files. Water (WTR) Layer Description: Masked interpreted water classification layer. This represents pixel-wise classification into one of three water classes (not water, open water and inundated vegetation), masks (HAND mask and layover/shadow mask), or no data classes. Water (WTR) Layer Values: 0: Not Water - an area with valid data that is not open water (class 1), inundated vegetation (class 3), height above nearest drainage masked (class 250), or layover/shadow masked (class 251). Masking can result in "not water" (class 0) where land cover masking is applied (suggested color: #ffffff) 1: Open Water - an area that is entirely water and unobstructed to the sensor, including obstructions by vegetation, terrain, and buildings. (suggested color: #0000ff) 3: Inundated vegetation - an area that is considered inundated, extracted from the high value in dual polarization ratio and the wetland class in land cover map. (suggested color: #00ff00) 250: Height Above Nearest Drainage (HAND) masked - an area where topographic height is higher than the HAND threshold (suggested color: #c8c8c8) 251: Layover/shadow masked - an area identified as layover or shadow computed from the geometry of the digital elevation model and sensor. The area is directly copied from input burst RTC-S1 products (suggested color: #808080) 255: No data (suggested color: transparent) Water Gain Description: Water gain classification layer. This represents pixel-wise classification into water gain and no change/water loss, as well as no data classes. Water Gain Layer Values:0: No Change or Water Loss- an area that had no change (e.g., open water in both images) or water loss (e.g., open water to not water). Masked pixels from HAND and Layover/Shadow are set to No data. (suggested color: #ffffff) 1: Water Gain - an area that gained water in the most recent image. This includes change from Not Water to Inundated Vegetation, Not Water to Open Water, and Inundated Vegetation to Open Water. (suggested color: #ff15e4) Satellite/Sensor: Synthetic Aperture Radar (SAR) instrument on European Space Agency's (ESA) Sentinel-1A/C satellite. Resolution: 30 meters OPERA DSWx-S1 data availability The post-processed products are available to download at https://aria-share.jpl.nasa.gov/20251210-PacificNorthwest-AtmRiver/DSWx-S1//. The OPERA DSWx-S1 products have been in production since September 2024, are freely distributed to the public via NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC), and can be downloaded through NASA's Earthdata search. For more information about the Dynamic Surface Water eXtent product suite, please refer to the DSWx Product page: https://www.jpl.nasa.gov/go/opera/products/dswx-product-suite. For more information about the Caltech-JPL ARIA project, visit https://aria.jpl.nasa.gov. For more information about the JPL OPERA project, visit https://www.jpl.nasa.gov/go/opera/. Product POCs: Cole Speed (cole.speed@jpl.nasa.gov) Mary Grace Bato (bato@jpl.nasa.gov) Ines Fenni (ines.fenni@jpl.nasa.gov) Emre Havazli (emre.havazli@jpl.nasa.gov) Alexander Handwerger (alexander.handwerger@jpl.nasa.gov) WMS Endpoint: https://gis.earthdata.nasa.gov/portal/services/DISASTERS_202512_FLOOD_WA/2512_opera_dswx_s1/MapServer/WMSServer Data Download: https://aria-share.jpl.nasa.gov/20251210-PacificNorthwest-AtmRiver/DSWx-S1/ Credits: Sentinel-1 data were accessed through the Copernicus Open Hub and the Alaska Satellite Facility server. The product contains modified Copernicus Sentinel data (2025), processed by the European Space Agency and analyzed by the NASA-JPL/Caltech ARIA and OPERA team. The products are produced as part of the OPERA project, which is funded by NASA to address remote sensing needs identified by the Satellite Needs Working Group, and managed by NASA's Jet Propulsion Laboratory. NASA JPL-Caltech ARIA/OPERA Team ==================  Image acquisition times in UTC (local): 2025-12-17 2:00AM (local Pacific Time: 2025-12-16 6:00PM),  2025-12-15 2:00AM (local Pacific Time: 2025-12-14 6:00PM),  2025-12-14 2:00PM (local Pacific Time: 2025-12-14 6:00AM),  2025-12-11 2:00AM (local Pacific Time: 2025-12-10 6:00PM),  2025-12-10 2:00AM (local Pacific Time: 2025-12-09 6:00PM),  2025-12-07 2:00PM (local Pacific Time: 2025-12-07 6:00AM),  2025-12-05 2:00AM (local Pacific Time: 2025-12-04 6:00PM),   2025-12-02 2:00PM (local Pacific Time: 2025-12-02 6:00AM),  2025-11-29 2:00AM (local Pacific Time: 2025-11-28 6:00PM),   2025-11-28 2:00AM (local Pacific Time: 2025-11-27 6:00PM)  Last Update 23 Dec. 2025

Rasters/CONUS_NLCD_10yr_intervals