Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS) Field Campaign
The Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS), funded by NASA’s Earth Venture program, is the first comprehensive study of East Coast snowstorms in 30 years. IMPACTS will fly a complementary suite of remote sensing and in-situ instruments for three 6-week deployments (2020-2022) on NASA’s ER-2 high-altitude aircraft and P-3 cloud-sampling aircraft. The first deployment began on January 17, 2020 and ended on March 1, 2020. IMPACTS samples U.S. East Coast winter storms from advanced radar, LiDAR, and microwave radiometer remote sensing instruments on the ER-2 and state-of-the-art microphysics probes and dropsonde capabilities on the P-3, augmented by ground-based radar and rawinsonde data, multiple NASA and NOAA satellites (including GPM, GOES-16, and the Joint Polar Satellite System (JPSS)), and computer simulations. 
Note: This micro article will be periodically updated as GHRC publishes more data and as new flights and IMPACTS publications occur.

Scientific Objectives

The primary objectives of IMPACTS included:

  • Provide observations critical to understanding the mechanisms of snowband formation, organization, and evolution
  • Examine how the microphysical characteristics and likely growth mechanisms of snow particles vary across snowbands
  • Improve snowfall remote sensing interpretation and modeling to significantly advance prediction capabilities
IMPACTS Coverage Map
Spatial Coverage
[N: 45, W: -81, E: -66, S: 35] degrees
Time Range
mid-January through February 2020-2022
Snow Storms
Snow Microphysics

Instruments Used

Multiple instruments were utilized during the IMPACTS field campaign to sample disruptive East Coast US snowfall and winter storms. The IMPACTS airborne instrument suite combines advanced radar, lidar, and microwave radiometer remote sensing instruments on the ER-2 with state-of-the-art microphysics probes and dropsonde capabilities on the P-3. The instruments on the ER-2 include the Cloud Radar System (CRS), the High-altitude Imaging Wind & Rain Airborne Profiler (HIWRAP), the ER-2 X-Band Doppler Radar (EXRAD), the Conical Scanning Millimeter-wave Imaging Radiometer (CoSMIR), the Advanced Microwave Precipitation Radiometer (AMPR), and the Cloud Physics Lidar (CPL). The instruments on the P-3 include the Cloud-Droplet Probe (CDP), the Cloud, Aerosol and Precipitation Spectrometer (CAPS), the 2D-S Probe (2D-S), the High Volume Precipitation Sampler-3 (HVPS-3), the Nevzorov Probe (Nevzorov), the King Probe (King), the Hawkeye Probe (Hawkeye), the Rosemount Icing Probe (RICE),  the Water Isotope System for Precipitation and Entrainment Research (WISPER), the Turbulent Air Motion Measurement System (TAMMS), the Advanced Vertical Atmospheric Profiling System (AVAPS), and the Particle Habit Imaging and Polar Scattering probe (PHIPS). 
Ground-based instruments include radars, rawinsondes, ceilometers, and Microwave Radiometer (MWR).
IMPACTS Instruments
IMPACTS uses coordinated remote-sensing ER-2 and in-situ sampling P-3 flights to study the structure, dynamics, and microphysical characteristics of banded structures in winter storms. Merging ER-2 multi-sensor data (CPL, HIWRAP, and AMPR, shown above) enables advanced retrievals of microphysical properties of snowbands. (Source: Earth Science Project Office IMPACTS webpage)









Radar reflectivity

Doppler velocity


Brightness Temperature


Water vapor



Optical depth

Particle size distribution

Particle concentration















Ground  based

Ground based






NEXRAD Mosaic Midwest IMPACTS: 
Mobile UIUC Soundings IMPACTS: 
NOAA Soundings IMPACTS: 
SBU Soundings IMPACTS: 
Two-Dimensional Video Disdrometer (2DVD) IMPACTS:
Autonomous Parsivel Unit (APU) IMPACTS:

Radar reflectivity

Doppler velocity

Atmospheric pressure, temperature, water vapor, and winds








Events of Interest

This section highlights events within the field campaign of particular scientific interest.

IMPACTS Timeline

Major Findings

Updates will be made to this micro article throughout the field campaign.

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Oct 23rd, 2020
Lucy Wang
Field Campaign

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