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Winter Storm of January 31 – February 3, 2021

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forty°seventy

Winter Storm of January 31 – February 3, 2021

Winter Storm of January 31 – February 3, 2021

Chapter 1 · A slow storm

A slow storm crawls up the coast.

The replay opens as the snow begins in the Mid-Atlantic.

12:00UTC · Sun, Jan 31, 2021 · 7:00 AM EST

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Replay of past events. For current weather and warnings, see weather.gov. Links are rule-based facts. About and credits

Replay · WS20210131

Winter Storm of January 31 – February 3, 2021: the story

Jan 31, 12:00 UTC – Feb 3, 12:00 UTC. Radar showing snow and rain, winter warnings, storm reports and the surface low's track from the Weather Prediction Center, in order. NCEI's Northeast Snowfall Impact Scale rates it Category 3, Major (NESIS 4.93), and ranks it 26th on its list.

  • 168 NWS warnings
  • 8,488 storm reports
  • 24 WPC surface-low analyses
  • 8 FAA airport programs
  • 7 rule-based links
  • 433 radar frames, 10 min apart

A slow storm

Jan 31–Feb 1

The replay opens as the snow begins in the Mid-Atlantic.

Replay from here

Wind on the Cape

Feb 2

  1. The strongest wind reported: 64 mph at Wellfleet, MA.Replay from here

The snow totals

Feb 2–3

  1. The largest snow report: 35.5 in at Nazareth, PA.Replay from here
  2. The low is at its deepest: 986 mb.Replay from here

How we link records

RuleWhat it checksLinks
R2 dashedAn airport program inside a warning that had been in effect for over 60 min (context)7

Solid lines mark rules that passed an independent check; dashed lines are context. Links are rule-based facts: each shows two records that overlap in place and time. How we know

Where this storm's data comes from

Every layer, the provider behind it and the period it covers.

LayerProviderPeriodRecords
MRMS SeamlessHSRNOAA/NSSL via Iowa Environmental MesonetJan 31, 12:00 UTC – Feb 3, 12:00 UTC433
NWS storm-based warning polygonsNOAA National Weather Service via Iowa Environmental MesonetJan 31, 12:00 UTC – Feb 3, 12:00 UTC168
NWS Local Storm ReportsNOAA National Weather Service via Iowa Environmental MesonetJan 31, 12:00 UTC – Feb 3, 12:00 UTC8,488
WPC coded surface bulletinsNOAA Weather Prediction Center via Iowa Environmental MesonetJan 31, 12:00 UTC – Feb 3, 12:00 UTC24
NOHRSC snowfallNOAA National Operational Hydrologic Remote Sensing CenterJan 31, 12:00 UTC – Feb 3, 12:00 UTC
FAA airport programs (ground stops and ground delay programs)FAA Air Traffic Control System Command CenterJan 31, 12:00 UTC – Feb 3, 12:00 UTC8
  • Radar: NOAA/NSSL MRMS SeamlessHSR, via the Iowa Environmental Mesonet (IEM), Iowa State University
  • Warnings: NOAA/NWS, storm-based polygons via the Iowa Environmental Mesonet
  • Storm reports: NOAA/NWS Local Storm Reports via the Iowa Environmental Mesonet
  • Storm track: NOAA/NWS Weather Prediction Center coded surface bulletins, via the Iowa Environmental Mesonet
  • Airport programs: FAA Air Traffic Control System Command Center
  • Filings: U.S. Securities and Exchange Commission EDGAR
  • Snowfall: NOAA/NWS National Operational Hydrologic Remote Sensing Center (NOHRSC)