Storm Mode wall: North Dakota

Map

Freeze Warning 2
Frost Advisory 1

NWS’s polygons as issued, or the zones a zone-issued alert names; SPC’s watches by their counties. Checked 03:07Z. Data: NOAA/NWS, NOAA/SPC.

In force in this area 3

Freeze Warning22 not yet in effect · until 14:00Z
Frost Advisory11 not yet in effect · until 14:00Z

Every alert in this area, most urgent first

Freeze WarningTraverse; Big Stone; Codington; Grant; Hamlin; DeuelFrom 05:00Z · until 14:00Z · NWS Aberdeen SD · drawn over this area
Freeze WarningWilkin; West Otter Tail; East Otter Tail; Wadena; GrantFrom 05:00Z · until 14:00Z · NWS Grand Forks ND · drawn over this area
Frost AdvisoryBrown; Marshall; Roberts; Day; Spink; ClarkFrom 05:00Z · until 14:00Z · NWS Aberdeen SD · drawn over this area

Most urgent first, by the Briefing’s ranking. Checked 03:07Z.

Spotlight: Winter Storm Severity Index

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Winter Storm Severity Index

WPC: “WSSI does not depict official warnings and should always be used in context with official NWS forecasts and warnings.”

Winter Weather Area
Minor Impacts
Moderate Impacts
Major Impacts
Extreme Impacts

Highest in this area, by day and by cause

Day 1: nothing drawn
Day 2: nothing drawn
Day 3: nothing drawn
Snow amount, Days 1–3: nothing drawn
Snow load, Days 1–3: nothing drawn
Ice, Days 1–3: nothing drawn
Blowing snow, Days 1–3: nothing drawn

Each day and cause on the Winter tab, with its own issue time

WPC’s WSSI, overall impact, Days 1–3, valid 00:00Z to 20 Oct 00:00Z, issued 00:14Z. WPC issues each day and cause on its own clock. Not a warning, and not a chance. Data: NOAA/NWS/WPC.

Chance of Moderate impacts or worse, Day 1

WPC: “WSSI does not depict official warnings and should always be used in context with official NWS forecasts and warnings.”

5–10%
10–20% (not drawn)
20–30% (not drawn)
30–40% (not drawn)
40–50% (not drawn)
50–60% (not drawn)
60–70% (not drawn)
70–80% (not drawn)
80–90% (not drawn)
90–95% (not drawn)
95% or more (not drawn)

Each level and day on the Winter tab

WPC’s WSSI-P, the 24 hours 00:00Z to 18 Oct 00:00Z, WPC’s forecast from 00:00Z. Each band runs to the next. Data: NOAA/NWS/WPC.

Chance of at least 4 inches of snow, Day 1

WPC gives no chance of 4 inches of snow or more in this area over the next three days, so Day 1’s 4 inches is shown.

Slight: at least 10%
Moderate: at least 40%
High: at least 70%

Every day and amount on the Winter tab

WPC’s Probabilistic Winter Precipitation Forecast, 00:00Z to 18 Oct 00:00Z, issued 16 Oct 19:54Z. Outlines, as WPC draws them. Data: NOAA/NWS/WPC.

Winter watches, warnings and advisories

Freeze Warning 2 2 not yet in effect · until 14:00Z · NWS Aberdeen SD, NWS Grand Forks ND
Frost Advisory 1 1 not yet in effect · until 14:00Z · NWS Aberdeen SD

NWS’s winter and cold alerts in force in the area, by event as issued, each counted once, with the offices that issued them and the latest end. Data: NOAA/NWS.

Snow on the ground

NOHRSC snow depth and snow water equivalent use the source’s original pictures and legends, with qualified footprint times. Open the cached source page for availability and retained history. This wall has no snow picture to rotate; missing imagery does not mean no snow.

NOHRSC snow analysis and retained pictures

Data: NOAA/NWS/NOHRSC. Snow analysis, not a measurement at a place.

WPC’s heavy snow and icing discussion

The whole discussion

Issued 16 Oct 18:07Z, for 00:00Z to 20 Oct 00:00Z. WPC’s words, as written. Data: NOAA/NWS/WPC.

SPC Day 1 outlook

General Thunderstorms Risk

SPC’s Day 1 categorical outlook, valid 01:00Z to 12:00Z, issued 00:50Z. SPC’s categories, as drawn. Data: NOAA/SPC.

Watches

No tornado or severe thunderstorm watch in force in this area.

SPC’s watches, by number, matched by the counties they list. Data: NOAA/SPC.

Mesoscale discussions

No mesoscale discussion reaches this area.

SPC’s mesoscale discussions whose outline reaches the area. Data: NOAA/SPC.

Storm ingredients

SPC’s hourly mesoanalysis, observed soundings and model guidance for the area, on the Analysis tab with its own clocks.

Open the Analysis tab

Drawn by the Analysis tab’s own renderer. Data: NOAA/SPC, NOAA/NCEP.

Flash-flood risk, Day 1

Marginal

WPC’s excessive rainfall outlook, 01:00Z to 12:00Z, issued 00:56Z: a chance of flash flooding, in four categories. Data: NOAA/WPC.

River gauges in flood

2 major · 0 moderate · 0 minor · 0 at action stage

major Devils Lake DCBN8, observed
major Lakota ESLN8, observed

NWS’s gauges at flood stage or above in the area, worst first, each with its forecast hydrograph on Rain & rivers. Data: NOAA/NWPS.

Rain expected and rain that fell

WPC’s rain forecast and MRMS’s radar estimate of the rain that fell, on the Briefing’s map for the area.

Open Rain & rivers

Data: NOAA/WPC, NOAA/NSSL MRMS.

The tropics

NHC’s and JTWC’s storms, their official graphics and the watches and warnings for them. Storm Mode’s own tropical panels arrive with its tropical events.

Open the Tropics page

Data: NOAA/NHC, JTWC.

Radar, winter preset

The Radar page’s winter preset over the area: HRDPS forecast snow with NWS’s warnings on top, loaded by your browser. A forecast, labelled as one there.

Open the radar

Live tiles; the radar keeps no last-good copy.

What changed, last 60 minutes

02:15ZWPC Winter Storm Severity Index issued

The products’ own words and times, and what is no longer in force since the last read. Never written by AI.