STORMVAULT

Weather Intelligence Archive

Ready

Date & Time Range (UTC)

SuMoTuWeThFrSa

Time Window What's this?

Time Window Conventions

The IEM API always queries in UTC. Each preset below decides how your selected date(s) map to a UTC range.

Convective Day (12Z–12Z UTC) — SPC standard "severe weather day." Picking Apr 26 fetches Apr 26 12:00Z → Apr 27 12:00Z. Captures the afternoon-through-overnight severe window. Best default for chase day analysis.

Calendar Day (00Z–24Z UTC) — Pure UTC midnight-to-midnight. Picking Apr 26 fetches Apr 26 00:00Z → Apr 26 23:59Z. Note: this is the UTC date, not your local date. A warning issued at 11 PM ET on Apr 25 will appear here under "Apr 26" because UTC has already rolled over.

Custom (Local ET) — Enter Eastern Time start/end for the picked date. The system converts to UTC and rolls the end date forward across midnight automatically. Picking Apr 26, 12:00 AM → 11:59 PM ET fetches Apr 26 04:00Z → Apr 27 03:59Z (during EDT). DST is handled automatically.

Warning Types to Fetch

Storm Reports What's the difference?

IEM LSR vs SPC Reports

IEM LSR — Raw Local Storm Reports from NWS offices. Real-time. May include duplicates (multiple reports per event from spotters, radar, surveys). Best for same-day events.

SPC Filtered — Post-processed by SPC staff. De-duplicated, one entry per event. Best for clean counts and historical analysis. Typically available next day.

SPC Unfiltered — All raw reports archived by SPC. Same as IEM LSR but from SPC's archive. Useful when IEM LSR isn't available.

Tip: Use IEM LSR for live events, SPC Filtered for next-day and historical review.

Tornado Hail Wind

Colors: Torn Hail Wind

Sources to Fetch

▶ Filter Reports

State

Type

Rating

SPC Outlooks

What's this?

Day 1 categorical outlook for each day in date range. Toggle categories in Layers panel.

Cycle:

Opacity40%

▶ Custom Mapping

Basemap

Ocean / Background

Land Fill

State Boundaries

Line Color

Weight3.0

Style

County Boundaries

Show Counties

Line Color

Opacity100%

Show County Names

City & Town Labels

Show Labels

Location Dot

Size20px

Font Color

Text Edge

Pill Background

Pill Opacity90%

▶ Warning Style

Fill40%

Stroke1.0

Outline0.8

Outline color

Polygon Glow

Custom Load Files

📦 IEM Warning .ZIP

📄 SPC Report .CSV

Summary

Tornado

Emergency—

PDS—

Confirmed—

Radar Indicated—

Severe Thunderstorm

Destructive—

Considerable—

Standard—

Flash Flood

Emergency—

Catastrophic—

Considerable—

Standard—

Marine—

Storm Reports

Tornado Rpts—

Sig (EF2+)—

Hail Rpts—

Sig (2"+)—

Wind Rpts—

Sig (65kt+)—

SPC Outlooks

Days Loaded—

HIGH—

MDT—

ENH—

SLGT—

MRGL—

TSTM—