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SPC daily storm reports, explained

The Storm Prediction Center publishes raw local storm reports for each "convective day" — a 1200 UTC to 1200 UTC window, which is why a 1 a.m. storm files under the previous day's date. Times are UTC; hail sizes are recorded in hundredths of an inch (150 = 1.50"); wind entries may carry "UNK" when a gust was reported without a speed. Reports are amended for several days as offices correct relays.

These rows are the news-cycle view — on file the morning after a storm, months before NCEI compiles the official entry. Used correctly (labeled preliminary, superseded by Storm Events when compiled), they are what makes same-week claim documentation possible at all.

Why does the SPC date differ from the local storm date?

Convective days run 1200 UTC to 1200 UTC. A storm at 1 a.m. Central on June 13 files under the June 12 convective day. Our pages and reports convert and label this so a date-of-loss argument never trips on it.

How fast do SPC reports appear?

Typically within hours — the page populates live during an event. We ingest each completed convective day the following morning, then re-fetch several prior days because amendments are routine.

Are SPC reports usable in a claim?

Yes, labeled as what they are: preliminary official relays, appropriate for recent dates the compiled record has not reached. Once the Storm Events entry exists, cite that instead.

Sources and standing caveat

Official records referenced throughout: NCEI Storm Events Database (the official NWS storm record, 1950–present) and SPC daily storm reports (preliminary, same-day). NWS records are point and path observations. The absence of a nearby report does NOT prove that no hail fell at this address — it means no observation was logged nearby. A report of nearby hail documents the event; it does not by itself prove damage to a specific structure. Nothing on this page is legal, insurance, or public-adjusting advice — deadlines, coverage and remedies are policy- and state-specific.

Put the record in the file

A per-address verification report compiles every NWS-recorded hail and wind event within 1, 3 and 10 miles of any US address — distances, official narratives, citations, provenance labels — formatted as an insurance-appeal attachment, hosted on HailEvidence (the neutral evidence surface).

Unlimited reports — Pro $99/mo Single report $29