Colorado Hail Storm Report, June 30, 2026: Radar Estimated Hail Over 2.75 Inches Along the South Platte Near Iliff and Crook

On the evening of June 30, 2026, a tornado-warned storm ran down the South Platte valley northeast of Sterling with radar-estimated hail cores above 2.75 inches — the estimated 2.00 inch contour sat directly over Proctor — while the largest hail anyone reported on the ground was 1.25 inches. That gap is the story of this report.

The Iliff and Crook hail map — June 30, 2026

What was reported on the ground

These are the only hail reports on the corridor that evening. Measured means an observer put a ruler or gauge on the stone; reported means a size category was selected. Times are MDT.

What radar estimated over the corridor

All figures below are radar estimates — MRMS output, not measurements. The convective-day analysis puts about 687 square miles of Colorado under estimated 1.00 inch or larger hail that day, with 96 square miles under estimated 2.00 inch or larger and about 16 square miles under estimated 2.75 inch or larger — nearly all of it in one swath train along the South Platte from northwest of Sterling through Iliff and Proctor toward Crook.

• Proctor sits inside the estimated 2.00 inch contour, six-tenths of a mile from the estimated 2.50 inch core.
• Iliff sits inside the estimated 1.00 inch swath, a mile from the 1.75 inch contour and under two miles from an estimated 2.75 inch core.
• Crook sits inside the estimated 1.00 inch swath, seven-tenths of a mile from the 1.50 inch contour.
• Sterling sat just outside the swath — about a mile from the 1.00 inch contour, four to six miles from the big cores.

Why the gap between radar and reports

A hail report only exists when someone finds the stones and files a report. This storm crossed sparsely populated river-bottom ranchland at dusk, under a tornado warning — the three reports that exist were filed from the couple of roads with people on them, while the estimated cores tracked the empty ground between. The absence of further reports is not evidence that hail did not fall.

The honest cut goes both ways: radar hail output is a deliberate high-end estimate of what may exist inside the storm, and it can overestimate what actually lands. Never treat an estimated 2.75 inch core as proof that 2.75 inch hail fell near Iliff — and never treat three small reports as proof that it did not. Treat the swath as the search area; a physical inspection is the only thing that settles a specific address.

The storm was warned, start to finish

A severe thunderstorm warning covered the corridor from 6:51 PM — 54 minutes before the first hail report — followed by warnings at 7:32 and 8:10 PM, a tornado warning from 7:49 to 8:24 PM covering the 8:16 PM Crook hail, and a second tornado warning from 8:22 to 8:38 PM. Two tornadoes were reported, east of North Sterling Reservoir at 7:40 PM and east of Sterling at 7:46 PM. A personal weather station near Iliff recorded a 74 mph gust at 7:54 PM.

Frequently asked questions

This is the second radar-only case of the season — the first was July 29 over the Bennett and Strasburg corridor. Red Hawk tracks every significant hail day across Colorado — see the 2026 season archive. Before any adjuster visit, read what hail damage actually looks like on a roof and the Colorado hail claim guide, or see our hail damage service for what an inspection covers.

Storm figures are National Weather Service Local Storm Reports for Colorado on June 30, 2026, retrieved from the Iowa Environmental Mesonet archive; warning times are from the NWS watch/warning archive. Times are MDT and reports are grouped by the local calendar day. Radar swath analysis by ExoVzn, an independent forensic meteorology firm, using NOAA MRMS data. All radar figures are estimates. Storm reports and radar analysis indicate where hail may have occurred; only a physical inspection establishes whether a specific roof or structure was damaged.