Flash Flooding and Hail in Nebraska, August 18, 2016

Name: Flash Flooding and Hail in Nebraska, August 18, 2016
Start: 2016-08-18T16:57
End: 2016-08-18T20:45
Location: Nebraska

August 18, 2016 · NWS CYS · 9 events in 3 counties and zones

Thunderstorms produced large hail and very heavy rainfall across portions of the southern Nebraska Panhandle. Flash flooding was reported in Banner, Morrill and Kimball counties.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 9

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS CYS wrote it up.

Thunderstorms produced large hail and very heavy rainfall across portions of the southern Nebraska Panhandle. Flash flooding was reported in Banner, Morrill and Kimball counties.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before the first event at Aug 18, 4:49 PM MST, 8 minutes earlier.

Area forecast discussion, Aug 18, 4:49 PM MST, 8 minutes before

Area Forecast Discussion
National Weather Service Cheyenne WY
549 PM MDT THU AUG 18 2016

.SHORT TERM...(This evening through Saturday)
Issued at 235 PM MDT Thu Aug 18 2016

The main concern with this portion of the forecast is how
widespread precipitation chances will be during the next 24 hrs
and how cold it will get on Saturday morning.

Tonight:
Latest radar loop was showing numerous showers and thunderstorms
developing within a broad scale upper level diffluence zone.
Latest MSAS/obs data was also showing some good low level
convergence mainly along and southeast of the Laramie Range. Weak
frontal boundary has now surged through Torrington and Wheatland
and areas north of Alliance. Temperatures have continued to
gradually drop behind this boundary. This boundary should surge
through the remainder of the forecast area this evening. Could
still see a few strong storms this evening with small hail and
gusty winds. Another concern is the heavy rain potential due to
slow movement of these storms. This shower and thunderstorm
activity should begin to weaken after sunset, but we may also see
some stratus develop due to the low level moisture increasing
behind the boundary.

Friday-Saturday:
Latest water vapor loop was showing a fairly strong shortwave
moving into northwest Montana. This looks to be the leading edge
of our surge of much colder air. Based on water vapor trends, this
feature may reach the northern half of our forecast area by
daybreak. This is faster than what the latest nam is suggesting.
We will have to keep an eye on this during the night. If this
boundary does moves through quicker we may see temperatures drop
quicker than expected during the day tomorrow with a really good
chance of rain following behind it. Temperatures may try to
recover during the late afternoon mainly in the northern half of
the area, but it will be a chilly day overall. High pressure then
builds south into the area friday night into Saturday morning.
This should bring much colder temperatures with overnight lows
possibly dropping near freezing in Laramie with mostly 30s to
around 40 elsewhere. In fact, this could be near record lows for
this time of year. Later shifts may need to issue and Frost
Advisory for the Laramie valley tomorrow night. After a cool start
Saturday should be a cool but a mostly sunny day.

.LONG TERM...(Saturday night through Thursday)
Issued at 235 PM MDT Thu Aug 18 2016

A seasonally benign period upcoming for the latter half of the
weekend and into early next week. Dry northwest flow over the CWFA
Saturday night will be replaced by a transitory ridge for Sunday and
Sunday Night. This will yield generally dry conditions Sunday and
Monday with temperatures warming back to seasonal normals on Sunday
and above normals for Monday. In fact high temperatures will warm
back into the 80s above 4000 feet, with 90s below on Monday. Monday
will need to be watched for the possibility of red flag conditions
in areas west of the Laramie Range. By Tuesday, both the ECMWF/GFS
advertise weak shortwave energy lifting northeast thru the CWFA
which will likely enhance convective chances in mountain locations.
Afternoon/evening thunderstorm chances will continue Tue-Thu as a
series of impulses rotate thru cyclonic flow around a stalled area
of low pressure located across southern Canada. High temperatures
will fall back into the 70s Wed-Thu as cooler air is advected into
the region.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 547 PM MDT Thu Aug 18 2016

Cold front moving into the area late this afternoon/evening will
bring northeast upsloping winds and increasing chances for
MVFR/IFR ceilings. Used latest HRRR forecast which has timing on
lower ceilings around 06Z or shortly thereafter. Lower ceilings
will last through the overnight hours into Friday morning before
lifting.

&&

.FIRE WEATHER...
Issued at 235 PM MDT Thu Aug 18 2016

Numerous showers and thunderstorms will tend to suppress critical
fire weather conditions during the next couple of days. May see
an occasional lightning from some of the convection this evening
which may start a fire or two. Otherwise, the next critical fire
weather conditions appear to develop early next week.

&&

.CYS Watches/Warnings/Advisories...
WY...None.
NE...None.
&&

SHORT TERM...REC
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...REC

Hazardous weather outlook, Aug 18, 4:47 AM MST, 12 hours 10 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
547 AM MDT THU AUG 18 2016

NEZ002-003-019>021-054-055-095-096-WYZ101>108-117>119-191200-
DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE-
NORTH SIOUX-SOUTH SIOUX-CONVERSE COUNTY LOWER ELEVATIONS-
NIOBRARA COUNTY-NORTH LARAMIE RANGE-
FERRIS/SEMINOE/SHIRLEY MOUNTAINS-SHIRLEY BASIN-
CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY-
EAST PLATTE COUNTY-GOSHEN COUNTY-SOUTH LARAMIE RANGE FOOTHILLS-
CENTRAL LARAMIE COUNTY-EAST LARAMIE COUNTY-
547 AM MDT THU AUG 18 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN
NEBRASKA AND SOUTHEAST WYOMING.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS WILL DEVELOP AHEAD OF A STRONG COLD
FRONT LATE THIS MORNING. SOME OF THESE THUNDERSTORMS MAY BECOME
STRONG TO MARGINALLY SEVERE THIS AFTERNOON AND THIS EVENING.
STRONG GUSTY WINDS AND HAIL ARE POSSIBLE WITH THE STRONGEST
STORMS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS WILL CONTINUE FRIDAY AND FRIDAY NIGHT. SOME STRONG
THUNDERSTORMS ARE POSSIBLE NEAR THE COLORADO BORDER.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE REQUIRED.

WYZ109>116-191200-
CENTRAL CARBON COUNTY-NORTH SNOWY RANGE FOOTHILLS-
SOUTHWEST CARBON COUNTY-SIERRA MADRE RANGE-
UPPER NORTH PLATTE RIVER BASIN-SNOWY RANGE-LARAMIE VALLEY-
SOUTH LARAMIE RANGE-
547 AM MDT THU AUG 18 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
WYOMING AND SOUTHEAST WYOMING.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS WILL DEVELOP AHEAD OF A STRONG COLD
FRONT THIS AFTERNOON. SEVERE THUNDERSTORMS ARE NOT EXPECTED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE REQUIRED.

In the hours before

Local storm report, Aug 18, 12:31 PM MST, 4 hours 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
131 PM MDT THU AUG 18 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 PM     HAIL             10 S LUSK               42.62N 104.45W
08/11/2016  E1.00 INCH       NIOBRARA           WY   PUBLIC

&&

RCOX

Special weather statement, Aug 18, 4:18 PM MST, 39 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
518 PM MDT THU AUG 18 2016

NEZ021-182345-
MORRILL NE-
518 PM MDT THU AUG 18 2016

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN MORRILL COUNTY UNTIL
545 PM MDT...

AT 518 PM MDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
THE INTERSECTION OF HIGHWAY 385 AND 92...OR 32 MILES NORTHWEST OF
OSHKOSH...MOVING WEST AT 10 MPH.

NICKEL SIZE HAIL AND WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH
THIS STORM.

LOCATIONS IMPACTED INCLUDE...
BRIDGEPORT...THE INTERSECTION OF HIGHWAY 385 AND 92 AND BROADWATER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD TO
LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 10 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO
STATIONS AND AVAILABLE TELEVISION STATIONS FOR ADDITIONAL INFORMATION
AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4169 10284 4157 10280 4150 10307 4166 10314
TIME...MOT...LOC 2318Z 079DEG 8KT 4161 10292

MAZUR

Local storm report, Aug 18, 4:23 PM MST, 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
523 PM MDT THU AUG 18 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0521 PM     HAIL             3 NW BROADWATER         41.63N 102.89W
08/18/2016  E0.25 INCH       MORRILL            NE   TRAINED SPOTTER

            HEAVY RAIN WITH WINDS OF AROUND 25 TO 30 MPH.

&&

BCHAPMAN

The radar

The Cheyenne radar (KCYS), 153 km away, was scanning. The volume nearest the first event began at 23:56 UTC.

Open the radar archive at this moment

Event by event

3 hail, 3 heavy rain, 3 flash flood. Local standard time, as filed.

Hail, Morrill

When: August 18, 4:57 PM MST to 5:00 PM MST
Where: Morrill County, Bridgeport
Measured: 1 in hail
Reported by: Public
Coordinates: 41.670, -103.100

Quarter size hail damaged a trailer and house in Bridgeport.

Hail, Morrill

When: August 18, 5:00 PM MST to 5:08 PM MST
Where: Morrill County, Bridgeport
Measured: 1.75 in hail
Reported by: Law Enforcement
Coordinates: 41.670, -103.100

Quarter to golf ball size hail was reported at Bridgeport.

Heavy Rain, Kimball

When: August 18, 5:00 PM MST to 6:25 PM MST
Where: Kimball County, Bushnell
Reported by: Emergency Manager
Coordinates: 41.230, -103.890

Two and a half inches of rain was reported at Bushnell.

Hail, Morrill

When: August 18, 5:04 PM MST to 5:08 PM MST
Where: Morrill County, 1 mi W of Bridgeport
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 41.670, -103.119

Ping pong ball size hail was reported a mile west of Bridgeport.

Flash Flood, Kimball

When: August 18, 5:40 PM MST to 7:40 PM MST
Where: Kimball County, 1.76 mi NW of Bushnell to 2.67 mi SW of Bushnell
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 41.245, -103.918

Flash flooding was reported at Bushnell, Kimball and Dix.

Heavy Rain, Banner

When: August 18, 6:00 PM MST to 7:15 PM MST
Where: Banner County, 15.24 mi E of Harrisburg
Reported by: Public
Coordinates: 41.590, -103.450

Nearly one and three-quarters of an inch of rain was reported eight miles west of Redington.

Flash Flood, Banner

When: August 18, 6:56 PM MST to 8:00 PM MST
Where: Banner County, 15.24 mi E of Harrisburg to 16.89 mi E of Harrisburg
Cause: Heavy Rain
Reported by: Public
Coordinates: 41.590, -103.450

Flash flooding was reported eight miles west of Redington. Corrals were flooded with widespread standing water.

Heavy Rain, Morrill

When: August 18, 7:00 PM MST to 8:20 PM MST
Where: Morrill County, Bayard
Reported by: Public
Coordinates: 41.760, -103.320

Two inches of rain was reported at Bayard.

Flash Flood, Morrill

When: August 18, 8:20 PM MST to 8:45 PM MST
Where: Morrill County, 0.86 mi NW of Bayard to 0.94 mi N of Bayard
Cause: Heavy Rain
Reported by: Public
Coordinates: 41.768, -103.333

Many low lying areas were flooded at Bayard.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Nebraska in 2016 Every state in 2016 This day in weather history Warnings in Nebraska, August 2016

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 644207, 644209, 644212, 644210, 644211, 644213, 644215, 644216, 644217.