Flood in Wyoming, May 24 to 30, 2015

Name: Flood in Wyoming, May 24 to 30, 2015
Start: 2015-05-24T12:00
End: 2015-05-30T12:00
Location: Wyoming

May 24 to 30, 2015 · NWS BYZ · 1 event in 1 county or zone

Heavy rains combined with snow melt out of the Big Horn Mountains brought flooding to portions of Sheridan.

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

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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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 BYZ wrote it up.

Heavy rains combined with snow melt out of the Big Horn Mountains brought flooding to portions of Sheridan.

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 Billings, MT wrote its last area forecast discussion before the first event at May 24, 8:29 AM MST, 3 hours 31 minutes earlier.

Area forecast discussion, May 24, 8:29 AM MST, 3 hours 31 minutes before

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BILLINGS MT
929 AM MDT SUN MAY 24 2015

.UPDATE...

WE UPDATED THE FORECAST TO REFLECT THE LATEST RADAR TRENDS AND RAP
SIMULATIONS...WHICH MAINLY MEANT INCREASING POPS TO 100 PERCENT IN
THE SHERIDAN AREA THROUGH THE DAY WHERE MODERATE RAIN IS OCCURRING
ALREADY THIS MORNING. SHOWERS WILL FILL IN OVER FAR SOUTHEASTERN
MT BY AFTERNOON TOO AS FORCING ALOFT SHIFTS NORTHWEST OUT OF SD.
THE SHOWERS WILL BE MORE OCCASIONAL OR SCATTERED IN NATURE FURTHER
TO THE NORTHWEST LIKE IN BILLINGS TODAY...ESPECIALLY BY AFTERNOON.

OTHERWISE...WE DID LOWER FORECAST HIGHS A BIT IN SPOTS WHERE CLOUD
COVER AND SHOWER COVERAGE WILL BE GREATEST TODAY. SCHULTZ

&&

.SHORT TERM...VALID FOR TDY AND MON...

AN UPPER LOW HAS MOVED INTO NORTHERN COLORADO ON ITS SLOW AND
STEADY PROGRESSION INTO THE CENTRAL PLAINS. POSITION OF THIS LOW
HAS KEPT EAST TO NORTHEAST WINDS OVER THE FORECAST AREA. THIS WAS
TRANSPORTING HIGHER DEWPOINT AIR INTO MONTANA WITH DEWPOINTS
CLIMBING INTO THE 50S NOW OVER WESTERN SOUTH DAKOTA. PRECIPITABLE
WATER VALUES HAVE RISEN TO OVER THREE QUARTERS OF AN INCH OVER
MOST OF THE STATE. THIS WILL LEAD TO EASY CLOUD COVER THE NEXT TWO
DAYS AND KEEP TEMPERATURES DOWN. BREAKS IN THE CLOUDS SHOULD
QUICKLY FILL BACK IN TODAY. THE COLORADO LOW WILL WORK INTO
SOUTHEAST WYOMING THIS AFTERNOON AND WRAP ENERGY AROUND INTO
MONTANA. INSTABILITY WAS NOT GREAT...BUT WITH HIGH PWATS...THERE
WILL BE QUITE A FEW SHOWERS AROUND. WEAK STEERING WINDS WILL KEEP
THUNDERSTORMS TO A MINIMUM BUT ALSO PROVIDE FOR LOCALLY HEAVY
RAINS IN THE SHOWERS THAT FORM. HIGHEST POPS WILL BE OVER THE
EASTERN HALF OF THE AREA...AS MODELS HAVE BEEN CONSISTENTLY
POINTING TO THIS AREA FOR HIGHEST QPF.

THE LOW FILLS AND SLIDES INTO THE MIDWEST ON MEMORIAL DAY. IT HAD
BEEN LOOKING LIKE A RIDGE WOULD SLIDE INTO SOUTHERN MONTANA AND
NORTHERN WYOMING ON MONDAY...BUT A SLOWER MOVEMENT OF THE SOUTHERN
LOW HAS TAKEN THAT SOLUTION OUT OF THE PICTURE. LINGERING ENERGY
AND MOISTURE WITH UPSLOPE FLOW WILL LEAD TO MORE SCATTERED SHOWERS
AROUND THROUGH THE DAY...ALTHOUGH NOT QUITE AS NUMEROUS AS TODAY.
LOCALLY HEAVY RAIN WILL AGAIN BE A POSSIBILITY WITH SLOW MOVING
CELLS AND PWATS OVER THREE QUARTERS OF AN INCH. HAVE COOLED HIGH
TEMPERATURES DOWN A COUPLE OF DEGREES FOR MONDAY DAY AS EXPECTING
LINGERING CLOUD COVER. TWH

.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...

THE LONG TERM CONTINUES TO BE VERY CONSTANT. A LOW OVER THE
PACIFIC NORTHWEST CONTINUES TO DOMINATE MUCH OF THE WEATHER FOR
THE WEEK. THE LOW WILL PLACE THE AREA IN UNSETTLED...SOUTHWEST
FLOW ALLOWING SEVERAL IMPULSES OF ENERGY TO MOVE ACROSS THE AREA.
GIVING THE AREA A CHANCES FOR RAIN EACH AFTERNOON. AS THE LOW
BEGINS TO MOVE EAST THURSDAY...A COLD FRONT WILL MOVE ACROSS
MONTANA. THIS WILL ENHANCE RAIN CHANCES A LITTLE AND BRING COOLER
TEMPERATURES. GOING INTO NEXT WEEKEND THE PATTERN BEGINS TO SHIFT
AS A RIDGE STARTS BUILDING IN BEHIND THE DEPARTING TROUGH...WHICH
WILL SEE RAIN CHANCES BEGIN TO DECREASE. TEMPERATURES WILL BE NEAR
NORMAL THROUGH MUCH OF THE EXTENDED EXCEPT FOR THE BRIEF COOL
DOWN WITH THE COLD FRONT THURSDAY AND FRIDAY. REIMER

&&

.AVIATION...

SCATTERED SHOWER ARE POSSIBLE THROUGH MUCH OF THE DAY. AROUND THE
MOUNTAINS SHOWERS WILL BE MORE NUMEROUS. MVFR TO IFR CONDITIONS
WILL PERSIST THIS MORNING...AND MVFR CONDITIONS ARE LIKELY THROUGH
THE DAY ESPECIALLY IN SHOWER ACTIVITY. MOUNTAIN OBSCURATIONS WILL
CONTINUE THROUGH THE DAY. REIMER

&&

.PRELIMINARY POINT TEMP/POPS...

    TDY MON     TUE     WED     THU     FRI     SAT
-------------------------------------------------------
BIL 060 045/068 049/072 049/071 049/068 047/067 047/071
    6/T 42/T    23/T    33/T    33/T    33/T    32/T
LVM 059 039/070 045/068 044/066 043/066 043/067 042/069
    5/T 43/T    36/T    54/T    44/T    43/T    33/T
HDN 062 045/069 046/075 049/074 048/070 047/069 045/072
    6/T 43/T    23/T    33/T    33/T    33/T    32/T
MLS 064 047/068 048/075 051/074 050/070 048/068 046/069
    7/T 54/T    22/T    33/T    33/T    32/T    22/T
4BQ 058 046/066 044/073 049/073 049/069 048/066 046/067
    +/T 64/T    22/T    34/T    33/T    33/T    32/T
BHK 061 045/066 046/071 047/070 048/068 044/064 042/065
    6/T 75/T    32/T    34/T    44/T    33/T    32/T
SHR 054 043/064 044/070 045/069 045/066 044/065 042/067
    +/T 64/T    23/T    33/T    33/T    33/T    33/T

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.

&&

WEATHER.GOV/BILLINGS

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 flood. Local standard time, as filed.

Flood, Sheridan

When: May 24, 12:00 PM MST to May 30, 12:00 PM MST
Where: Sheridan County, 3.07 mi SSE of (Shr)sheridan Co Arp to 0.79 mi SSE of Sheridan
Cause: Heavy Rain / Snow Melt
Reported by: Emergency Manager
Coordinates: 44.732, -106.948

Heavy rains combined with snow melt out of the Big Horn Mountains brought flooding to portions of Sheridan. Little Goose Creek reached moderate flooding levels. Two subdivisions south of Sheridan were hit hard. Woodland Hills experienced water, up to about two feet deep, running over the road. Just to the north, water at Woodland Park Village reached about 8 feet at the bridge. Volunteers pulled debris out of water to prevent the bridge from washing out. In Sheridan proper, South Park was almost completely underwater, as was a portion of the field directly south of Brundage. There were also reports of flooding along Big Goose Creek above Kendrick Park. In addition, Mavrakis Pond near 8th in Sheridan flowed over its banks on the east side.

What these are

Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

Every storm in Wyoming in 2015 Every state in 2015 This day in weather history Warnings in Wyoming, May 2015

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: 585729.