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Flood Warning

Flood Statement
National Weather Service Great Falls MT
816 PM MDT SUN MAY 20 2018

Madison MT-Beaverhead MT-
816 PM MDT SUN MAY 20 2018


* Water levels on the Big Hole River continue to rise due to ongoing
  snowmelt. Additional rises will occur this week as temperatures
  warm into the 50s in the mountains and the remaining snowpack
  melts. Thunderstorms, some of which could produce locally heavy
  rainfall, are also expected daily this week.

* Water levels could rise further than what is currently forecasted
  should significant rainfall from thunderstorms occur within the Big
  Hole River Basin. If you live near the Big Hole River, we urge you
  to be prepared to action should floodwaters threaten.

* Point forecast for the Big Hole River near Melrose.
    * At 7:15 PM Sunday the stage was 6.3 feet.
    * Flood stage is 6.0 feet.
    * Moderate flooding is forecast.
    * Forecast...Continue to rise to near 7.8 feet by Thursday night.
    * Impacts...At 6.2 feet, water starts to affect areas near Glen.
      At 7 feet, agricultural land floods and irrigation systems
      need to be protected.

* Some locations that may experience flooding include...
  Wisdom, Melrose, Wise River, Dewey and Glen.


Turn around, don`t drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Excessive runoff from snowmelt may cause flooding of small creeks
and streams, country roads, farmland, and other low lying spots.

Please report flooding to your local law enforcement agency when you
can do so safely.


LAT...LON 4578 11341 4575 11336 4580 11335 4587 11322
      4588 11312 4581 11300 4576 11277 4563 11270
      4565 11263 4550 11259 4564 11239 4546 11235
      4538 11271 4568 11281 4579 11319 4559 11340
      4560 11357



Flood Watch

Flood Watch
National Weather Service Great Falls MT
1151 AM MDT Sun May 20 2018

1151 AM MDT Sun May 20 2018


The National Weather Service in Great Falls has issued a
* Flood Watch
  for the Jefferson River near Three Forks
* from late Monday night until further notice.
* At 11:00 AM Sunday the stage was 7.8 feet.
* Flood stage is 8.0 feet.
* Major flooding is possible.
* Forecast...Flood stage may be reached late Monday night.
* Impacts...At 8.0 buildings flood around Three
  Forks. At 8.5 feet...county roads and bridges may have water
  flowing over them. Several homes could flood.


A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

The latest stages and forecasts for rivers and streams can be found
at our web



Hazardous Weather Outlook

Hazardous Weather Outlook...UPDATED
National Weather Service Cheyenne WY
244 PM MDT Sun May 20 2018

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-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-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
244 PM MDT Sun May 20 2018

This hazardous weather outlook is for portions of east central
Wyoming...south central Wyoming and southeast Wyoming.


A few thunderstorms will be possible this afternoon and evening near
the Sierra Madre and Snowy Mountain Ranges. No severe weather is
expected with this activity.


We will see an increase in thunderstorm chances Tuesday and
Wednesday across southeastern Wyoming. A few severe thunderstorms
will be possible for areas along and east of the Laramie Mountain

.Spotter information statement...

Spotter activation will not be needed through Monday.


Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1115 AM MDT Sun May 20 2018

Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1115 AM MDT Sun May 20 2018

This hazardous weather outlook is for northeast and north central

.DAY ONE...Today and Tonight

The drizzle and fog has ended across the forecast area late this
morning. Scattered showers and thunderstorms will form over the
mountains this afternoon. These storms may move onto the foothills
and nearby plains before dissipating early this evening. Small
hail and brief heavy rain will be possible with the stronger

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Drier and warmer weather will continue through the upcoming week
except for a chance of afternoon and evening thunderstorms each
day, especially over the higher terrain.


Spotter activation will not be needed today.


Hazardous Weather Outlook
National Weather Service Salt Lake City UT
922 AM MDT Sun May 20 2018

Cache Valley/Utah Portion-Northern Wasatch Front-
Salt Lake and Tooele Valleys-Southern Wasatch Front-
Great Salt Lake Desert and Mountains-Wasatch Mountain Valleys-
Wasatch Mountains I-80 North-Wasatch Mountains South of I-80-
Western Uinta Mountains-Wasatch Plateau/Book Cliffs-
Western Uinta Basin-Castle Country-San Rafael Swell-
Sanpete/Sevier Valleys-West Central Utah-Southwest Utah-
Utahs Dixie and Zion National Park-South Central Utah-
Glen Canyon Recreation Area/Lake Powell-Central Mountains-
Southern Mountains-Southwest Wyoming-
922 AM MDT Sun May 20 2018

This Hazardous Weather Outlook is for the western two thirds of
Utah and southwest Wyoming.

.DAY ONE...Today and Tonight

Thunderstorms are expected to develop this afternoon across
much of the area. The strongest storms will be capable of brief,
gusty winds and small hail.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

No hazardous weather is expected.


Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.


For more information from NOAA/s National Weather Service visit...

For information on potential road travel impacts visit...

Hazardous Weather Outlook
National Weather Service Grand Junction CO
546 AM MDT Sun May 20 2018

Lower Yampa River Basin-Central Yampa River Basin-
Roan and Tavaputs Plateaus-Elkhead and Park Mountains-
Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor-
Central Colorado River Basin-Grand and Battlement Mesas-
Gore and Elk Mountains/Central Mountain Valleys-
Central Gunnison and Uncompahgre River Basin-
West Elk and Sawatch Mountains-Flat Tops-
Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide-
Northwest San Juan Mountains-Southwest San Juan Mountains-
Paradox Valley/Lower Dolores River-
Four Corners/Upper Dolores River-Animas River Basin-
San Juan River Basin-Southeast Utah-Eastern Uinta Mountains-
Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat-
La Sal and Abajo Mountains-Canyonlands/Natural Bridges-
546 AM MDT Sun May 20 2018

This hazardous weather outlook is for eastern Utah and western

.DAY ONE...Today and Tonight

A weak disturbance will move overhead today bringing some showers
and storms to areas south of I-70 before shifting northward
through the afternoon. Most convection will die down shortly after

.DAYS TWO THROUGH SEVEN...Monday through Saturday

A trough to our west will keep unsettled weather in the forecast
with chances for showers and a few storms continuing through much
of next week.


Spotter activation will not be needed.


Hazardous Weather Outlook
National Weather Service Riverton WY
200 AM MDT Sun May 20 2018

Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Big Horn Basin-Southwest Big Horn Basin-
Southeast Big Horn Basin-Owl Creek and Bridger Mountains-
Bighorn Mountains West-Bighorn Mountains Southeast-
Northeast Johnson County-Southeast Johnson County-
Teton and Gros Ventre Mountains-Jackson Hole-
Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
200 AM MDT Sun May 20 2018

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...Today and Tonight

Isolated afternoon and evening thunderstorms mainly over western
and southern portions.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Monday...Isolated afternoon and evening thunderstorms mainly over
northern and western portions.

Tuesday...Widespread showers and thunderstorms by late afternoon.
Locally heavy rain and gusty winds the main threat, especially
east of the Divide.

Wednesday...A chance of afternoon and evening thunderstorms.

Thursday...A chance of afternoon and evening thunderstorms over
and near the mountains. Isolated thunderstorms elsewhere.


Spotter activation will not be needed today or tonight.


Hydrologic Outlook


447 PM MDT Sun May 20 2018

...Precipitation and warm temperatures push rivers and streams
higher this week...

The weather pattern is shaping up to bring a good chance for
showers and thunderstorms this week, especially Tuesday night
through Thursday. The potential for locally heavy rainfall will
exist with any thunderstorms through the week, and Tuesday night
through Thursday could see significant widespread precipitation.
In addition to the precipitation potential, temperatures through
the week are expected to be warm. Highs in the 70s Monday through
Wednesday could reach the mid 80s for Thursday into next weekend.
These warmer temperatures are expected to accelerate snowmelt
later in the week.

With more precipitation and warmer temperatures expected, river
forecasts show rising water levels through the week. This will
keep the Musselshell River near to above flood stage upstream of
Roundup, and may push other rivers and streams near or above
bankfull by mid to late week. Those living along waterways should
pay close attention to the forecast.

Now is the time to make final preparations for runoff and move
any equipment and livestock to higher ground.

Even at levels below flood stage, bank erosion can be significant
and there is danger from undercut river banks collapsing, so stay
away from the waters edge and keep a close eye on children when
near flowing water.

If flooding is noticed please report it to local law enforcement.


Hydrologic Outlook
Hydrologic Outlook
National Weather Service Riverton WY
1000 AM MDT SUN MAY 20 2018

...River rises are expected for the  Wind River at Dubois,
Crowheart, Kinnear and Riverton through Sunday May 27th...

.Hydrologic summary:

Recent heavy rainfall of one to two inches across Fremont county,
combined with current and expected snow melt from the Wind River
mountains, is expected to cause rising river levels on the Wind
River from Dubois to Riverton through Sunday May 27th.

For the Wind River near Dubois...The latest stage is 4.1 feet on
Sunday May 20th at 10:00 AM MDT. Flood stage is 5.0 feet. The
river is forecast to rise to around flood stage...rising to a stage
of 5.1 feet by Thursday May 24rd remaining near this level through
Friday May 25th.

For the Wind River near Crowheart...The latest stage is 8.1 feet on
Sunday May 20th at 10:00 AM MDT. Flood stage is 10.0 feet. The
river is forecast to rise to 9.4 feet on Thursday May 24th remaining
below flood stage through Friday May 25th.

For the Wind River near Kinnear ...The latest stage is 6.6 feet on
Sunday May 20th at 10:00 AM MDT. Flood stage is 9.0 feet. The river
is forecast to rise to 8.2 feet on Friday May 25 th remaining below
flood stage.

For the Wind River at Riverton ...The latest stage is 6.5 feet on
Sunday May 20th at 10:00 AM MDT.  Flood stage is 9.0 feet. The river
is forecast to rise to around flood stage at 9.0 feet on Thursday
May 24th.  The river may reach as high as 9.7 feet on Friday May
25th, and remain at or near flood stage through Sunday May 27th.

If you are along the Wind River between Dubois and Riverton, and
have experienced flooding from snow melt run off combined with
runoff from heavy rainfall in the past, you should prepare this
week for possible flooding through Sunday May 27th.


RIVER/STATION            FS     TDY    F O R E C A S T
  DUBOIS WY 6NW           5.0    4.1   CREST NEAR 5.1 FT 05/24 AM
                                       2nd CREST NEAR 5.1 FT 05/29 AM
  CROWHEART WY 10SE      10.0    8.1   CREST NEAR 9.4 FT 05/24 PM
  KINNEAR WY 2SW          9.0    6.6   CREST NEAR 8.2 FT 05/25 AM
  RIVERTON WY 1SE         9.0    6.5   CREST NEAR 9.7 FT 05/25 AM

Graphical forecasts are available at:
Visit and select the rivers & lakes tab for
graphical forecasts and additional information.


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NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
Page last modified: June 2, 2009
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