Flood Potential Outlook
Issued by NWS Grand Forks, ND

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MNC005-007-027-029-051-057-069-077-087-089-107-111-113-119-125-
135-159-167-NDC003-005-017-019-027-035-039-063-067-071-073-077-
081-091-095-097-099-301200-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE EASTERN NORTH DAKOTA/GRAND FORKS ND
950 AM CST THU MAR 05 2015

...SPRING FLOOD AND WATER RESOURCES OUTLOOK...

...RED RIVER BASIN OUTLOOK FOR RIVER FLOOD POTENTIAL...

         This Outlook covers the Red River of the North
         and its Minnesota and North Dakota tributaries.

...LOW RISK OF MINOR FLOODING FOR MOST OF THE RED RIVER BASIN...

. OUTLOOK SUMMARY...

 * Except for Fargo/Moorhead...there is a low risk (between 33% and
   5%) for minor flooding at Wahpeton/Breckenridge...Halstad...Grand
   Forks...Oslo and Pembina on the Mainstem Red; on the Minnesota
   tributaries...Sabin and Dilworth on the Buffalo...Hendrum on the
   Wild Rice and Hallock on the Two Rivers River; and on the North
   Dakota tributaries...Abercrombie on the Wild Rice...Kindred and
   Harwood on the Sheyenne...West Fargo on the diversion...Mapleton
   south of I-94 on the Maple River and Minto on the Park River.

 * There is a medium risk (41%) of minor flooding above 18 feet at
   Fargo/Moorhead on the Red with low risks (9%) of moderate and
   (6%) major flooding there.

 * Also...there is a low risk of moderate flooding at Oslo...as
   well as Abercrombie and Harwood on the North Dakota tributaries.

. VALID PERIOD OF OUTLOOK...

 * This 90-day Outlook covers the period from March 9th, 2015 to
    June 7th, 2015...a bit further out than the previous outlook
     which went out to May 24th.

. OUTLOOK DISCUSSION...

  Hydrologic and Climate conditions which affect each of the several
   factors that significantly determine the timing and magnitude of
    spring snowmelt flooding within the Red River of the North are
     discussed below:

 * SNOWPACK CONDITIONS...
   Snowpack conditions have not changed significantly since the last
    outlook. Snow depths range from 2 to 15 inches across the
     region with lesser amounts in the southern Red river basin as
      well as the Sheyenne River basin. Highest amounts appear in
       the northern tier of counties along the US-Canadian border
        which include parts of the Pembina...Two Rivers...Tamarac
         and Roseau River basins.

    Overall...snowpack moisture is less than an inch across the
     southern two thirds of the Red River basin and from one to
      two inches across the northern third.

 * SOIL MOISTURE AND FROST DEPTHS...
   The U.S. Drought Monitor shows the Red River and Devils Lake
    Basins as abnormally dry for the most part with short-term
     moderate drought for the valley proper and a bit west from its
      headwaters near Lake Traverse northward to around Grand Forks.

   NWS Climate Prediction Center`s Soil moisture analysis indicate
    that most of the Red River and Devils Lake Basins are in a 2 to
     3 inch moisture deficit for this water year...with the driest
      parts within the central Red Basin and extending eastward into
       Minnesota up to the Lake of the Woods/Northwest Angle region.

   With the continuing sub-freezing temperatures and lack of a deep
    insulating snowpack...frost depths have increased to three to
     four feet across the basin.

 * RIVER FLOWS...
   Most rivers are ice covered and smaller streams are frozen solid
with
    base flows mainly within the long-term normals...ranging between
the
     25th and 75th percentiles for winter flows.

 * RIVER ICE...
   River ice has grown a bit with the cold weather with reports of
    up to two and a half feet on some of the quieter parts of the
     larger rivers and streams in the basin and up to 3 feet on
      lakes and ponds.

 * FACTORS YET TO BE DETERMINED...
    - Further snowpack growth,
    - Rate of snowmelt/thaw,
    - Heavy rain on snow or frozen ground during thaw or peak flood,
    - Heavy rain on ice-covered rivers causing short-term ice jams.

* SHORT TERM WEATHER FORECAST...
  Expect a warming trend from this week into next, with brief periods
   of very light snow possible.

* SPRING FLOOD SEASON CLIMATE OUTLOOK...
  Expect temperatures to trend above normal through mid-March and
   near normal from late March into April, with below normal precip
    into mid-March and near normal precip from late March into April.

. NEXT FLOOD OUTLOOK...Unless conditions warrant...the next
   numerical flood outlook will not be issued until after the spring
    snowmelt flooding recedes. However...periodic Spring Thaw
     Progress Outlooks will be issued. The next numerical outlook
      That will be the regularly scheduled monthly release...toward
       the end of April, 2015.

. FLOOD OUTLOOK PROBABILITIES TABLES...

The following message has two sections...the first gives the
 current and normal/historical chances of river locations reaching
  their Minor...Moderate...and Major Flood Category...the second
   gives the current chances of river locations rising above river
    stages listed.


...Red River Long-Range Probabilistic Outlook by Flood Category...

              Valid from March 9, 2015  to June 7, 2015

In Table 1 below...the current (CS) and historical (HS) or normal
 probabilities of exceeding minor...moderate...and major flood stages
 are listed for the valid time period.

CS values indicate the probability of reaching a flood category
 based on current conditions.

HS values indicate the probability of reaching a flood category
 based on historical or normal conditions.

When the value of CS is more than HS...the probability of
 exceeding tat level is higher than normal. When the value of CS is
 less than HS...the probability of exceeding that level is lower
 than normal


...Table 1--Probabilities for minor...moderate and major flooding
                 Valid Period:   3/9/2015 - 6/7/2015

                                         : Current and Historical
                                         :  Chances of Exceeding
                                         :    Flood Categories
                                         :   as a Percentage (%)
                         Categorical     :
                      Flood Stages (FT)  :  Minor   Moderate  Major
Location            Minor    Mod   Major :  CS HS    CS HS    CS HS
--------            ------ ------ ------ : --- ---  --- ---  --- ---
RED RIVER OF THE NORTH.....
  WAHPETON            11.0   13.0   15.0 :  20  53   <5  24   <5  12
  HICKSON             30.0   34.0   38.0 :  <5  20   <5  12   <5  <5
  FARGO               18.0   25.0   30.0 :  41  76    9  36    6  23
  HALSTAD             26.0   32.0   37.5 :   6  33   <5  18   <5   7
  GRAND FORKS         28.0   40.0   46.0 :  10  58   <5  32   <5   9
  OSLO                26.0   30.0   36.0 :  15  61   10  55   <5  18
  DRAYTON             32.0   38.0   42.0 :  <5  41   <5  32   <5   9
  PEMBINA             39.0   44.0   49.0 :   6  55   <5  41   <5  21
MINNESOTA TRIBUTARIES.....
  SABIN*              13.0   15.0   19.0 :  23  49   <5  13   <5  <5
  HAWLEY*              8.0    9.0   11.0 :  <5  36   <5  23   <5  <5
  DILWORTH*           13.0   20.0   26.0 :  27  66   <5  20   <5  <5
  TWIN VALLEY         10.0   12.0   14.0 :  <5  16   <5  <5   <5  <5
  HENDRUM             20.0   28.0   32.0 :  10  52   <5  21   <5  <5
  SHELLY              14.0   20.0   23.0 :  <5  30   <5  10   <5   6
  CLIMAX              20.0   25.0   30.0 :  <5  23   <5   9   <5   6
  HIGH LANDING        12.0   12.5   13.0 :  <5  30   <5  26   <5  24
  CROOKSTON           15.0   23.0   25.0 :  <5  52   <5  12   <5   7
  ABOVE WARREN        67.0   71.0   75.0 :  <5  12   <5  <5   <5  <5
  ALVARADO           106.0  108.0  110.0 :  <5  20   <5  13   <5  <5
  HALLOCK            802.0  806.0  810.0 :  18  58   <5  41   <5   9
  ROSEAU              16.0   18.0   19.0 :  <5  21   <5  12   <5   9
NORTH DAKOTA TRIBUTARIES.....
  ABERCROMBIE         10.0   12.0   18.0 :   9  36    6  33   <5  18
  VALLEY CITY         15.0   16.0   17.0 :  <5  10   <5   9   <5   6
  LISBON              15.0   17.0   19.0 :  <5  10   <5   7   <5  <5
  KINDRED             16.0   19.0   20.5 :   6  21   <5  12   <5   9
  WEST FARGO DVRSN    18.0   20.0   21.0 :   7  23   <5  18   <5  12
  HARWOOD            884.0  886.0  891.0 :   7  23    6  20   <5  10
  ENDERLIN             9.5   12.0   14.0 :  <5  20   <5   9   <5  <5
  MAPLETON           905.0  908.0  910.0 :  10  32   <5  13   <5  <5
  HILLSBORO           10.0   13.0   16.0 :  <5  15   <5   9   <5  <5
  MINTO                6.0    8.0   11.0 :   6  24   <5   6   <5  <5
  GRAFTON             12.0   13.5   14.5 :  <5  16   <5  <5   <5  <5
  WALHALLA            11.0   16.0   18.0 :  <5  18   <5  <5   <5  <5
  NECHE               18.0   19.0   20.5 :  <5  27   <5  24   <5  16

LEGEND:
    CS  =  Conditional Simulation (Outlook for current conditions)
    HS  =  Historical  Simulation ( "       "  normal  conditions)
    FT  =  Feet                   (above gage zero datum)
 * These are new flood stages...one foot above the previous values.


...Red River Long-Range Probabilistic Outlook by River Stage...

              Valid from March 9, 2015  to June 7, 2015



LOCATION              95%    90%    75%    50%    25%    10%    05%
--------            ------ ------ ------ ------ ------ ------ ------
Red River of the North.....
  WAHPETON             6.1    6.6    7.9    8.8   10.7   12.0   13.2
  HICKSON             12.1   12.5   14.4   16.9   22.1   25.7   28.9
  FARGO               15.4   15.6   16.3   17.3   20.4   24.9   30.4
  HALSTAD              6.2    7.2    9.2   12.4   17.0   22.1   26.1
  GRAND FORKS         17.2   17.5   18.1   19.7   22.6   30.8   35.0
  OSLO                 9.8   10.7   12.1   16.4   21.9   31.1   33.5
  DRAYTON             12.8   13.3   14.3   17.1   21.6   28.2   32.2
  PEMBINA             15.3   16.1   18.5   23.1   29.3   37.3   41.4


MINNESOTA TRIBS:      95%    90%    75%    50%    25%    10%    05%
--------            ------ ------ ------ ------ ------ ------ ------
South Fork Buffalo River.....
  SABIN                8.5    8.7   10.1   11.7   12.8   14.2   14.5
Buffalo River.....
  HAWLEY               3.9    4.1    4.2    4.6    5.2    5.9    6.5
  DILWORTH             6.1    6.5    8.1   10.8   13.9   16.8   17.9
Wild Rice River.....
  TWIN VALLEY          2.9    3.0    3.3    3.9    4.9    6.3    6.7
  HENDRUM              3.6    4.3    5.5    9.8   14.8   20.5   21.9
Marsh River.....
  SHELLY               3.9    4.0    4.3    5.4    7.0    9.1   11.0
Sand Hill River.....
  CLIMAX               5.0    5.0    5.7    6.5    8.0   11.7   13.3
Red Lake river.....
  HIGH LANDING         9.1    9.2    9.4    9.6    9.9   10.5   10.6
  CROOKSTON            7.8    8.0    8.5    9.7   11.3   13.5   15.1
Snake River.....
  ABOVE WARREN        61.2   61.4   61.7   62.1   62.7   64.3   65.3
  ALVARADO            96.8   97.0   97.5   98.3  100.1  102.3  104.2
Two Rivers River.....
  HALLOCK            796.3  796.6  796.9  797.7  799.9  803.6  806.1
Roseau River.....
  ROSEAU               6.6    6.8    7.0    7.9    9.7   11.0   14.6


NORTH DAKOTA TRIBS:   95%    90%    75%    50%    25%    10%    05%
--------            ------ ------ ------ ------ ------ ------ ------
Wild Rice River.....
  ABERCROMBIE          1.5    1.8    2.6    3.7    5.5    9.9   14.1
Sheyenne River.....
  VALLEY CITY          4.0    4.0    4.2    5.0    6.4    8.9   10.2
  LISBON               2.7    2.8    3.1    4.0    5.7   10.2   12.9
  KINDRED              2.7    2.8    3.3    5.4    7.6   13.6   17.0
  WEST FARGO DVRSN     9.7    9.9   10.1   11.8   12.8   16.3   20.4
  HARWOOD            867.7  868.5  869.8  873.9  876.9  880.4  889.0
Maple River.....
  ENDERLIN             1.9    2.2    3.7    5.2    6.8    8.5    9.8
  MAPLETON           894.5  895.3  896.1  899.0  901.5  905.5  907.5
Goose River.....
  HILLSBORO            1.7    1.7    1.9    2.6    3.5    4.8    5.8
Forest River.....
  MINTO                1.5    1.5    1.6    2.1    3.7    5.4    7.0
Park River.....
  GRAFTON              7.4    7.5    7.6    8.0    8.8    9.3   11.0
Pembina River.....
  WALHALLA             2.6    2.7    2.9    3.9    5.1    7.8    8.7
  NECHE                3.9    4.2    4.8    6.5    8.7   15.2   15.4


.THE OUTLOOK PRODUCTION PROCESS...

This long range probabilistic outlook is based on a series of peak
 river levels or crests taken from the forecast hydrograph results
 of the NWS Community Hydrologic Prediction System (CHPS). The model
 is run for multiple scenarios starting at current river, low and
 soil conditions and using over 60 years of past precipitation and
 temperature conditions that were experienced for those past years
 during the time-frame of the outlook period. These crests can then
 be ranked from lowest to highest, and then be assigned an
 exceedance probability. For example, For a series of 50 years, the
 lowest ranked crest has 49 crests above it and since 95 percent
 of the crests are above it, it is assigned a 95 percent probability
 of exceedance (POE).

A YouTbe video on "How to Interpret River Outlook Products" is at:

             www.youube.com/watch?v=pSoEgvsnpv4

The probabilities can be used for risk management by using them as
 an indication of the range of crests that may be expected during
 the valid period of the outlook.

By providing a range of peak river level probabilities, the NWS is
 contributing to the area`s Decision Support Services that help
 with long-range flood planning and response readiness. This outlook
 is a part of NOAA/S National Weather Service`s AHPS (Advanced
 Hydrologic Prediction Services).

This outlook was produced using precipitation and temperatures
 for the years 1949 through 2012.

. ADDITIONAL INFORMATION SOURCES...

The AHPS Long-Range Probabilistic Hydrologic Outlooks are issued
 each month typically between the first and second Friday after
 mid-month. However...Spring Flood and Water Resources Outlooks are
 issued several times during the critical spring melt period...
 usually on Thursdays beginning in late February or early March and
 ending in early April...depending on the spring flooding conditions.

This outlook is also presented as graphs of the probability of stage
 exceedance for the full period and for weekly intervals during the
 period. These graphs...together with explanations that help in
 interpreting them are available from the NWS Grand Forks AHPS web
 page on the Internet at:

        www.weather.gov/grandforks OR weather.gov/fgf

  Then click on the "Rivers and Lakes AHPS" on the tab above the map
  ...or on the same link in the blue, left-hand banner.

Current river conditions for all river forecast points in the Red
 River of the North and Devils/Stump Lake conditions are also
  available on our web site...as well as the 7-day forecasts when
   the river at the forecast point is in or near flood.

If you have any questions...contact the NWS at 701-772-0720.

A new...point specific flood briefing page is available at:

   www.crh.noaa.gov/fgf/briefing/floodbriefing.php

Also...7-day deterministic forecasts will be issued at least once a
 day when the river forecast locations will be in flood during that
  period.

Probabilistic Hydrologic Outlooks will be issued monthly throughout
 the rest of the year during the later part of the month or as
  conditions warrant.

Refer to the separate Devils Lake Probabilistic Hydrologic Outlook
 for Devils and Stump Lakes Probability of Exceedance levels and
  low-water non-exceedance levels.

You can follow us on Facebook at: www.facebook.com/NWSGrandForks
 and on Twitter at: @NWSGrandForks

$$

www.weather.gov/fgf








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