Flood Potential Outlook
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
000
FGUS73 KBIS 231818
ESFBIS
NDC009-013-023-049-061-069-075-079-101-301800-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE BISMARCK ND
1216 PM CST FRI JAN 23 2015


...FLOOD AND WATER RESOURCES OUTLOOK...

THIS PROBABILISTIC FLOOD OUTLOOK IS FOR THE SOURIS (MOUSE) RIVER
BASIN OF WESTERN AND CENTRAL NORTH DAKOTA...COVERING THE TIME PERIOD
OF LATE JANUARY THROUGH LATE APRIL.

THE FOLLOWING MESSAGE HAS FOUR SECTIONS...THE FIRST PROVIDES SOME
TEXT ON HIGHLIGHTS OF THIS PRODUCT AND CONDITIONS AFFECTING LOCAL
HYDROLOGY. THE SECOND GIVES THE CURRENT AND NORMAL/HISTORICAL
CHANCES OF RIVER LOCATIONS REACHING THEIR MINOR...MODERATE AND
MAJOR FLOOD CATEGORY...THE THIRD GIVES THE CURRENT CHANCES OF
RIVER LOCATIONS RISING ABOVE RIVER STAGES LISTED...AND THE FINAL
SECTION COVERS THE RISK OF RIVERS FALLING BELOW LISTED STAGES.

...FLOOD OUTLOOK OVERVIEW HIGHLIGHTS...
IN GENERAL...WELL BELOW NORMAL TO NEAR NORMAL FLOOD RISK IS
REPRESENTED IN THE FOLLOWING TABLES. THOSE SITES WITH THE HIGHER
RISK TEND TO BE THOSE WHICH ARE MORE SUSCEPTIBLE TO HEAVY SPRING
RAINS.


...CURRENT CONDITIONS...
FROST DEPTH ACROSS THE REGION IS NOT NEARLY AS DEEP AS IT WAS LAST
YEAR AT THIS TIME. FROST DEPTHS OF A LITTLE OVER 30 INCHES ARE COMMON
AND THIS POSES NO UNUSUAL RISK. SNOWPACK AND ITS WATER EQUIVALENT
RANGES FROM A TRACE OF WATER IN AREAS NEAR THE LITTLE MISSOURI RIVER
TO NEARLY AN INCH OF WATER IN PLACES ALONG THE UPPER JAMES RIVER
BASIN. A FEW SMALL AREAS WITH NEARLY 2 INCHES OF WATER EQUIVALENT
MAY BE PRESENT...BUT ARE NOT WIDESPREAD ENOUGH TO CREATE AN ENHANCED
RISK OF FLOODING. SOIL MOISTURE LEVELS...WHICH WERE HIGH FOR MOST OF
THE SUMMER...WERE BROUGHT BACK DOWN TO A MORE NORMAL RANGE DUE TO
THE WARM AND DRY SEPTEMBER AND OCTOBER. ICE THICKNESS IS NEAR NORMAL
TO SOMEWHAT BELOW NORMAL ON LOCAL RIVERS AND STREAMS. THIS WOULD
SUGGEST THAT PROBLEMS ASSOCIATED WITH EXCESSIVE ICE ARE ALSO NOT AT
LEVELS SEEN THE PAST FEW YEARS. ABOUT THE ONLY HISTORICALLY UNUSUAL
CONDITION THAT IS STILL PRESENT ACROSS THE BASIN ARE THE FULL TO
OVER FULL PONDS...WETLANDS...AND OTHER SMALL SURFACE WATERS.


...WEATHER OUTLOOK...
THE 6 TO 10 AND 8 TO 14 DAY WEATHER OUTLOOKS STILL REFLECT WARMER
THAN NORMAL TEMPERATURES IN THE NEAR TERM WITH A SHIFT TOWARDS MORE
NORMAL TEMPERATURE RANGES IN EARLY FEBRUARY. PROBABILITY OF
PRECIPITATION DURING THE SAME PERIOD IS SLIGHTLY ELEVATED...BUT
NOTHING SUGGESTS ANY SIGNIFICANT AMOUNTS ARE EXPECTED. LOOKING AHEAD
TO THE ONE MONTH AND THREE MONTH OUTLOOKS...THERE IS GENERALLY AN
EQUAL CHANCE OF ABOVE NORMAL...NEAR NORMAL...AND BELOW NORMAL
TEMPERATURES AND PRECIPITATION.


...SUMMARY OF HYDROLOGIC CONDITIONS...
ALL RIVERS AND STREAMS ARE NEAR NORMAL TO SLIGHTLY ELEVATED FOR THIS
TIME OF YEAR. RESERVOIRS WITH FLOOD CONTROL STORAGE ARE EITHER
ALREADY AT THEIR DESIGNATED DRAWDOWN LEVELS...OR ON TRACK TO MEET
THEIR FEBRUARY TARGETS.



...LONG-RANGE PROBABILISTIC RIVER OUTLOOK BY FLOOD CATEGORY...


                           SOURIS RIVER BASIN
                    LONG-RANGE PROBABILISTIC OUTLOOK

THE TABLE BELOW GIVES BOTH THE CURRENT CHANCES (CS) AND THE
NORMAL/HISTORICAL CHANCES (HS) FOR EXCEEDING THE MINOR...MODERATE
AND MAJOR FLOOD STAGES AT THE RIVER FORECAST POINT LOCATIONS DURING
THE VALID PERIOD OF THIS OUTLOOK.

        PROBABILITIES FOR MINOR...MODERATE AND MAJOR FLOODING
                     FROM  1/26/2015 TO 4/26/2015

TABLE 1                                  : CURRENT AND HISTORICAL
                                         : CHANCES OF EXCEEDING FLOOD
                                         : CATEGORY IN PERCENT (%)
                         CATEGORICAL     :
                      FLOOD STAGES (FT)  :  MINOR   MODERATE  MAJOR
LOCATION            MINOR    MOD   MAJOR :  CS HS    CS HS    CS HS
--------            ------ ------ ------ : --- ---  --- ---  --- ---
DES LACS RIVER.....
  FOXHOLM             16.0   18.0   19.0 :  <5  <5   <5  <5   <5  <5
SOURIS RIVER.....
  SHERWOOD            18.0   20.0   25.0 :  <5   6   <5  <5   <5  <5
  SOURIS NR FOXHOLM   10.0   13.0   15.0 :  38  87   29  70   <5  <5
  MINOT 4NW           14.0   17.0   22.0 :  <5  13   <5  <5   <5  <5
  MINOT             1549.0 1551.0 1555.0 :  <5  <5   <5  <5   <5  <5
  LOGAN               34.0   36.0   38.0 :   7  18   <5   6   <5  <5
  SAWYER              22.0   24.0   26.0 :  <5   6   <5  <5   <5  <5
  VELVA             1505.0 1510.0 1515.0 :  <5  16   <5  <5   <5  <5
WINTERING RIVER.....
  KARLSRUHE            7.0    9.0   10.0 :  <5  12   <5  <5   <5  <5
SOURIS RIVER.....
  TOWNER              52.0   54.0   56.0 :  43  87   23  36   <5   6
  BANTRY              11.0   12.0   14.0 :  40  86   21  38   <5   6
WILLOW CREEK.....
  WILLOW CITY         10.0   14.0   16.0 :  30  33    6  13   <5  <5
SOURIS RIVER.....
  WESTHOPE            10.0   14.0   16.0 :  24  40   <5  20   <5  12

LEGEND:
    CS  =  CONDITIONAL SIMULATION (OUTLOOK FOR CURRENT CONDITIONS)
    HS  =  HISTORICAL SIMULATION  (HISTORICAL RISK FOR THIS SEASON)
    FT  =  FEET ABOVE GAGE ZERO DATUM


...LONG-RANGE PROBABILISTIC OUTLOOK BY RIVER STAGE...


                          SOURIS RIVER BASIN
                    LONG-RANGE PROBABILISTIC OUTLOOK

THE TABLE BELOW GIVES THE CURRENT 95 THROUGH 5 PERCENT CHANCES FOR
EXCEEDING RIVER STAGES AT THE RIVER FORECAST POINT LOCATIONS DURING
THE VALID PERIOD OF THIS OUTLOOK.

EXAMPLE: DURING THE VALID TIME OF THIS OUTLOOK...THERE IS A
         95 PERCENT CHANCE FOR THE SOURIS RIVER AT SHERWOOD TO
         RISE ABOVE 5.5 FEET AND ONLY A 5 PERCENT CHANCE THAT
         IT WILL RISE ABOVE 16.8 FEET.

           PROBABILITIES FOR EXCEEDING LISTED RIVER STAGES
                     FROM  1/26/2015 TO 4/26/2015
TABLE 2

LOCATION              95%    90%    75%    50%    25%    10%    05%
--------             -----  -----  -----  -----  -----  -----  -----
DES LACS RIVER.....
  FOXHOLM              5.3    6.0    6.4    6.9    7.5    8.7   12.6
SOURIS RIVER.....
  SHERWOOD             5.5    6.1    7.5    9.5   14.1   16.3   16.8
  SOURIS NR FOXHOLM    7.0    7.1    7.8    9.2   13.5   14.0   14.2
  MINOT 4NW            5.1    5.3    6.0    7.2   11.5   12.6   13.9
  MINOT             1540.9 1541.0 1541.5 1541.9 1544.0 1544.9 1547.5
  LOGAN               22.2   22.4   24.2   25.5   30.9   33.7   35.6
  SAWYER               8.3    8.5    9.7   11.1   16.8   19.3   21.2
  VELVA             1491.6 1491.7 1493.4 1495.1 1502.4 1504.4 1505.4
WINTERING RIVER.....
  KARLSRUHE            2.3    2.4    2.7    3.0    3.2    3.9    5.4
SOURIS RIVER.....
  TOWNER              47.1   47.4   48.9   51.0   53.8   54.5   55.4
  BANTRY               4.8    5.1    6.9    8.7   11.8   12.5   13.2
WILLOW CREEK.....
  WILLOW CITY          5.1    5.2    5.6    6.4   11.4   13.4   14.5
SOURIS RIVER.....
  WESTHOPE             7.5    7.7    8.0    8.9   10.0   11.0   12.3



...LONG-RANGE PROBABILISTIC OUTLOOK BY RIVER STAGE...


                          SOURIS RIVER BASIN
                    LONG-RANGE PROBABILISTIC OUTLOOK

THE TABLE BELOW GIVES THE CURRENT 95 THROUGH 5 PERCENT CHANCES FOR
THE RIVERS TO FALL BELOW THE LISTED RIVER STAGES AT THE RIVER
FORECAST
POINT LOCATIONS DURING THE VALID PERIOD OF THIS OUTLOOK.

EXAMPLE: DURING THE VALID TIME OF THIS OUTLOOK...THERE IS A
         95 PERCENT CHANCE FOR THE SOURIS RIVER AT SHERWOOD TO
         REMAIN ABOVE 0.6 FEET AND ONLY A 5 PERCENT CHANCE THAT
         IT WILL FALL BELOW 0.6 FEET.

         PROBABILITIES FOR FALLING BELOW LISTED RIVER STAGES
                        1/26/2015 - 4/26/2015

TABLE 3

LOCATION              95%    90%    75%    50%    25%    10%    05%
--------             -----  -----  -----  -----  -----  -----  -----
DES LACS RIVER.....
  FOXHOLM              4.6    4.6    4.6    4.5    4.5    4.5    4.5
SOURIS RIVER.....
  SHERWOOD             0.6    0.6    0.6    0.6    0.6    0.6    0.6
  SOURIS NR FOXHOLM    4.5    4.5    4.5    4.5    4.5    4.5    4.5
  MINOT 4NW            3.9    3.9    3.9    3.9    3.9    3.9    3.9
  MINOT             1536.1 1536.1 1536.1 1536.1 1536.1 1536.1 1536.1
  LOGAN               18.7   18.7   18.7   18.7   18.7   18.7   18.7
  SAWYER               5.4    5.4    5.4    5.4    5.4    5.4    5.4
  VELVA             1489.0 1489.0 1489.0 1489.0 1489.0 1489.0 1489.0
WINTERING RIVER.....
  KARLSRUHE            1.6    1.6    1.6    1.6    1.6    1.6    1.6
SOURIS RIVER.....
  TOWNER              43.8   43.8   43.8   43.8   43.8   43.6   43.6
  BANTRY               2.0    2.0    2.0    2.0    1.9    1.8    1.8
WILLOW CREEK.....
  WILLOW CITY          4.6    4.6    4.6    4.6    4.6    4.6    4.6
SOURIS RIVER.....
  WESTHOPE             6.1    6.0    6.0    6.0    6.0    6.0    5.9


...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 ENSEMBLE STREAMFLOW PREDICTION MODEL (ESP). THE MODEL
IS RUN FOR MULTIPLE SCENARIOS STARTING AT CURRENT RIVER...SNOW AND
SOIL CONDITIONS AND USING NEARLY 50 YEARS OF PAST PRECIPITATION AND
TEMPERATURE CONDITIONS IN THE HISTORICAL RECORD. 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).

THE PROBABILITIES CAN BE USED FOR RISK MANAGEMENT BY COMPARING THIS
YEARS CURRENT TEMPERATURE AND PRECIPITATION OUTLOOKS WITH
THOSE OF PAST YEARS USED IN THE HYDRO OUTLOOK. THEY CAN ALSO BE
USED 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
IS CONTRIBUTING TO THE AREAS 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 1948 THROUGH 2011.

...ADDITIONAL INFORMATION SOURCES...

THE AHPS LONG RANGE PROBABILISTIC HYDROLOGIC OUTLOOKS ARE ISSUED
NEAR THE END OF EACH 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 BISMARCK AHPS WEB
PAGE ON THE INTERNET AT:

        WWW.WEATHER.GOV/BISMARCK OR WEATHER.GOV/BIS

 THEN CLICK ON THE "RIVERS AND LAKES AHPS" ON THE TAB ABOVE THE
MAP...OR ON THE LINK IN THE BLUE-LEFT-HAND BANNER.

CURRENT RIVER CONDITIONS FOR ALL FORECAST POINTS WITHIN THE SOURIS
RIVER BASIN ARE AVAILABLE ON OUR WEB SITE...AS WELL AS THE FORECASTS
WHEN THE RIVER AT THE FORECAST POINT IS IN OR NEAR FLOOD.

IF YOU HAVE ANY QUESTIONS...CONTACT THE NWS AT 701-250-4495.

PROBABILISTIC HYDROLOGIC OUTLOOKS WILL BE ISSUED MONTHLY THROUGHOUT
THE REST OF THE YEAR DURING THE LATER PART OF THE MONTH OR AS
CONDITIONS WARRANT.


$$
AJS









USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.