Flood Potential Outlook
Issued by NWS Duluth, MN

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000
FGUS73 KDLH 202015
ESFDLH
MNC001-017-021-031-035-061-071-075-115-137-WIC003-007-013-031-
051-099-113-129-062200-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE DULUTH MN
215 PM CST THU FEB 20 2014

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 THAT 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:  2/25/2014 - 5/26/2014

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:SNAKE RIVER
PINE CITY            9.0   10.0   11.0 :  <5    7   <5   <5   <5   <5
:MISSISSIPPI RIVER
AITKIN              12.0   15.0   18.0 :  64   46   30   23   <5   <5
FORT RIPLEY         10.0   12.5   26.0 :  58   38   15   12   <5   <5
:ST. LOUIS RIVER
SCANLON             10.5   11.0   13.0 :  15   10   12    9   <5   <5

LEGEND
CS = CONDITIONAL SIMULATION (CURRENT OUTLOOK)
HS = HISTORICAL SIMULATION
FT = FEET

IN TABLE 2 BELOW...THE 95 THROUGH 5 PERCENT COLUMNS INDICATE THE
PROBABILITY OF EXCEEDING THE LISTED STAGE LEVELS (FT) FOR THE VALID
TIME PERIOD.

...TABLE 2--EXCEEDANCE PROBABILITIES...

                               CHANCE OF EXCEEDING STAGES
                                  AT SPECIFIC LOCATIONS
                          VALID PERIOD: 2/25/2014 - 5/26/2014
LOCATION              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:SNAKE RIVER
PINE CITY             6.1    6.3    6.7    7.2    7.9    8.6    9.1
:MISSISSIPPI RIVER
AITKIN                9.1    9.9   11.4   13.2   15.4   16.6   18.8
FORT RIPLEY           8.2    8.6    9.5   10.5   11.8   13.0   14.1
:ST. LOUIS RIVER
SCANLON               6.7    7.2    7.9    8.6   10.1   11.3   12.2

IN TABLE 3 BELOW...THE 95 THROUGH 5 PERCENT COLUMNS INDICATE THE
PROBABILITY OF FALLING BELOW THE LISTED STAGE LEVELS (FT) FOR THE
VALID TIME PERIOD.

...TABLE 3--NONEXCEEDANCE PROBABILITIES...

                            CHANCE OF FALLING BELOW STAGES
                                 AT SPECIFIC LOCATIONS
                          VALID PERIOD: 2/25/2014 - 5/26/2014
LOCATION              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:SNAKE RIVER
PINE CITY             2.8    2.8    2.8    2.8    2.8    2.8    2.8
:MISSISSIPPI RIVER
AITKIN                2.3    2.2    2.2    2.1    1.6    1.6    1.5
FORT RIPLEY           3.6    3.6    3.6    3.6    3.5    3.4    3.3
:ST. LOUIS RIVER
SCANLON               2.7    2.7    2.7    2.7    2.7    2.7    2.7

DISCUSSION...

...SNOW COVER.....
SNOW DEPTH AND WATER CONTENT OF THE SNOW IS A CRITICAL COMPONENT TO
SPRING SNOW MELT FLOODING.  AT THIS TIME...SNOW DEPTHS ACROSS THE
AREA RANGE FROM 24 INCHES ALONG THE RAINY RIVER...20 INCHES IN THE
MISSISSIPPI RIVER HEADWATERS OF LEECH AND CASS LAKES..24 TO 30
INCHES WITHIN THE ST. LOUIS RIVER BASIN...21 INCHES WITHIN THE SNAKE
RIVER BASIN AND 24 TO 26 INCHES IN THE UPPER ST. CROIX AND CHIPPEWA
RIVER BASINS. CURRENT WATER EQUIVALENTS EXISTING WITHIN THE SNOW
PACK RANGE FROM 3 TO 4 INCHES IN THE CHIPPEWA BASIN. THE UPPER
MISSISSIPPI HAS 2 TO 4 INCHES OF SNOW WATER EQUIVALENT (SWE) IN THE
BASINS SNOW PACK. THE ST. LOUIS RIVER HAS AROUND 4 INCHES OF SWE.
THESE VALUES ARE ABOVE NORMAL FOR LATE FEBRUARY. THE RAINY RIVER
BASIN HAS ABOVE NORMAL SWE WITH 3 TO 5 INCHES WITHIN THE BASIN. THE
LAKE SUPERIOR BASIN HAS HIGHER VALUES OF 4 TO 6 INCHES.

...SOIL CONDITIONS AND FROST DEPTHS...
CURRENT SOIL CONDITIONS ARE MOIST WITH A NORMAL TO SHALLOWER THAN
NORMAL FROST LEVEL.  PRECIPITATION WAS 6 TO 8 INCHES BELOW NORMAL
BETWEEN JULY THROUGH AUGUST...THEN OCTOBER SAW GOOD RECOVERY PRIOR
TO FREEZE UP. THE SNOW ACCUMULATION PERIOD STARTED LATE NOVEMBER AND
AREAS OF HEAVY SNOW SINCE THEN HAVE INSULATED THE SOIL. A DEEP FROST
OF 5 TO 7 FEET CAN BE FOUND UNDER PAVEMENT. HOWEVER...UNDER SNOW AND
IN THE FOREST FROST DEPTHS ARE 12 TO 24 INCHES.

...DROUGHT CONDITIONS...
DROUGHT CONDITIONS EASED THROUGH MUCH OF THE SUMMER AFTER A VERY WET
SPRING 2013. THEN A VERY DRY SUMMER RESULTED IN ABNORMALLY DRY
CONDITIONS ACROSS THE REGION UNTIL LATE FALL WHEN HEAVY RAINS
ALLEVIATED ANY DROUGHT CONDITIONS IN OUR REGION.

...RIVER CONDITIONS...
ALL RIVERS IN THE DULUTH HYDROLOGIC SERVICE AREA REMAIN ICE
COVERED.  ACCORDING TO THE USGS AND MN DNR...THE MISSISSIPPI RIVER
HEADWATER BASINS ARE NEAR NORMAL WHILE WESTERN LAKE SUPERIOR IS
BELOW NORMAL AND THE RAINY LAKE BASIN IS WELL BELOW NORMAL.  IN
WISCONSIN THE CHIPPEWA RIVER BASIN HEADWATER FLOWS ARE BELOW NORMAL.


...WEATHER OUTLOOKS...
SHORT RANGE WEATHER FORECASTS SHOW A POTENT WINTER STORM CURRENTLY
MOVING THROUGH THE REGION. AN ADDITIONAL .50 INCHES TO 1.5 INCHES OF
LIQUID WATER EQUIVALENT IS EXPECTED THROUGH MARCH 1ST. THE CLIMATE
PREDICTION CENTER PROVIDES LONGER RANGE OUTLOOKS AND IS INDICATING
BELOW NORMAL PRECIPITATION FOR THE FIRST WEEK IN MARCH WITH BELOW
NORMAL TEMPERATURES. LOOKING AHEAD TO THE MARCH...APRIL...MAY PERIOD
THE CLIMATE PREDICTION CENTER SUGGESTS...BELOW NORMAL TEMPERATURES
AND EQUAL CHANCES OF ABOVE...NEAR AND BELOW NORMAL PRECIPITATION.

THESE LONG-RANGE PROBABILISTIC OUTLOOKS CONTAIN FORECAST VALUES THAT
ARE CALCULATED USING MULTIPLE SEASON SCENARIOS FROM 30 OR MORE YEARS
OF CLIMATOLOGICAL DATA...INCLUDING CURRENT CONDITIONS OF THE
RIVER...SOIL MOISTURE...SNOW COVER...AND 30 TO 90 DAY LONG-RANGE
OUTLOOKS OF TEMPERATURE AND PRECIPITATION. BY PROVIDING A RANGE OF
PROBABILITIES...THE LEVEL OF RISK ASSOCIATED WITH LONG-RANGE PLANNING
DECISIONS CAN BE DETERMINED. THESE PROBABILISTIC FORECASTS ARE PART
OF THE NATIONAL WEATHER SERVICE`S ADVANCED HYDROLOGIC PREDICTION
SERVICE.

VISIT OUR WEB SITE WEATHER.GOV/DLH FOR MORE WEATHER AND WATER
INFORMATION.

FOR ADDITIONAL INFORMATION ON STREAM FLOW CONDITIONS FOR USGS
LOCATIONS PLEASE REFERENCE
FOR MINNESOTA   WWW.WATERDATA.USGS.GOV/MN/NWIS/RT
FOR WISCONSIN   WWW.WATERDATA.USGS.GOV/WI/NWIS/RT

FOR ADDITIONAL INFORMATION ON STREAM FLOW CONDITIONS AT
MN DNR LOCATIONS...REFERENCE
WWW.DNR.STATE.MN.US/WATERS/CSG/INDEX.HTML
OR
CLIMATE.UMN.EDU/DOW/WEEKLY_STREAM_FLOW/STREAM_FLOW_WEEKLY.ASP

FOR MORE INFORMATION ON CLIMATE OUTLOOKS REFERENCE
WWW.CPC.NCEP.NOAA.GOV

THE NEXT OUTLOOK WILL BE ISSUED THURSDAY...MARCH 6.

$$






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