Probabilistic Hydrologic Outlook
National Weather Service Gaylord MI
1029 AM EDT Thu Mar 14 2024

...SPRING FLOOD OUTLOOK FOR NORTHERN MICHIGAN...
 
THE SPRING 2024 FLOOD OUTLOOK FOR NORTHERN MICHIGAN INDICATES A
BELOW AVERAGE PROBABILITY OF FLOODING DUE TO SNOW MELT WITHIN
MAJOR EASTERN UPPER AND NORTHERN LOWER MICHIGAN RIVER BASINS.
 
THIS OUTLOOK COVERS CHIPPEWA AND MACKINAC COUNTIES IN EASTERN
UPPER MICHIGAN WHICH INCLUDES THE PINE RIVER BASIN...AND THE
NORTHERN HALF OF LOWER MICHIGAN ENCOMPASSING THE AU SABLE...
BOARDMAN...MANISTEE...RIFLE...AND TOBACCO RIVER BASINS.
 
THE FIRST TABLE BELOW LISTS THE PROBABILITIES OF REACHING
FLOOD STAGE (MINOR FLOODING)...AS WELL AS MODERATE AND MAJOR
FLOOD LEVELS FOR THE SIX FORECAST POINTS WITHIN THE GAYLORD
NATIONAL WEATHER SERVICE OFFICE HYDROLOGIC SERVICE AREA.  THE
CURRENT (CS) AND HISTORICAL 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/MAJOR FLOODING
               Valid Period:  03/18/2024 - 06/16/2024

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Manistee River
Sherman             15.0   16.0   17.0 :   7   12   <5   <5   <5   <5
:Boardman River
Mayfield--Brown B    7.0    8.0    9.0 :  <5   <5   <5   <5   <5   <5
:Au Sable River
Red Oak              7.0    8.0    9.0 :  <5   12   <5   <5   <5   <5
:Rifle River
Sterling             6.0   11.0   13.0 :  30   62   <5   <5   <5   <5
:Pine River
Rudyard             17.0   19.0   20.0 :  <5   <5   <5   <5   <5   <5
:Tobacco River
Beaverton           12.0   14.0   17.0 :  <5   <5   <5   <5   <5   <5

Legend
CS = Conditional Simulation (Current Outlook)
HS = Historical Simulation
FT = Feet
 
DEPARTURE FROM NORMAL OF REACHING FLOOD STAGE IS THE DIFFERENCE
BETWEEN THE CURRENT PROJECTED CHANCE FOR REACHING FLOOD STAGE (CS)
AND THE CLIMATIC NORMAL (HS).  FOR EXAMPLE...THE RIFLE RIVER NEAR
STERLING...WITH A FLOOD STAGE OF 6 FEET...HAS A 30 PERCENT CHANCE OF
REACHING OR EXCEEDING FLOOD STAGE...WHICH IS 32 PERCENTAGE POINTS
BELOW NORMAL.  DURING THE 90 DAY PERIOD LISTED...THE TYPICAL
PROBABILITY OF THE RIFLE RIVER NEAR STERLING REACHING FLOOD STAGE IS
62 PERCENT.
 
THE NEXT TABLE SHOWS THE CHANCE THAT A PARTICULAR RIVER LOCATION
COULD RISE ABOVE THE LISTED STAGES IN THE SPECIFIED 90 DAY PERIOD
(HIGH FLOW FORECAST):
 
...TABLE 2--EXCEEDANCE PROBABILITIES

                               Chance of Exceeding Stages
                                  at Specific Locations
                          Valid Period: 03/18/2024 - 06/16/2024
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Manistee River
Sherman              13.3   13.3   13.5   13.7   14.2   14.7   15.2
:Boardman River
Mayfield--Brown B     3.9    4.0    4.2    4.4    4.7    5.1    5.2
:Au Sable River
Red Oak               4.3    4.3    4.4    4.8    5.1    5.9    6.1
:Rifle River
Sterling              3.3    3.8    4.4    5.1    6.2    7.5    8.3
:Pine River
Rudyard               3.3    3.8    4.8    6.4    8.2    9.3   10.3
:Tobacco River
Beaverton             4.1    4.9    5.7    6.3    7.0    7.9    8.8
 
CURRENT FORECASTS SUGGEST PROBABILITIES OF EXCEEDING FLOOD STAGE ARE
LESS THAN 5 PERCENT EXCEPT FOR THE RIFLE RIVER NEAR STERLING...WHERE
THEE PROBABILITY OF EXCEEDING THE FLOOD STAGE OF 6 FEET IS AROUND
30 PERCENT.
 
THE LAST TABLE INDICATES THE CHANCE THAT A PARTICULAR RIVER LOCATION
COULD FALL BELOW THE LISTED STAGES IN THE SPECIFIED 90 DAY PERIOD
(LOW FLOW FORECAST):
 
...TABLE 3--NON-EXCEEDANCE PROBABILITIES...

                            Chance of Falling Below Stages
                                 at Specific Locations
                          Valid Period: 03/18/2024 - 06/16/2024
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Manistee River
Sherman              12.2   12.1   11.9   11.7   11.4   11.4   11.2
:Boardman River
Mayfield--Brown B     3.6    3.6    3.5    3.4    3.4    3.3    3.3
:Au Sable River
Red Oak               3.5    3.4    3.3    3.1    3.0    2.9    2.8
:Rifle River
Sterling              2.0    1.9    1.8    1.7    1.5    1.4    1.4
:Pine River
Rudyard               1.3    1.2    1.2    1.1    1.1    1.0    1.0
:Tobacco River
Beaverton             2.5    2.4    2.4    2.4    2.3    2.3    2.2

SPRING FLOOD OUTLOOKS ARE ROUTINELY ISSUED IN FEBRUARY AND MARCH IN
ORDER TO GIVE ADVANCE NOTICE OF POSSIBLE FLOODING. THE LONG RANGE
PROBABILISTIC OUTLOOKS GIVEN IN THE ABOVE TABLES CONTAIN FORECAST
VALUES THAT ARE CALCULATED USING MULTIPLE SEASON SCENARIOS FROM 30
OR MORE YEARS OF CLIMATOLOGICAL DATA...AND INCORPORATE CURRENT
RIVER LEVELS...SOIL MOISTURE CONDITIONS...SNOW DEPTH AND SNOW WATER
EQUIVALENT VALUES...AND BOTH 30 AND 90 DAY OUTLOOKS FOR TEMPERATURE
AND PRECIPITATION PROVIDED BY THE NOAA/NWS CLIMATE PREDICTION
CENTER.  ACTUAL RIVER CRESTS WILL DIFFER FROM THIS OUTLOOK IF
FUTURE CONDITIONS DIFFER SIGNIFICANTLY FROM FORECAST CONDITIONS...
OR IF ICE JAMS DEVELOP.
 
...CURRENT CONDITIONS...                                           

AN HISTORICALLY WARM WINTER IS THE DOMINANT FACTOR IN THE BELOW 
NORMAL SNOWMELT FLOOD PROBABILITIES ACROSS NORTHERN MICHIGAN THIS
SPRING...CONTRIBUTING TO A MINIMAL SNOWPACK.  AVERAGE TEMPERATURES
FOR THE WINTER SEASON (DECEMBER THROUGH FEBRUARY) WERE 6 TO 8 
DEGREES ABOVE NORMAL...WHICH WAS A RECORD WARMEST WINTER FOR ALL
OF THE MAJOR CLIMATOLOGICAL STATIONS ACROSS NORTHERN MICHIGAN 
(BY 1 TO 3 DEGREES ABOVE THE PREVIOUS RECORD).  THE WARM WEATHER
HAS CONTINUED THROUGH THE FIRST TWO WEEKS OF MARCH...WITH
DEPARTURES FROM NORMAL AVERAGE TEMPERATURES OF +13 TO +15 DEGREES.

AS A RESULT OF ALL OF THIS ANOMALOUS WARMTH...SNOWFALL THUS FAR
SINCE JULY 1 IS RUNNING ABOUT 50 TO 75 PERCENT OF NORMAL.  A
MAJORITY OF THAT SNOWFALL OCCURRED DURING THE PERIOD OF JANUARY
9-23 WHERE SOME LOCATIONS RECEIVED MORE THAN 50 PERCENT OF THEIR
SEASONAL TOTAL THUS FAR IN JUST THAT TWO WEEK PERIOD.  AS OF
MARCH 14...THE ONLY SNOW COVER WAS A MINIMAL AMOUNT REMAINING
AROUND THE WEST SIDE OF WHITEFISH BAY. 

PRECIPITATION DURING THE FALL MONTHS OF 2023 (SEPTEMBER THROUGH
NOVEMBER) WAS NEAR NORMAL ACROSS EASTERN UPPER AND NORTHWEST LOWER
MICHIGAN...TRENDING BELOW NORMAL (50 TO 75 PERCENT OF NORMAL) CLOSER
TO SAGINAW BAY. FOR THE WINTER PERIOD (DECEMBER THROUGH FEBRUARY)...
PRECIPITATION WAS 50 TO 75 PERCENT OF NORMAL ACROSS MOST OF NORTHWEST
LOWER MICHIGAN AND AREAS ADJACENT TO THE ST. MARY'S RIVER IN EASTERN
UPPER MICHIGAN...AND 75 TO 100 PERCENT OF NORMAL ELSEWHERE.  MARCH
HAS GOTTEN OFF TO A MUCH WETTER START...WITH A LARGE SWATH OF
PRECIPITATION AMOUNTS 200 TO 300 PERCENT OF NORMAL ENCOMPASSING MOST
OF NORTHERN LOWER MICHIGAN.

SOIL MOISTURE IS RUNNING BELOW NORMAL ACROSS EASTERN UPPER AND FAR
NORTHWEST LOWER MICHIGAN...ABOUT 20 TO 30 PERCENT OF NORMAL.  SOIL
MOISTURE IS NEAR NORMAL FOR MUCH OF NORTHEAST LOWER MICHIGAN.
CURRENT DROUGHT CONDITIONS BASED ON THE U.S. DROUGHT MONITOR FOR
MARCH 14 INDICATES MODERATE DROUGHT CONDITIONS ACROSS EASTERN UPPER
MICHIGAN AS WELL AS ACROSS MANISTEE COUNTY IN NORTHWEST LOWER
MICHIGAN...AND ABNORMALLY DRY CONDITIONS FOR PARTS OF THE REMAINDER
OF NORTHERN LOWER MICHIGAN.  HOWEVER RAINFALL OVER THE PAST 10 DAYS
HAS ALLEVIATED ANY DROUGHT CONDITIONS ALONG A AXIS FROM CADILLAC TO
GAYLORD TO ROGERS CITY.   

MOST GAUGING STATIONS ON AREA RIVERS ARE RUNNING AT MOSTLY NORMAL
STREAMFLOWS.
 
...WEATHER OUTLOOK...
THE CURRENT CLIMATOLOGICAL OUTLOOK FOR THE REMAINDER OF MARCH HAS
NO DISCERNIBLE TREND WITH REGARD TO TEMPERATURE (EQUAL PROBABILITIES
FOR ABOVE...NORMAL...AND BELOW NORMAL TEMPERATURES)...AND A HIGHER
PROBABILITY FOR ABOVE NORMAL PRECIPITATION.

THE OUTLOOK FOR THE SPRING (MARCH THROUGH MAY) INDICATES A 50 TO
60 PERCENT PROBABILITY FOR ABOVE NORMAL TEMPERATURES...AND NO
DISCERNIBLE TREND WITH REGARD TO PRECIPITATION (EQUAL PROBABILITIES
FOR ABOVE...NORMAL...AND BELOW NORMAL PRECIPITATION).
 
...ADDITIONAL INFORMATION...
THIS IS THE FINAL SPRING FLOOD OUTLOOK ISSUANCE FOR THIS YEAR.
LONG RANGE PROBABILISTIC OUTLOOKS SUCH AS THOSE GIVEN IN THE ABOVE
TABLES ARE ISSUED DURING THE LAST WEEK OF EACH MONTH THROUGHOUT THE
YEAR.
 
VISIT WATER.WEATHER.GOV/AHPS2/INDEX.PHP?WFO=APX (ALL LOWER CASE)
FOR MORE RIVER INFORMATION...INCLUDING GRAPHS OF THE PROBABILISTIC
INFORMATION GIVEN IN THE ABOVE TABLES...AS WELL AS THE LATEST
OBSERVED CONDITIONS ON NORTHERN MICHIGAN STREAMS.
 
$$

JPB