Extended Streamflow Guidance
Issued by NWS
Issued by NWS
Versions:
1
666
FGUS63 KMSR 232032
ESGRCK
ROCK RIVER BASIN
LONG-RANGE PROBABILISTIC OUTLOOK
NATIONAL WEATHER SERVICE
NORTH CENTRAL RIVER FORECAST CENTER TWIN CITIES/CHANHASSEN MN
331 PM CDT THU APR 23 2026
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: 04/27/2026 - 07/26/2026
: 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
-------- ----- ----- ----- : ---- ---- ---- ---- ---- ----
:Rock River
WATW3 5.5 6.0 6.5 >95 9 >95 6 >95 5
:Crawfish River
MILW3 7.0 9.0 10.0 >95 16 5 8 <5 <5
:Rock River
JFFW3 10.0 11.0 13.0 >95 17 >95 14 <5 6
FATW3 16.0 17.0 18.0 >95 13 12 7 <5 <5
NVLW3 10.0 11.0 11.5 >95 31 >95 15 >95 14
AFTW3 9.0 11.1 12.2 >95 28 >95 13 19 7
:Turtle Creek
CLIW3 8.0 11.0 12.0 22 14 6 5 <5 <5
:Pecatonica River
DARW3 13.5 15.0 16.0 17 10 <5 <5 <5 <5
:East Branch Pecatonica River
BCHW3 11.0 14.0 16.0 27 16 9 8 <5 <5
:Pecatonica River
MTNW3 13.5 18.0 21.0 26 18 <5 6 <5 <5
FEEI2 13.0 14.0 16.0 26 16 16 14 <5 <5
:Sugar River
ALBW3 12.0 13.0 14.0 <5 <5 <5 <5 <5 <5
BROW3 5.0 8.0 10.0 32 21 16 11 <5 <5
:Pecatonica River
SIRI2 12.0 14.0 15.5 36 25 17 10 <5 <5
:Rock River
ROKI2 10.0 11.0 14.0 >95 19 >95 17 10 7
LATI2 9.0 11.0 13.5 >95 19 >95 14 10 6
RABI2 6.0 8.5 10.0 18 9 <5 <5 <5 <5
:Kishwaukee River
BVDI2 9.0 10.0 12.0 28 17 12 9 <5 <5
:South Branch Kishwaukee River
DEKI2 10.0 11.0 12.5 14 10 5 <5 <5 <5
:Kishwaukee River
PRYI2 12.0 18.0 22.0 42 28 <5 <5 <5 <5
:Rock River
BYRI2 13.0 14.0 16.0 32 20 27 17 12 6
DXRI2 16.0 18.0 20.0 26 15 10 7 <5 <5
CMOI2 12.5 15.5 18.0 38 23 12 10 <5 <5
JOSI2 12.0 14.0 16.5 >95 44 >95 30 30 19
:Green River
GENI2 15.0 16.5 18.0 24 18 9 8 <5 <5
:Rock River
MLII2 12.0 13.0 14.0 >95 41 68 28 34 22
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...
.B MSR 0427 Z DH12 /DC2604232031/DVD90/HGVFZXT/HGVFZX9/HGVFZXH
.B1 /HGVFZX5/HGVFZXG/HGVFZX1/HGVFZXF
:
: Chance of Exceeding Stages (ft) at Specific Locations
: Valid Period: 04/27/2026 - 07/26/2026
:
: 95% 90% 75% 50% 25% 10% 5%
: --- --- --- --- --- --- ---
:Rock River
WATW3 6.8/ 6.8/ 6.8/ 6.8/ 6.8/ 6.8/ 6.8
:Crawfish River
MILW3 7.6/ 7.6/ 7.6/ 7.6/ 7.6/ 8.1/ 9.6
:Rock River
JFFW3 12.8/ 12.8/ 12.8/ 12.8/ 12.8/ 12.8/ 12.9
FATW3 16.9/ 16.9/ 16.9/ 16.9/ 16.9/ 17.1/ 17.8
NVLW3 13.0/ 13.0/ 13.0/ 13.0/ 13.0/ 13.1/ 13.9
AFTW3 12.1/ 12.1/ 12.1/ 12.1/ 12.1/ 12.5/ 13.2
:Turtle Creek
CLIW3 4.5/ 4.5/ 4.7/ 5.7/ 7.9/ 10.0/ 11.5
:Pecatonica River
DARW3 5.0/ 5.0/ 5.5/ 7.2/ 11.0/ 14.3/ 14.9
:East Branch Pecatonica River
BCHW3 6.6/ 6.6/ 6.9/ 9.3/ 11.3/ 13.9/ 15.3
:Pecatonica River
MTNW3 9.7/ 9.7/ 9.7/ 9.8/ 13.7/ 15.8/ 17.7
FEEI2 10.6/ 10.6/ 10.6/ 11.3/ 13.1/ 14.3/ 15.6
:Sugar River
ALBW3 5.3/ 5.3/ 5.7/ 7.1/ 9.0/ 11.2/ 11.8
BROW3 2.2/ 2.2/ 2.7/ 3.9/ 6.1/ 8.9/ 9.4
:Pecatonica River
SIRI2 11.5/ 11.5/ 11.5/ 11.5/ 12.9/ 14.5/ 14.8
:Rock River
ROKI2 11.8/ 11.8/ 11.8/ 11.8/ 12.0/ 14.1/ 15.0
LATI2 11.1/ 11.1/ 11.1/ 11.1/ 11.3/ 13.5/ 14.5
RABI2 5.0/ 5.0/ 5.0/ 5.0/ 5.3/ 6.7/ 7.5
:Kishwaukee River
BVDI2 4.1/ 4.1/ 5.7/ 7.1/ 9.4/ 10.2/ 11.3
:South Branch Kishwaukee River
DEKI2 4.1/ 4.6/ 5.5/ 7.3/ 8.9/ 10.5/ 11.1
:Kishwaukee River
PRYI2 7.9/ 8.0/ 9.1/ 11.0/ 13.2/ 15.8/ 16.6
:Rock River
BYRI2 12.6/ 12.6/ 12.6/ 12.6/ 14.4/ 16.2/ 16.9
DXRI2 14.1/ 14.1/ 14.1/ 14.1/ 16.1/ 18.3/ 19.4
CMOI2 11.9/ 11.9/ 11.9/ 11.9/ 14.0/ 16.2/ 17.7
JOSI2 14.6/ 14.6/ 14.7/ 14.7/ 17.2/ 19.2/ 20.3
:Green River
GENI2 6.5/ 6.5/ 8.2/ 11.4/ 14.8/ 16.0/ 17.8
:Rock River
MLII2 13.0/ 13.0/ 13.0/ 13.1/ 14.9/ 16.6/ 18.4
.END
IN TABLE 3 BELOW...THE 95 THROUGH 5 PERCENT COLUMNS INDICATE THE PROBABILITY
OF FALLING BELOW THE LISTED FLOW LEVELS (KCFS) FOR THE VALID TIME PERIOD.
:...TABLE 3--NONEXCEEDANCE PROBABILITIES...
.B MSR 0427 Z DH12 /DC2604232031/DVD90/QIVFZNT/QIVFZN9/QIVFZNH
.B1 /QIVFZN5/QIVFZNG/QIVFZN1/QIVFZNF
:
: Chance of Falling Below Flows (kcfs) at Specific Locations
: Valid Period: 04/27/2026 - 07/26/2026
:
: 95% 90% 75% 50% 25% 10% 5%
: --- --- --- --- --- --- ---
:Rock River
WATW3 0.6/ 0.5/ 0.4/ 0.3/ 0.2/ 0.2/ 0.2
:Crawfish River
MILW3 0.3/ 0.3/ 0.2/ 0.1/ 0.1/ 0.1/ 0.1
:Rock River
JFFW3 1.1/ 0.9/ 0.6/ 0.5/ 0.4/ 0.3/ 0.3
FATW3 1.4/ 1.2/ 0.8/ 0.6/ 0.5/ 0.4/ 0.4
AFTW3 3.1/ 2.9/ 1.5/ 1.2/ 1.0/ 0.9/ 0.8
:Turtle Creek
CLIW3 0.1/ 0.1/ 0.1/ 0.1/ 0.1/ 0.1/ 0.1
:Pecatonica River
DARW3 0.3/ 0.3/ 0.2/ 0.2/ 0.2/ 0.2/ 0.2
:East Branch Pecatonica River
BCHW3 0.2/ 0.2/ 0.2/ 0.1/ 0.1/ 0.1/ 0.1
:Pecatonica River
MTNW3 0.9/ 0.9/ 0.7/ 0.6/ 0.6/ 0.6/ 0.5
FEEI2 1.2/ 1.2/ 1.0/ 0.9/ 0.8/ 0.7/ 0.7
:Sugar River
ALBW3 0.3/ 0.3/ 0.3/ 0.3/ 0.2/ 0.2/ 0.2
BROW3 0.4/ 0.4/ 0.3/ 0.3/ 0.3/ 0.2/ 0.2
:Pecatonica River
SIRI2 2.1/ 2.0/ 1.7/ 1.5/ 1.3/ 1.2/ 1.2
:Rock River
ROKI2 5.5/ 5.2/ 3.7/ 3.0/ 2.6/ 2.4/ 2.2
LATI2 5.6/ 5.2/ 3.7/ 3.0/ 2.7/ 2.5/ 2.3
RABI2 5.6/ 5.3/ 3.8/ 3.1/ 2.7/ 2.5/ 2.3
:Kishwaukee River
BVDI2 0.4/ 0.4/ 0.3/ 0.2/ 0.2/ 0.1/ 0.1
:South Branch Kishwaukee River
DEKI2 0.0/ 0.0/ 0.0/ 0.0/ 0.0/ 0.0/ 0.0
:Kishwaukee River
PRYI2 0.8/ 0.7/ 0.6/ 0.4/ 0.4/ 0.3/ 0.3
:Rock River
BYRI2 6.5/ 6.4/ 4.7/ 3.8/ 3.3/ 2.9/ 2.7
DXRI2 7.0/ 6.8/ 5.1/ 4.1/ 3.6/ 3.2/ 3.0
CMOI2 7.1/ 7.0/ 5.2/ 4.2/ 3.6/ 3.3/ 3.1
JOSI2 7.7/ 7.4/ 5.6/ 4.6/ 4.0/ 3.6/ 3.3
:Green River
GENI2 0.5/ 0.5/ 0.4/ 0.3/ 0.2/ 0.2/ 0.2
:Rock River
MLII2 8.7/ 8.4/ 6.4/ 5.1/ 4.5/ 4.1/ 3.6
.END
:Long-range probabilistic outlooks are issued near the end of
:the month throughout the year.
$$