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FGUS73 KLOT 291856
ESFLOT
ILC007-011-031-037-063-075-089-091-097-099-105-111-141-197-201-
INC073-089-111-127-301800-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1250 PM CST FRI JAN 29 2010

...2010 SPRING FLOOD AND WATER RESOURCES OUTLOOK NUMBER 1...

THIS SPRING FLOOD AND WATER RESOURCES OUTLOOK IS FOR STREAMS WITHIN
THE DES PLAINES...FOX...LITTLE CALUMET...AND KANKAKEE RIVER BASINS
IN NORTHEAST ILLINOIS AND NORTHWEST INDIANA INCLUDING THE ILLINOIS
RIVER DOWN TO LA SALLE. THIS OUTLOOK ALSO INCLUDES STREAMS IN THE
ROCK RIVER BASIN INCLUDING THE PECATONICA AND KISHWAUKEE RIVERS AS
WELL AS THE ROCK RIVER FROM ROCKTON DOWN TO DIXON.

THESE OUTLOOKS ARE ISSUED EACH LATE WINTER AND EARLY SPRING IN
ADDITION TO THE 7 DAY RIVER FORECASTS THAT ARE ISSUED WHEN RIVER
FORECAST LOCATIONS ARE IN FLOOD OR ARE FORECAST TO RISE ABOVE FLOOD
STAGE.

...CURRENT SNOW COVER AND LIQUID WATER EQUIVALENT...
WARM TEMPERATURES LAST WEEKEND HAD MELTED MOST OF THE SNOW COVER
OVER NORTHERN ILLINOIS AND NORTHWEST INDIANA. HOWEVER...SOME SNOW
STILL REMAINS OVER PORTIONS OF THE UPPER ROCK...FOX...AND DES
PLAINES RIVER BASINS. ALTHOUGH MUCH OF THE SNOW HAD MELTED...THERE
STILL IS SIGNIFICANT GROUND ICE AND FROZEN WATER IN FIELDS WITHIN
THE WATERSHEDS. WATER EQUIVALENTS OF THE REMAINING SNOW AND GROUND
ICE WERE BETWEEN 1 AND 2 INCHES.

SOIL MOISTURE AND FROST DEPTH
SOIL MOISTURE REMAINS ABOVE NORMAL. FROST DEPTHS WERE REPORTED
BETWEEN 2 AND 6 INCHES.

...RIVER CONDITIONS...
STREAMFLOW REMAINS ABOVE NORMAL THROUGHOUT THE AREA. PORTIONS OF THE
KANKAKEE...ROCK...AND FOX RIVERS HAVE EXPERIENCED ICE JAM FLOODING
OVER THE PAST MONTH. AN ICE JAM REMAINS ON THE LOWER FOX RIVER
BETWEEN THE I-80 BRIDGE AND OTTAWA. COLDER TEMPERATURES OVER THE
LAST FEW DAYS HAVE RESULTED IN SOME NEW ICE FORMATION ON AREA
STREAMS. ICE JAMS AND ICE JAM FLOODING ARE POSSIBLE. WATER LEVELS
CAN RISES RAPIDLY WITH LITTLE OR NO WARNING IN THE VICINITY OF ICE
JAMS.

...WEATHER OUTLOOKS...
THE 8 TO 14 DAY OUTLOOK INDICATES ABOVE NORMAL TEMPERATURES AND
PRECIPITATION.

THE LATEST OUTLOOK FOR FEBRUARY INDICATES NORMAL PRECIPITATION
AND TEMPERATURES.

...FLOOD POTENTIAL SUMMARY...
THE FLOOD POTENTIAL IS ABOVE NORMAL FOR STREAMS WITHIN THE ROCK
RIVER BASIN. FLOOD POTENTIAL IS SLIGHTLY ABOVE NORMAL FOR PORTIONS
OF THE FOX...VERMILION...IROQUOIS...KANKAKEE...AND DES PLAINES
RIVERS. ELSEWHERE...FLOOD POTENTIAL IS NEAR NORMAL.

THIS SPRING OUTLOOK IS BASED ON HYDROLOGIC CONDITIONS INCLUDING THE
CURRENT SOIL MOISTURE...SNOWPACK...AND STREAMFLOW CONDITIONS AT THE
TIME OF ISSUANCE. IT SHOULD BE NOTED THAT HYDROLOGIC CONDITIONS CAN
CHANGE RAPIDLY DURING THE LATE WINTER AND EARLY SPRING.


LOCATION/FLOOD STAGE / DEPARTURE FROM NORMAL OF
                       REACHING FLOOD STAGE
---------------------------------------------------------------------
PECATONICA RIVER AT SHIRLAND/ 12 /        37% GREATER
ROCK RIVER AT ROCKTON         10 /        35% GREATER
ROCK RIVER AT LATHAM PARK     10 /        38% GREATER
KISHWAUKEE RIVER AT BELVIDERE  9 /        10% GREATER
S BR KISHWAUKEE RIVER DE KALB 10 /        NEAR NORMAL
KISHWAUKEE RIVER PERRYVILLE   12 /        25% GREATER
ROCK RIVER AT BYRON           13 /        34% GREATER

KANKAKEE RIVER DUNNS BRIDGE   10 /        NEAR NORMAL
KANKAKEE RIVER AT KOUTS       10 /        NEAR NORMAL
KANKAKEE RIVER AT SHELBY       9 /        13% GREATER
KANKAKEE RIVER AT MOMENCE      5 /        NEAR NORMAL
IROQUOIS RIVER AT RENSSELAER  12 /        NEAR NORMAL
IROQUOIS RIVER AT FORESMAN    18 /        7% GREATER
IROQUOIS RIVER AT IROQUOIS    18 /        11% GREATER
IROQUOIS RIVER AT CHEBANSE    16 /        NEAR NORMAL
KANKAKEE RIVER NR WILMINGTON 6.5 /        6% GREATER
DES PLAINES RIVER AT RUSSELL   7 /        12% GREATER
DES PLAINES RIVER AT GURNEE    7 /        10% GREATER
DES PLAINES RIVER DES PLAINES  5 /        9% GREATER
DES PLAINES RIVER AT RIVERSIDE 7 /        6% GREATER
FOX RIVER AT MONTGOMERY       13 /        13% GREATER
FOX RIVER AT DAYTON           12 /        9% GREATER
VERMILION RIVER AT PONTIAC    14 /        NEAR NORMAL
VERMILION RIVER AT LEONORE    16 /        7% GREATER

THORN CREEK AT THORNTON       10 /        NEAR NORMAL
LITTLE CALUMET RIVER MUNSTER  12 /        NEAR NORMAL

ILLINOIS RIVER AT MORRIS      16 /        NEAR NORMAL
ILLINOIS RIVER AT OTTAWA     463 /        NEAR NORMAL
ILLINOIS RIVER AT LA SALLE    20 /        12% GREATER


THE VALUES IN THE TABLE BELOW ARE VALID FEB 1 TO MAY 2 2010

IN THE TABLE BELOW...THE 90 THROUGH 10 PERCENT COLUMNS INDICATE
THE CHANCE THAT A LOCATION ON A RIVER COULD RISE ABOVE THE LISTED
STAGE LEVELS IN THE NEXT 90 DAYS.

FOR EXAMPLE: THE KANKAKEE RIVER AT DUNNS BRIDGE HAS A FLOOD STAGE OF
10 FEET. WITHIN THE NEXT 90 DAYS...THERE IS A 50 PERCENT CHANCE
THE RIVER WILL RISE ABOVE 9.5.

LOCATION        FS (FT)   90%  80%  70%  60%  50%  40%  30%  20%  10%
--------        -------   ---  ---  ---  ---  ---  ---  ---  ---  ---
KANKAKEE RIVER
 DUNNS BRIDGE    10.0     8.1  8.3  8.7  9.0  9.5  9.8 10.1 10.7 11.2
 KOUTS           11.0     9.3  9.4  9.8 10.1 10.7 10.9 11.2 11.9 12.3
 SHELBY           9.0     9.2  9.8 10.1 10.6 10.8 11.4 11.8 12.7 13.7
 MOMENCE          5.0     3.6  3.8  4.2  4.4  4.6  4.8  5.0  5.7  6.6
 WILMINGTON       6.5     3.5  4.1  4.6  4.9  5.1  5.6  5.8  6.1  6.9

IROQUOIS RIVER
 RENSSELAER      12.0     9.7 10.3 10.8 11.3 11.9 12.2 12.6 13.3 13.6
 FORESMAN        18.0    13.6 14.8 15.8 16.4 16.8 17.3 17.8 18.1 18.9
 IROQUOIS        18.0    15.0 16.8 18.1 19.4 20.5 21.2 22.0 22.6 23.3
 CHEBANSE        16.0     9.5 10.6 11.5 12.0 13.0 13.5 14.2 14.8 16.4

DES PLAINES RIVER
 RUSSELL          7.0     6.6  7.0  7.1  7.2  7.4  7.5  7.6  7.8  8.3
 GURNEE           7.0     5.0  5.4  5.9  6.1  6.6  6.9  7.3  7.7  8.5
 DES PLAINES      5.0     2.6  2.7  3.1  3.2  3.7  4.0  4.9  5.8  7.2
 RIVERSIDE        7.0     5.3  5.5  5.9  6.0  6.1  6.4  6.8  7.1  8.1

FOX RIVER
 ALGONQUIN        3.0
 MONTGOMERY      13.0    12.5 12.7 12.8 12.9 13.0 13.2 13.3 13.5 13.9
 DAYTON          12.0     9.0 10.1 10.6 10.7 10.9 11.5 12.0 12.7 14.1

VERMILION RIVER
 PONTIAC         14.0     6.8  7.9  8.9  9.6 10.1 11.1 12.0 12.7 14.3
 LEONORE         16.0    10.4 12.2 13.2 13.8 15.1 16.5 17.0 18.5 21.0

THORN CREEK
 THORNTON        10.0     6.5  7.6  7.8  8.3  8.6  8.9  9.3  9.7 10.6

LITTLE CALUMET RIVER
 MUNSTER         12.0     9.5 10.1 10.4 10.7 11.0 11.2 11.7 12.2 13.1
 SOUTH HOLLAND   16.5    10.9 11.8 12.0 12.4 12.5 12.8 13.2 14.1 14.5

ILLINOIS RIVER
 MORRIS          16.0     9.8 11.9 12.7 14.1 15.0 15.9 16.9 17.7 20.4
 OTTAWA          463.0    450.7 451.2 452.0 453.4 454.6 456.3 458.0
460.0 461.8
 LA SALLE        20.0    17.2 19.9 21.5 22.7 23.0 23.6 24.4 25.8 28.4

KISHWAUKEE RIVER
 BELVIDERE        9.0     5.4  6.0  6.6  7.2  7.7  8.4  8.9  9.1  9.9
 PERRYVILLE      12.0    10.3 10.9 11.4 12.2 12.7 13.2 13.8 14.3 14.9

SOUTH BRANCH KISHWAUKEE RIVER
 DE KALB         10.0     5.8  6.3  6.6  7.1  7.3  7.5  8.0  8.6  9.2

ROCK RIVER
 ROCKTON         10.0     8.0  8.4  9.5 10.4 10.9 11.4 12.2 13.1 14.9
 LATHAM PARK     10.0     7.8  8.1  9.1  9.9 10.3 10.9 11.5 12.4 14.0
 ROCKFORD         9.0     3.6  3.6  3.9  4.3  4.6  4.9  5.4  6.0  7.2
 BYRON           13.0    10.3 10.9 11.7 12.3 12.9 13.1 13.9 14.6 16.6

PECATONICA RIVER
 SHIRLAND        12.0    11.7 12.4 12.9 13.2 13.8 14.3 14.7 15.2 15.9

THE NATIONAL WEATHER SERVICE CHICAGO OFFICE IN ROMEOVILLE ISSUES LONG
RANGE AHPS OUTLOOKS FOR ALL RIVER FORECAST LOCATIONS. THIS PRODUCT IS
UPDATED MONTHLY AROUND MID-MONTH. THESE OUTLOOKS ARE ISSUED IN
ADDITION TO THE 5 DAY RIVER FORECASTS THAT ARE ISSUED WHEN RIVER
FORECAST LOCATIONS ARE IN FLOOD OR FORECAST TO RISE ABOVE FLOOD
STAGE.

THIS LONG-RANGE PROBABILISTIC OUTLOOK CONTAINS 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...AND 30 TO 90 DAY LONG-RANGE OUTLOOKS OF TEMPERATURE
AND PRECIPITATION.

BY PROVIDING THE COMPLETE RANGE OF PROBABILISTIC NUMBERS...THE LEVEL
OF RISK ASSOCIATED WITH LONG-RANGE PLANNING DECISIONS CAN BE
DETERMINED. THESE PROBABILISTIC FORECASTS ARE PART OF THE NATIONAL
WEATHER SERVICE ADVANCED HYDROLOGIC PREDICTION SERVICE.

VISIT OUR WEB PAGE AT WEATHER.GOV/CHICAGO FOR MORE WEATHER AND RIVER
INFORMATION INCLUDING GRAPHS OF PROBABILISTIC RIVER OUTLOOKS.


...FLOOD TERMINOLOGY...

THE TERM MINOR FLOODING IS USED TO INDICATE MINIMAL OR NO PROPERTY
DAMAGE. HOWEVER SOME PUBLIC INCONVENIENCE IS POSSIBLE.

MODERATE FLOODING IS USED TO INDICATE THE INUNDATION OF SECONDARY
ROADS. TRANSFER TO HIGHER ELEVATIONS MAY BE NECESSARY TO SAVE
PROPERTY. SOME EVACUATIONS MAY BE REQUIRED.

MAJOR FLOODING IS USED TO INDICATE EXTENSIVE INUNDATION AND PROPERTY
DAMAGE USUALLY CHARACTERIZED BY EVACUATION OF PEOPLE AND LIVESTOCK
AND CLOSURE OF BOTH PRIMARY AND SECONDARY ROADS.

VISIT OUR WEB PAGE AT WEATHER.GOV/CHICAGO FOR MORE WEATHER AND RIVER
INFORMATION INCLUDING GRAPHS OF PROBABILISTIC RIVER OUTLOOKS.

THE NEXT SPRING FLOOD OUTLOOK WILL BE ISSUED FRIDAY FEB 19 2010.

$$

WDM