Flood Potential Outlook
Issued by NWS Great Falls, MT

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FGUS75 KTFX 051042
ESFTFX
121042-
HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
342 AM MST THU MAR 5 2015


...Montana Spring Flood and Water Resources Outlook...

...The potential for spring flooding for Montana east and west of the
Continental Divide during spring of 2015 is near to below normal...

Overall, mountain snowpack is near average. Snowpack over the plains
is shallow. More significant frozen ground conditions are primarily
limited to northeast and eastern Montana. Some frost reformed in
areas of central Montana with recent cold weather. Precipitation
during the summer and fall of 2014 provided for moist antecedent soil
conditions. With a near average snowpack, and generally open, albeit
moist, soils, the chance of widespread significant flooding either in
the mountainous areas or on the plains is unlikely. Having a below
normal risk for flooding does not rule out the possibility or even
likelihood of flooding. Areas having a less than normal risk for
flooding can still be projected to flood, albeit at a diminished risk
as compared to normal.

Some minor ice jam flooding has already occurred. High water due to
ice formation has been reported along reaches of the Jefferson, Two
Medicine, and Clarks Fork of the Yellowstone Rivers in Montana. More
ice jam flooding is possible east of the Continental Divide over the
next 2 to 4 weeks as spring break-up occurs.

CHANCES FOR MAJOR FLOODING
Based on the snowpack as of March 2 in the mountains of Montana and
the snow cover over the plains...
* A 10 to 15 percent chance of major flooding on the Shields River
near Livingston.
* All other sites east and west of the Continental Divide have a less
than 10 percent chance of major flooding due to snowmelt.

CHANCES FOR MODERATE FLOODING
Based on the current snowpack in the mountains of Montana and the
current snow cover over the plains, outlooks show...
* A 15 to 20 percent chance of moderate flooding on the Shields River
near Livingston
* A 10 to 15 percent chance of moderate flooding on Beaver Creek near
Hinsdale
* A 15 to 20 percent chance of moderate flooding on the Flathead at
Columbia Falls
* All other sites east and west of the Continental Divide have a less
than 10 percent chance of moderate flooding due to snowmelt.

CHANCES FOR MINOR FLOODING
Based on the current snowpack in the mountains of Montana and the
current snow cover over the plains, outlooks show
* A 10 to 15 percent chance of minor flooding on Big Hole River near
Melrose
* A 10 to 15 percent chance of minor flooding on Gallatin River near
Gallatin Gateway
* A 10 to 15 percent chance of minor flooding on Gallatin River near
Logan
* A 15 to 20 percent chance of minor flooding on Clear Creek near
Chinook
* A 15 to 20 percent chance of minor flooding on Beaver Creek near
Hinsdale
* A 20 to 25 percent chance of minor flooding on the Shields River
near Livingston.
* A 25 to 30 percent chance of minor flooding on the Clarks Fork of
the Yellowstone near Belfry.
* A 25 to 30 percent chance of minor flooding on the Clarks Fork of
the Yellowstone near Edgar.
* A 45 to 50 percent chance of minor flooding on the Flathead at
Columbia Falls.
* Most of the other sites east and west of the Continental Divide
have a less than 10 percent chance of minor flooding due to snowmelt.

CURRENT RIVER CONDITIONS...
With recent warm temperatures, many Montana streams and rivers have
opened, though some, particularly in northern and eastern Montana,
are still in ice. Of those rivers that are open, streams west of the
Continental Divide are mostly well above their long term median,
while streams east of the Divide are mostly near to above their long
term median.

CURRENT SOIL CONDITIONS...
Soils are wetter than normal across Montana. Frost depth reports
indicate soil is mostly unfrozen across western, southern, and
portions of central Montana. In northern and eastern Montana, frost
depth ranges from a few inches to over 2 feet in depth.

SOIL TEMPERATURE /DEGREES F/ AT LISTED DEPTH
                ELEV   2IN   4IN  6IN  8IN  12IN  20IN  30IN  40IN
 ALBERTON NR   6150          33       34         35         35
 BOZEMAN EXPST 4774    29    31       34         35
 BOZEMAN 12SE  6860                   33         34         35
 BRUSETT 4SE   2643    18    17       16         16         18
 CAMERON 15SW  8800          32       32         32         34
 COOKE CITY NR 8700          32       32         33          M
 CONRAD SCAN   3706    31    29       30         32         35
 FLATTOP MTN   6300                   34
 FROID 5S      2165    23             22
 GREAT FALLS   3776          31  32        33         34
 HAVRE SCAN    2710    30    28       28         33         36
 HELENA        3668          40       40
 JORDAN SCAN   2820    26    26       26         32          M
 LAKEVIEW NR   7400          31       32         28         34
 LAKEVIEW 15NW 7800          32       33         34         35
 LINCOLN 11SE  7020          32       33         35
 LINDSAY SCAN  2680    24    24       24         31         34
 LOOKOUT PASS  5140           M       34         34          M
 MANY GLACIER  4900                   33
 MAXVILLE NR   7210          33       34         34         35
 MOCCASIN SCAN 4256    31    32       33         35         37
 MT LOCKHART   6400          33       33         34         34
 NEIHART 12SE  8100          32       32         33         33
 POPLAR 13NE   2085    22    18       16         22         28
 SIDNEY 6NW    2250    26             22
 SIDNEY 8SW    1916    24             23
 SIDNEY SCAN   2274    21    20       22         28          M
 THREE FKS SCN 4775    32    31       30         35         38
 TIBER DAM SCN 3225    32    28       27         32         35
 W YELLOWSTONE 6700          32       32         33         34
 W YELLOWST SO 8150          33       32         34         35
 WHITE SS 13SE 7600          31       32         32         34

GROUND TEMPERATURE /DEGREES F/ AT THE SURFACE AND 18 INCHES DEEP AT
MONTANA DEPARTMENT OF TRANSPORTATION SITES

               ELEV  SURFACE                  18IN
 ABERDEEN HILL 4101    26                      28
 ALZADA DOT    4327    24                      28
 ARROW CREEK   3956    43                      41
 AVON NORTH    5085    41                      41
 BEARSMOUTH    3901    50                      33
 BEAVER HILL   2551    23                      24
 BIDDLE DOT    3418    33                      33
 BIG HOLE PASS 7400    37                      36
 BOULDER PASS  5600    38                      27
 BOWMANS CORNR 4301    34                      29
 BOZEMAN PASS  5748    40                      28
 BULL MOUNTAIN 3898    40                      31
 COMERSTOWN    2099    14                      15
 COW CREEK     2500    25                      23
 CRYSTAL CREEK 3030    36                      32
 DEEP CREEK    5870    30                      26
 DEARBORN      3500    47                      34
 DENTON DOT    3557    42                      31
 E LIVINGSTON  4555    41                      32
 EKALAKA DOT   3687    23                      26
 ESSEX DOT     3875    25                      29
 GARRISON DOT  4327    43                      32
 GEORGETOWN LK 6339    39                      28
 GEYSER DOT    4138    39                      28
 GOVERNMENT HL 3165    31                      28
 GREENOUGH HL  4070    42                      31
 HAYS DOT      3697     0                      26
 HELMVILLE DOT 4199    43                      32
 HILLSIDE DOT  2998    28                      28
 HYSHAM HILLS  3549    36                      33
 INGOMAR DOT   3018    32                      30
 INVERNESS     3300    39                       M
 JUDITH GAP    4677    38                      27
 KARST DOT     5698    35                      30
 LAME DEER     4327    22                      31
 LEWISTOWN DVD 4622    26                      23
 LINDSAY DIV   3198    24                      24
 LOMA DOT      2557    42                      34
 LOOKOUT PASS  4540    44                      32
 MACDONALD PSS 6320    22                      21
 MALTA SOUTH   3122    35                      27
 MCDONALDS DOT 2401    23                      18
 MONARCH CANYN 5218    37                      27
 MONIDA PASS   6824    33                      27
 NAVAHO DOT    2570    17                      17
 NINEMILE DOT  4301    39                      32
 NORRIS HILL   5695    37                      37
 PENDROY DOT   4199    39                      25
 RAYNOLDS PASS 6778    43                      27
 REEDPOINT DOT 3890    41                      34
 ROGERS PASS   5406    28                      27
 ROSCOE HILL   5337    39                      25
 SACO DOT      2177    33                      34
 SIEBEN DOT    4040    39                      23
 SIOUX PASS    2480    22                      22
 SWAN LAKE     3567    41                      32
 SWEENEY CREEK 2598    36                      31
 SWEET GRASS   3690    39                      25
 TROUT CREEK   2384    46                      34
 TWO MEDICINE  4920    33                      26
 US2 STATELINE 2099    28                      18
 YAAK HILL     2201    46                      46
 YELLOWSTONE B 3194    39                      33


SOIL MOISTURE /VOLUMETRIC SOIL MOISTURE IN PERCENT/ AT LISTED DEPTH
Soil moisture is in units of percent volumetric soil moisture. Field
capacity of silt loam and clay loam soils is approximately 35 percent
of volumetric soil moisture. Values at or near zero may be erroneous.

                      2IN   4IN  6IN  8IN  12IN  20IN  30IN  40IN
 ALBERTON NR  6150           21        29          8          11
 BOZEMAN 12SE  6860                    18         41          48
 BRUSETT 4SE   2643     7     8         5          5           5
 CAMERON 15SW  8800           M        39         38          41
 CONRAD SCAN   3706    21    21        19         34          36
 COOKE CITY NR 8700          13         0          8           M
 FLATTOP MTN   6300               36
 HAVRE SCAN    2710     9    12        21         27          25
 JORDAN SCAN   2820    13    16        21         23          14
 LAKEVIEW NEAR 7400           8         6         34          26
 LAKEVIEW 15NW 7800          29        18         28          16
 LINCOLN 11SE  7020          21        21         19           8
 LINDSAY SCAN  2860     7     5         8          6          13
 LOOKOUT PASS  5140           M        39         34
 MANY GLACIER  4900                    10
 MAXVILLE NR   7210          11         8          0          14
 MOCCASIN SCAN 4256    15    19        30         22          13
 MT LOCKHART   6400          36        36         34
 NEIHART 12SE  8100          29        32         29          33
 POPLAR 13NE   2085     7     8         7         14          11
 SIDNEY SCAN   2274     9    10        15         14           M
 THREE FKS SCN 4775    10    17        28         38           7
 TIBER DAM SCN 3225    15    20        19          6           4
 W YELLOWSTONE 6700           8         4          3           0
 W YELLOWST SO 8150          20        22         24          29
 WHITE SS 13SE 7600           1         4         11          24

CURRENT SNOW CONDITIONS...
As of March 2, for individual basins, the Natural Resources
Conservation Service, NRCS, is reporting conditions in Montana
ranging from near to below normal. More than half the major
watersheds, including Flathead, Sun/Teton/Marias, Bitterroot, Upper
Clark Fork, Missouri Mainstem, Smith/Judith/Musselshell, Jefferson,
Gallatin, and Upper Yellowstone are reporting snow water equivalent
of 90 to 115 percent of median. The Madison, and St. Mary/Milk are at
80 percent of normal. The Lower Clark Fork is at 69 percent of
normal, and the Kootenai is at 62 percent of normal. Snow depths
throughout the eastern plains of Montana range from 0 to 2 inches
with the exception of the far northeast corner of the state where
isolated areas have snow up to 8 inches deep. Snow water equivalents,
SWE, generally vary from 0 to 1 inch with isolated areas of far
northeast Montana having a SWE of 2 to 4 inches. Southern
Saskatchewan shows conditions similar to northeast Montana. By early
March, Montana is approximately 80 percent of the way through the
main snowfall period. There are still four to six weeks remaining
until the seasonal snowpack peak is reached.

Below are conditions as of March 2, 2015 for some individual SNOTEL
sites for basins in Montana. The information provided for each site
includes site elevation...current snow water equivalent, median SWE
for the date, median peak SWE, average date of the median peak SWE,
current SWE as a percent of median, current SWE as a percent of the
median peak, current snow depth and the current snow density.
Additionally, a basin-wide percent of average SWE is provided. This
is an abbreviated list...only those sites with the maximum percent
SWE...the median percent SWE and the minimum percent SWE for each
basin are provided. The list is sorted by major river basin.

SNOTEL SITE      ELEV  CURR   MED   MED  MED PK  PCT  PCT SNOW   SNOW
                        SWE   SWE  PEAK   DATE   MED PEAK DPTH  DNSTY
KOOTENAI RIVER BASIN
  Stahl Peak     6030  24.2  27.7  36.7   7-May   87   66   68    36
  Garver Creek   4250   5.6   8.1   9.2  28-Mar   69   61   21    27
  Hand Creek     5035   6.6   9.7  11.1  31-Mar   68   59   19    35
  Bear Mountain  5400  21.5  48.9  55.7  20-Apr   44   39   58    37
Basin Index                                       62   52

FLATHEAD RIVER BASIN
  Moss Peak      6780  34.6  28.4  39.1  11-May  122   88   98    35
  Bisson Creek   4920   8.0   8.5  10.0   5-Apr   94   80   26    31
  Many Glacier   4900   4.3  11.5  12.6  30-Mar   37   34   17    25
Basin Index                                       97   77

UPPER CLARK FORK RIVER BASIN
  Warm Springs   7800  19.7  15.0  21.8  10-May  131   90   66    30
  N Fk Elk Creek 6250  10.1   9.0  10.8   6-Apr  112   94   35    29
  Combination    5600   2.4   4.1   4.5  25-Mar   59   53   12    20
Basin Index                                      108   83

BITTERROOT RIVER BASIN
  Saddle Mtn.    7940  22.5  19.3  24.0  17-Apr  117   94   69    33
  Skalkaho Summt 7250  17.3  17.7  22.2  10-Apr   98   78   54    32
  Twelvemile Ck  5600   8.6  13.9  14.9  17-Mar   62   58   36    24
Basin Index                                       96   81

LOWER CLARK FORK RIVER BASIN
  Stuart Mtn     7400  28.8  26.1  31.2   7-Apr  110   92   86    33
  Hoodoo Basin   6050  24.4  32.7  40.1  18-Apr   75   61   74    33
  Humboldt Gulch 4250   5.8   9.8  10.1  23-Feb   59   57   22    26
  Lookout        5140   9.7  24.8  26.6  27-Mar   39   36   32    30
Basin Index                                       69   60

JEFFERSON RIVER BASIN
  Frohner Meadow 6480   7.3   5.9   7.6  11-Apr  124   96   28    26
  Calvert Creek  6430   7.4   6.9   7.5  24-Mar  107   99   25    30
  Lemhi Ridge    8100   8.8   8.2  10.6  14-Apr  107   83   34    26
  Lakeview Ridge 7400   4.2   8.6  10.8  10-Apr   49   39   17    25
Basin Index                                       97   72

MADISON RIVER BASIN
  Albro Lake     8300  12.6  13.9  20.0  23-Apr   91   63   47    27
  Black Bear     8170  23.8  29.9  37.4  30-Apr   80   64   68    35
  Lower Twin     7900   8.5  13.2  19.3  15-May   64   44   46    18
Basin Index                                       80   60

GALLATIN RIVER BASIN
  Brackett Creek 7320  20.5  14.7  20.8  15-Apr  139   99   60    34
  Lick Creek     6860   7.6   8.2  11.5   5-Apr   93   66   30    25
  Carrot Basin   9000  17.1  20.7  28.9   7-May   83   59   56    31
Basin Index                                       99   71

MISSOURI HEADWATERS
  Brackett Creek 7320  20.5  14.7  20.8  15-Apr  139   99   60    34
  Lick Creek     6860   7.6   8.2  11.5   5-Apr   93   66   30    25
  Lakeview Ridge 7400   4.2   8.6  10.8  10-Apr   49   39   17    25
Basin Index                                       94   70

HEADWATERS MISSOURI MAINSTEM
  Frohner Meadow 6480   7.3   5.9   7.6  11-Apr  124   96   28    26
  Nevada Ridge   7020  12.8  11.2  14.3   6-Apr  114   90   43    30
  Boulder Mtn    7950  14.6  15.7  21.1   4-May   93   69   53    28
Basin Index                                      107   79

SMITH, JUDITH, AND MUSSELSHELL RIVER BASINS
  Deadman Creek  6450  10.6   8.1   9.7   2-Apr  131  109   34    31
  Stringer Creek 6550  10.4   8.8  10.5   6-Apr  118   99   42    25
  Porcupine      6500   3.3   5.3   6.0   9-Apr   62   55   14    24
Basin Index                                      113   85

SUN, TETON AND MARIAS RIVER BASINS
  Badger Pass    6900  26.5  24.1  31.3  13-Apr  110   85   74    36
  Wood Creek     5960   6.2   7.6   8.6  11-Apr   82   72   26    24
  Dupuyer Creek  5750   3.4   7.1   9.2  11-Apr   48   37   23    15
Basin Index                                       92   74

MISSOURI MAINSTEM RIVER BASIN
  Deadman Creek  6450  10.6   8.1   9.7   2-Apr  131  109   34    31
  Daisy Peak     7600   8.1   7.2  11.1  20-Apr  112   73   32    25
  Dupuyer Creek  5750   3.4   7.1   9.2  11-Apr   48   37   23    15
Basin Index                                      106   82

ST. MARY AND MILK RIVER BASINS
  Rocky Boy      4700   5.0   4.1   4.4  12-Mar  122  114   23    22
  Flattop Mtn.   6300  30.5  34.1  43.4  13-Apr   89   70   90    34
  Many Glacier   4900   4.3  11.5  12.6  30-Mar   37   34   17    25
Basin Index                                       80   66

UPPER YELLOWSTONE RIVER BASIN
  Brackett Crk   7320  20.5  14.7  20.8  15-Apr  139   99   60    34
  Sylvan Road    7120  10.2   9.6  11.1   2-Apr  106   92   35    29
  Porcupine      6500   3.3   5.3   6.0   9-Apr   62   55   14    24
Basin Index                                      107   79

LOWER YELLOWSTONE RIVER BASIN
  Bear Trap Mdw  8200   7.5   4.5   5.2  24-Mar  167  144   35    21
  Grave Springs  8550   7.7   7.0   9.7  18-Apr  110   79   35    22
  St. Lawrence   8620   4.0   5.3   6.9   8-Apr   75   58   24    17
Basin Index                                      105   75

This outlook contains a generalized summary of snowmelt flood
potential. Above normal future snow accumulations combined with heavy
rains and rapid melt will increase the current flood potential. Below
normal future precipitation and gradual or intermittent freezing and
thawing will decrease the magnitude of the current assessment.
Additionally, when the remaining frozen rivers and streams thaw, ice
jams may develop causing higher river levels and possible flooding.
Ice jam flooding will continue to be a threat for some locations east
of the continental divide into April.

Projections of river stages are based on current observed states of
streamflow, soil moisture, and snow pack, coupled with future
precipitation and temperature patterns and anticipated operational
hydrologic changes such as reservoir releases and canal diversions.
Outlooks are provided for long-range projections...weeks to months...
based on climatological patterns of precipitation and temperature.
Forecasts are provided for short-term projections...days...based on
future forecasted patterns of precipitation and temperature. The
uncertainty of these products varies from season to season and site
to site. In recent years, outlook crests have been above the observed
crest about as often as they have been below the observed crest. The
uncertainty of forecasts tends to be less than the uncertainty of
outlooks due to their shorter lead time. Users of these products are
encouraged to contact their nearest National Weather Service Forecast
Office for continued updates of meteorological conditions which can
have significant impacts on flood planning and flood fighting
activities.

Outlook numbers for locations not represented in NWS AHPS products
are not being issued with this product. For additional quantitative
information, please refer to AHPS products for probabilistic
forecasts of potential flooding. Refer to flood forecasts, if any are
currently issued, for information about ongoing or anticipated
flooding.

This is the last scheduled Spring Outlook of the season. If
significant changes occur subsequent to this product, additional
outlooks can be released to address needs.

$$

.END/LOSS




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