Drought Information Statement
Issued by NWS Great Falls, MT
AXUS75 KTFX 222152
DROUGHT INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
352 PM MDT FRI MAR 22 2013
...Drought Conditions Generally Hold Steady Across Montana...
A ridge of high pressure aloft along the west coast dominated the
weather across much of Montana during February producing warmer and
drier conditions statewide. Typically, the high pressure ridge is
centered slightly further east and is not as strong as during
February 2013. Under the influence of this high pressure ridge,
temperatures averaged near to above normal across the state.
Exceptions to this were south central and southwest which were
cooler than normal. Average temperature anomalies ranged from 1.6
degrees below normal at Mystic Lake to nearly 8 degrees above normal
at Miles City. This was the 6th consecutive month with above normal
temperatures for the state, and the 10th of the past twelve months
with above normal temperatures.
The monthly accumulated precipitation across Montana was mostly below
normal. The exception was an area from near Cut Bank through Great
Falls which received above normal precipitation. The wettest areas
were portions west of the divide and the mountains. February was the
7th in the past 12 months to have below normal precipitation. For
the past 12 months, there is a 1.42 inch negative anomaly for the
state precipitation. Snowfall was on the light side for February.
Outside of isolated areas recording slightly above normal snowfall,
most areas were below to much below normal. The statewide average of
3.8 inches was 4.3 inches below average. February 2013 recorded the
lowest average snowfall since February 2005.
For a statewide average, winds were above average in February.
Portions of the west and extreme east had below average winds. This
is the second month in a row to record above average winds.
As of March 19, the portion of Montana in some stage of drought on
the National Drought Monitor was just over 29 percent /29.17/, up
slightly from February 19. The portion of Montana in the D3 Extreme
Drought category remains under 4 percent /3.48/, and over 15
percent /15.35/ is in the D2 Severe Drought category. That portion
of the state in the D1 Moderate Drought category is down to less
than 11 percent /10.34/, and just under 12 percent /11.89/ of
Montana is in the D0 Abnormally Dry category.
The Drought Outlook released March 19 shows no drought development
expected through the end of June 2013 across those portions of
northern and central Montana that are currently void of drought
conditions on the National Drought Monitor. The Drought Outlook also
indicates the far southeast corner of the state should see
improvement during the March through June period. Across southwest
and south central Montana, the Drought Outlook indicates the drought
will be ongoing with some slight improvement. This assessment is
based on current near normal snowpack in the mountains, good
reservoir storage and a climate outlook that is not indicating
better chances for drier than normal precipitation amounts for the
April through June period. There continues to be concern about the
lack of low elevation snowpack and below normal soil moisture. This
area will be monitored closely as we move through our spring months.
SUMMARY OF IMPACTS...
STATE AND LOCAL ACTIONS...
The Montana Governor`s Drought Advisory Committee has been in recess
through the winter season, and will resume their public meetings
April 18 2013. The technical sub-committee continues to meet monthly
for drought and water supply assessment of Montana counties.
SOIL MOISTURE CONDITIONS...
At the end of February, soil moisture over western Montana was noted
to be above normal while areas in central, south central and
southeast Montana were noted to be below normal. Frost depth across
the state generally ranges from 2 to 6 inches with some areas
reporting no soil frost.
Supplemental feeding continues and is not uncommon as Montana moves
into early spring. At the end of February, 98 percent of cattle and
sheep were receiving supplemental feed /91 percent last year/.
Livestock grazing areas were 45 percent open /63 percent last year/,
22 percent difficult /18 percent last year/ and 33 percent closed
due to drought and/or snow /19 percent last year/.
As of the end of February, topsoil moisture ranked as short to very
short was 35 percent /53 percent last year/. Subsoil moisture short
to very short was 60 percent /52 percent last year/. At the end of
February, protectiveness of crops from snow cover is above last year
with 18 percent good to excellent /2 percent last year/. Winter
wheat condition was above last year with 38 percent good to
excellent /24 percent last year/. Wind and freeze damage remain low
with 95 percent none to light /65 percent last year/. Freeze and
drought damage remains low at 7 percent /14 percent last year/. With
the benefit of some snow cover, only 7 percent of the crop has
suffered moderate to heavy freeze and drought damage.
February across Montana was generally warmer and drier than normal.
Temperatures for February 2013 were the 24th warmest of 119 years of
record while precipitation for the state was the 12th driest. During
the first three weeks of March, the northeast corner and the far
northwest corner of Montana have received above to much above normal
precipitation. The remainder of the state has reported below normal
precipitation for the month to date, with southwest, central and
south central reporting large areas with much below normal
The April outlook for Montana released March 21 indicates a 40 to 50
percent chance temperatures will be below normal northwest, with a
33 to 40 percent chance temperatures will be below normal southwest
to northeast. South central through eastern Montana has equal
chances temperatures will be above, below or near normal for the
month. For precipitation, the April outlook indicates equal chances
for above, below or near normal precipitation statewide.
As we move from late spring into mid-summer, the outlook for the
three months of May through July show equal chances for above, below
or near normal temperatures for all except far south central and
southeast Montana where there is a 33 to 40 percent chance
temperatures will be above normal. The precipitation outlook
continues to show no trends toward wetter or drier conditions
indicating equal chances for above, below or near normal
precipitation across all of Montana.
In an update released March 7, the National Weather Service Climate
Prediction Center with the International Research Institute for
Climate and Society stated that El Nino Southern Oscillation /ENSO/
neutral conditions are favored into summer 2013.
HYDROLOGIC SUMMARY AND OUTLOOK...
The USGS Water Watch indicates more gages going online for the
season. Streamflows for most sites west of the continental divide
are in the normal to above normal percentiles. East of the divide,
along the northern Rocky Mountain Front streamflows are mostly in
the normal to above normal percentiles. Across southwest, south
central and southeast, streamflows are mostly in the below to much
below normal percentiles. Most stations in northeast Montana have
not gone online for the season with many still being ice affected.
The SWSI /Surface Water Supply Index/ issued by the Natural Resources
Conservation Service indicates streams west of the Continental
Divide range from `Moderately Dry` /Mission Valley, Little
Bitterroot and Blackfoot basins/ to `Slightly Wet` /Kootenai below
Libby Dam and the Yaak basins/. A similar range is seen on the east
side of the Continental Divide with `Moderately Dry` /Stillwater,
Little Bighorn and Birch-Dupuyer Creeks basins/ to `Slightly
Wet` /Smith, Milk basins/ conditions.
Reservoirs across Montana are mostly near to slightly above
historical averages for the date. Notable exceptions are Gibson
Reservoir /44 percent of historical average/, Cataract Reservoir /65
percent of historical average/, Martinsdale Reservoir /72 percent of
historical average/, Cottonwood Reservoir /82 percent of historical
average/, Middle Creek Reservoir /83 percent of historical average/,
and Nilan Reservoir /88 percent of historical average/.
Drier than average conditions across much of Montana, particularly
east of the divide, in February and early March have caused the
snowpack in several basins to drop slightly below their median for
the date. Those basins still below historical medians are Bitterroot
River Basin /89 percent of median/, and the Lower Yellowstone River
Basin /89 percent of median/.
NEXT ISSUANCE DATE...
Through the spring, updates to this product will be made on a monthly
basis, typically between the 15th and 25th. The next issuance of the
drought information statement for Montana should be no later than
Friday April 19 2013.
RELATED WEB SITES...
Additional information on current drought conditions may be found at
the following web addresses...
U.S. Drought Monitor...www.droughtmonitor.unl.edu/
NOAA Drought Information Center...www.drought.noaa.gov/
National Integrated Drought Information System /NIDIS/Drought
Montana drought and water information...drought.mt.gov
NWS Great Falls drought information...
Western Regional Climate Center...wrcc.dri.edu
Climate Prediction Center /CPC/...www.cpc.ncep.noaa.gov/
NWS River Information...water.weather.gov/ahps/
USGS Water Resources of Montana...mt.water.usgs.gov/
US Bureau of Reclamation Great Plains Region...www.usbr.gov/gp/
US Bureau of Reclamation Pacific Northwest Region...www.usbr.gov/pn/
US Army Corps of Engineers Omaha District...
Natural Resources Conservation Service Water Supply...
National Interagency Fire Center Predictive Services...
The Drought Monitor is a multi-agency effort involving NOAA`s
National Weather Service and National Climatic Data Center, the U.S.
Department of Agriculture, state and regional centers climatologists
and the National Drought Mitigation Center. Information for this
statement has been gathered from NWS and FAA observation sites,
Montana Department of Natural Resources, State Cooperative Extension
Services, USDA, NRCS, USACE and USGS.
QUESTIONS OR COMMENTS...
If you have any questions or comments about this Drought Information
Statement, please contact...
National Weather Service
5324 Tri-Hill Frontage Road
Great Falls MT 59404