Drought Information Statement
Issued by NWS Great Falls, MT
AXUS75 KTFX 192233
DROUGHT INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
433 PM MDT FRI APR 19 2013
...Drought Conditions Gradually Improving Across Montana...
A ridge of high pressure aloft along the west coast continued to be a
dominating factor for the weather across Montana during March. This
time of year, the high pressure ridge is typically centered slightly
further east. The westward shift this year kept a cool northwest
flow over much of the state resulting in drier than normal
conditions. March was the first month since October to record below
normal temperatures for the state as a whole, and is only the third
month of the last twelve to record below normal temperatures.
The monthly accumulated precipitation across Montana was below
normal. However, northeast Montana did see several storm events with
a large portion of that corner of the state receiving 200 to 300
percent of normal precipitation. An area in northwest Montana
received 150 to 200 percent of normal precipitation, with Troy,
Montana recording the highest amount in the state for the month at
3.74 inches of liquid precipitation. For the past 12 months, the
state is now 2.10 inches below normal for precipitation. Snowfall
was on the light side for March, with the exception of northeast
Montana. For the state as a whole, the average of 5.7 inches of snow
was 4.3 inches below average. Cooler temperatures did delay the
onset of snowmelt that begins this time of year.
For the state as a whole, winds were below average in March.
As of April 16, the portion of Montana in some stage of drought on
the National Drought Monitor was just under 32 percent /31.96/, up
slightly from March 19. The portion of Montana in the D3 Extreme
Drought category has dropped and is now a little over 2
percent /2.28/. Less than 10 percent /9.96/ is in the D2 Severe
Drought category. That portion of the state in the D1 Moderate
Drought category is nearly 20 percent /19.72/, and just over 14
percent /14.16/ of Montana is in the D0 Abnormally Dry category.
The Drought Outlook released April 18 shows no drought development
expected through the end of July 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 some
improvement during the April through July period. Across southwest
and south central Montana, the Drought Outlook indicates the drought
will be ongoing. This assessment is based on current near to
slightly below normal snowpack in the mountains, good reservoir
storage and a climate outlook that is indicating better chances for
drier than normal precipitation amounts for the May through July
period. This area will be monitored closely as we move through our
SUMMARY OF IMPACTS...
STATE AND LOCAL ACTIONS...
The Montana Governor`s Drought and Water Supply Advisory Committee
had its mandatory April meeting Thursday, April 18, and will
continue to meet monthly through the spring, summer and early
SOIL MOISTURE CONDITIONS...
At mid-April, soil moisture over Montana west of the Continental
Divide was noted to be above normal while areas in central, south
central and southeast Montana were noted to be below normal. Soils
in most areas of Montana are now frost free for the season.
Supplemental feeding continues and is not uncommon as Montana moves
through early spring. As of mid-April, 93 percent of cattle /78
percent last year/ and 95 percent of sheep /76 percent of last year/
were receiving supplemental feed. Early spring grazing conditions
are 48 percent open, well below the 81 percent at this same time
last year, a result of recent snow storms. Livestock grazing areas
rated as `difficult` were 30 percent /7 percent last year/ and 22
percent `closed` due to drought and/or snow /12 percent last year/.
As of April 15, topsoil moisture ranked as short to very short was 33
percent /41 percent last year/. Subsoil moisture short to very short
was 50 percent /39 percent last year/. Winter wheat condition was
near that of last year with 52 percent good to excellent /53 percent
last year/. Due to snowfall and cold nights, 19 percent of winter
wheat is still dormant /5 percent last year/.
March across Montana was generally cooler and drier than normal.
Temperatures for March 2013 were the 59th coldest of 119 years of
record while precipitation for the state was the 33rd driest. During
the first three weeks of April, the eastern half of Montana has
received near to much above normal precipitation. The remainder of
the state has reported below to well below normal precipitation for
the month to date.
The May outlook for Montana released April 18 indicates a 33 to 40
percent chance temperatures will be above normal across southwest
and south central Montana. For the remainder of the state, there are
equal chances temperatures will be above, below or near normal.
Additionally for May, there is a 33 to 40 percent chance
precipitation will be below normal west of the Continental Divide.
East of the Continental Divide, there are equal chances
precipitation will be above, below or near normal for the month.
For our summer months of June through August, the outlook indicates
better chances for above normal temperatures across the southern
third of the state, with equal chances for above, below or near
normal temperatures for the central and northern thirds. The
precipitation outlook for June through August shows a 40 to 50
percent chance for below normal precipitation with the Continental
Divide areas and adjacent plains showing a 33 to 40 percent chance
for below normal precipitation. The central and eastern plains of
the state have equal chances for above, below or near normal
precipitation through the summer months.
In an update released April 4, 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. Along the Continental
Divide and across the southern half of the state, streamflows at
several gages are in the below to well below normal percentiles.
This can be attributed to not only below normal precipitation but
also to cooler than average conditions slowing the seasonal
snowmelt. Most stations in northeast Montana are in the above to
well above normal percentiles due to a series of precipitation
events in that portion of the state.
The SWSI /Surface Water Supply Index/ issued by the Natural Resources
Conservation Service indicates streams west of the Continental
Divide range from `Extremely Dry` /Mission Valley basin/
to `Extremely Wet` /South Fork Flathead basin/. The range east of
the Continental Divide is less dramatic ranging from `Moderately
Dry` /Marias above Tiber, Birch-Dupuyer Creeks, Stillwater, Rock/Red
Lodge Creeks and Little Bighorn basins/ to `Slightly Wet` /St. Mary
Reservoirs across Montana are mostly near to slightly above
historical averages for the date. Notable exceptions are Gibson
Reservoir /49 percent of historical average/, Cottonwood
Reservoir /63 percent of historical average/, Mission Valley /66
percent of historical average/, Martinsdale Reservoir /78 percent of
historical average/, Cataract Reservoir /79 percent of historical
average/, Nevada Creek Reservoir /82 percent of historical average/,
Flathead Lake /85 percent of historical average/, Middle Creek
Reservoir /86 percent of historical average/, and Willow Creek
Reservoir /88 percent of historical average/.
Continued drier than average conditions across much of west and
southwest Montana in February and March resulted in the snowpack in
several basins continuing to drop below their median for the date.
The percent of median for the date as of mid-April ranged from 89
percent of median for the date for the Lower Clark Fork to 123
percent median for the date for the St. Mary and Milk River Basins.
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 May 17, 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 Portal
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