Drought Information Statement
Issued by NWS
AXUS75 KTFX 021937
DROUGHT INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
137 PM MDT THU JUL 2 2015
...Montana Drought Information Statement as of July 2 2015...
The Montana Drought Information Statement is issued by the National
Weather Service Office in Great Falls in cooperation and coordination
with the National Weather Service Offices in Missoula, Billings, and
Drought Conditions Worsening Over Western Montana
Drought conditions area increasing over much of the western third of
Montana and the hi-line.
Preliminary analyses for June show the western half of Montana
received well below average precipitation. Most areas received less
than 50% of average, with some areas receiving less than 25% of
average. June is climatologically the wettest month for Montana as a
whole. South-central into northeast Montana, conditions were mixed
with some areas receiving above to well above average precipitation,
while other areas saw below to well below average amounts. Southeast
and far eastern Montana were the areas of the state that ended with
widespread areas of above to well above average precipitation.
Temperatures trends follow a similar geographic pattern - daytime
highs averaged 6 to 12 degrees above average across the western third
to half of Montana. The eastern half of the state saw daytime highs
near average. Overnight lows were closer to average in most areas,
however, portions of central, south-central, and southeast have large
areas 4 to 6 degrees above average, and pockets 6 to 8 degrees above
Detailed summary of June weather conditions for Montana
As of June 30, the portion of Montana in some stage of drought on the
National Drought Monitor had increased to just over 40 percent /40.56
percent/. More than half of this /24.33 percent/ falls in the D1 -
Moderate Drought category, with over 16 percent /16.23 percent/ in
the D2 - Severe Drought category. None of Montana was classified as
D3 - Extreme Drought, or D4 - Exceptional Drought. Nearly 20 percent
of Montana /19.36 percent/ is classified as D0 - Abnormally Dry.
National Drought Monitor
Montana Portion of National Drought Monitor
The Drought Outlook released June 18 shows drought persistence or
intensification through September over those portions of west and
southwest Montana currently in a D1 - Moderate Drought status. This
assessment is based on current conditions, long term forecasts and
the climatic trends for drier weather in Montana during the summer
and early autumn.
Seasonal Drought Outlook
Precipitation for all periods has been below normal west of the
Continental Divide, and east of the Divide from north-central to
southwest Montana. Areas east, south-east, and portions of central
and south-central have been seeing near to above normal
June 2015 percent of normal precipitation
Crop Year 2015 percent of normal precipitation
Calendar Year 2015 percent of normal precipitation
Water Year 2015 percent of normal precipitation
Preliminary map of percent of normal precipitation for the current
month provided by the Western Region Climate Center
HYDROLOGIC SUMMARY AND OUTLOOK...
Streamflows in the western half of Montana are mostly in the below to
much below normal range...the 24th percentile or lower. A few
stations are hitting new daily record low flows...mainly west of the
Continental Divide. Over the eastern half of Montana, streamflows are
mostly in the near-normal percentiles with some sites in the far
southeast corner of the state running much above normal for the date.
Overall, streamflows during the summer are expected to be below to
well below average statewide.
Streamflow forecasts for rivers and sites west of the Continental
Divide provided by the Northwest River Forecast Center - NWRFC - in
Streamflow forecasts for rivers and sites east of the Continental
Divide provided by the Missouri Basin River Forecast Center - MBRFC -
in Pleasant Hill, Missouri.
SURFACE WATER SUPPLY INDEX...
The Surface Water Supply Index - SWSI - is a measure of available
surface water availability for the upcoming months. The SWSI accounts
for mountain snowpack, mountain precipitation, streamflow, reservoir
storage and soil moisture. SWSI values are provided by the Natural
Resources Conservation Service - NRCS - with the US Dept of
The June SWSI indicates most streams across the western Montana are
rated mostly Moderately to Extremely Dry. Streams in central and
eastern portions of the state are faring better with most in the Near
As of May 1, reservoirs across Montana are mostly near to slightly
above historical averages for the date, and irrigation demands are
currently being met
SUMMARY OF IMPACTS...
STATE AND LOCAL ACTIONS...
The Montana Governor`s Drought and Water Supply Advisory Committee
met June 18. Copies of the presentations provided at the meeting can
be reviewed through the Committee`s website below. Reports all
discussed the drier conditions and resulting impacts...particularly
west. The Committee will continue to meet monthly through the summer
and early autumn months. The next meeting will be held July 16.
SOIL MOISTURE CONDITIONS...
Recent hot weather and plant growth/evapotranspiration are tasking
soil moisture content. Recent thunderstorms brought precipitation to
some areas, however, this was very localized. Across northwest, north
central, central and eastern Montana losses were noted during the
last month. In spite of these changes, soil moisture across north
central and eastern Montana continues to run above normal while west,
southwest and south central Montana continue to run below normal.
Soil Moisture Change
Surface Soil Moisture
Root Zone Soil Moisture
As of June 28, both topsoil and subsoil were drier than last year and
the 5 year average.
Topsoil Short to Very Short - 48%
Topsoil Adequate to Surplus - 52%
Subsoil Short to Very Short - 40%
Subsoil Adequate to Surplus - 60%
Topsoil Short to Very Short - 21%
Topsoil Adequate to Surplus - 79%
Subsoil Short to Very Short - 24%
Subsoil Adequate to Surplus - 76%
Topsoil Short to Very Short - 17%
Topsoil Adequate to Surplus - 83%
Subsoil Short to Very Short - 19%
Subsoil Adequate to Surplus - 81%
As of July 3 and continuing until further notice, Stage 1 Fire
Restrictions are in place for Lincoln, Flathead, Sanders, Lake,
Mineral, Missoula, Powell, and Ravalli Counties. There were no Stage
2 Fire Restrictions in place.
For the 2015 wildfire season, Montana has had 660 wildfires with a
combined total of over 39 thousand acres /39,285/ with an estimated
cost to fight of over 2 million dollars /2,124,060/. Nineteen of these
fires have surpassed 100 acres in size. The largest of these includes
Sheep Draw /13,949 acres/, Slough /4,500 acres/, Bringoff /4,094
acres/, and Hercules /3,364 acres/.
CURRENT WATER RESTRICTIONS...
None known at this time
OTHER IMPACTS - RECREATIONAL...
None known at this time
June for Montana ranged from colder than average mid-month to warmer
than average by the end of the month. Overall, Montana was mostly
warmer and drier than average. While eastern areas of the state
received above to areas of well above average precipitation, western
portions of Montana were dry with large areas of well below average
precipitation. For Great Falls it was the driest June on record /123
years of record/, Belgrade saw its third driest /78 years of record/,
Bozeman-MSU and Havre their fourth driest of record /both with 135
years of record/. Temperatures for June 2015 averaged 5.4 degrees
Fahrenheit above normal, the warmest June for Montana since 1988.
High temperature for the state was 109 degrees Fahrenheit at Troy on
June 28. Low temperature was 27 degrees Fahrenheit at Wisdom June 14.
Greatest precipitation for the month was 5.70 inches at Belltower in
Carter County. Wind averaged 7.6 miles per hour, the 3rd calmest of
record for June since 1936.
Historic ranking of statewide temperatures
Historic ranking of statewide precipitation
The July outlook for Montana released June 18 indicates a 33 to 40
percent chance temperatures will average above normal over the
western third of Montana with equal chances temperatures will average
above, below or near normal for central and eastern Montana.
The precipitation outlook for July updated June 18 shows a 33 to 40
percent chance precipitation will average above normal over the
central and southern thirds of Montana with equal chances
precipitation will average above, below or near normal for northern
July Outlook for Temperatures
July Outlook for Precipitation
For the August through October period, the outlook shows a 50 to 60
percent chance temperatures will average above normal west of the
Continental Divide, a 40 to 50 percent chance temperatures will
average above normal over north-central, central and southwest
Montana, and a 33 to 40 percent chance temperatures will average
above normal over eastern Montana.
The precipitation outlook for August through October shows a 33 to 40
percent chance for above normal precipitation across the extreme
southern border of Montana. The remainder of the state has equal
chances for above, below, or near normal precipitation over the
August - October Outlook for Temperatures
August - October Outlook for Precipitation
In an update released June 11, the National Weather Service Climate
Prediction Center with the International Research Institute for
Climate and Society stated that there is a greater than 90% chance
that El Nino will continue through Northern Hemisphere fall 2015, and
around an 85% chance it will last through the 2015-16 winter.
El Nino/La Nina Discussion
NEXT ISSUANCE DATE...
Updates to this product will be made on an as needed basis, with at
least one issuance per month when drought conditions exist. This
update typically will be between the 15th and 25th. The next issuance
of the Drought Information Statement for Montana should be no later
than Thursday, July 16, 2015.
RELATED WEB SITES...
Additional information on current drought conditions may be found at
the following web addresses...
html - National Drought Outlook
http://www.droughtmonitor.unl.edu/ - U.S. Drought Monitor
http://www.drought.noaa.gov/ - NOAA Drought Information Center
http://drought.gov - National Integrated Drought Information System
- NIDIS - Drought Portal
http://drought.mt.gov - Montana Drought and Water Information
http://www.wrh.noaa.gov/tfx/main/drought.php?wfo=tfx - NWS Great
Falls Drought Information
http://wrcc.dri.edu - Western Regional Climate Center
http://www.cpc.ncep.noaa.gov/ - Climate Prediction Center /CPC/
http://water.weather.gov/ahps/ - NWS River Information
http://mt.water.usgs.gov/ - USGS Water Resources of Montana
http://www.usbr.gov/gp/ - US Bureau of Reclamation Great Plains
http://www.usbr.gov/pn/ - US Bureau of Reclamation Pacific
http://www.nwo.usace.army.mil/- US Army Corps of Engineers Omaha
http://www.mt.nrcs.usda.gov/snow/ - Natural Resources Conservation
Service Water Supply
http://www.predictiveservices.nifc.gov/predictive.htm - 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 US
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.
This data is provided by the many agencies listed above. This does
not constitute an endorsement by the NWS of any information, products
or services by the content provider. The NWS does not own or operate
these sites and is not responsible for site maintenance or data
accuracy. Use this data at your own risk.
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