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DROUGHT CONDITIONS HAVE EXPANDED INTO THE WESTERN
SANDHILLS AND SOUTHWESTERN NEBRASKA.
SYNOPSIS
THE WEATHER PATTERN THROUGH LATE FEBRUARY AND EARLY MARCH WAS
CHARACTERIZED BY FAIRLY QUICK MOVING LOW PRESSURE SYSTEMS...MUCH
LIKE WHAT HAS BEEN THE CASE SINCE THE BEGINNING OF THE YEAR. THIS
PATTERN ALSO CONTINUED THE TREND OF LARGE VARIATIONS IN TEMPERATURES
AS ANY COLD AIR INTRUSIONS...AS WELL AS LARGE WARM-UPS...WERE SHORT
LIVED.
THOUGH SOME BRIEF PERIODS OF PRECIPITATION OCCURRED...MOST OF THE
PRECIPITATION WAS LIGHT AND OCCURRED ACROSS NORTHERN NEBRASKA. THE
EXCEPTION TO THIS...AND A CHANGE IN THE WEATHER PATTERN OCCURRED
MARCH 16TH AND 17TH...WHEN A POTENT WINTER WEATHER SYSTEM WAS ABLE
TO ACQUIRE SIGNIFICANT MOISTURE TO CREATE AREAS OF HEAVY SNOWFALL
ACROSS PORTIONS OF SOUTHWEST INTO CENTRAL NEBRASKA. IN SOME CASES
THIS WAS THE MOST SIGNIFICANT MOISTURE RECEIVED SINCE MID DECEMBER.
LOCAL AREAS AFFECTED
AS OF MARCH 20...ACCORDING TO THE US DROUGHT MONITOR...SEVERE
DROUGHT CONDITIONS EXISTED WEST OF A LINE FROM RUSHVILLE TO ANTIOCH.
EAST OF THIS LINE...TO A LINE EXTENDING FROM MERRIMAN...TO
LEWELLEN...TO HAYES CENTER MODERATE DROUGHT CONDITIONS EXISTED.
MODERATE DROUGHT CONDITIONS HAVE EXPANDED OVER THE LAST MONTH...AND
NOW ENCOMPASS ALL OF GARDEN...CHASE...PERKINS AND WESTERN PORTIONS
OF KEITH AND HAYES COUNTIES.
CLIMATE SUMMARY
VERY LITTLE PRECIPITATION FELL ACROSS SOUTHWEST AND CENTRAL NEBRASKA
FOR THE MONTH OF FEBRUARY WITH NORTH PLATTE...BROKEN BOW...AND
IMPERIAL ALL RECORDING SIGNIFICANTLY BELOW NORMAL PRECIPITATION.
THIS IS THE SECOND MONTH IN A ROW FOR SOUTHWEST AND CENTRAL NEBRASKA
TO RECEIVE VERY LITTLE PRECIPITATION. VALENTINE ON THE OTHER HAND
CONTINUED TO BE IN THE STORM TRACK FOR SOME MODERATE PRECIPITATION
EVENTS...RECORDING NORMAL PRECIPITATION FOR THE MONTH. OVER THE LAST
6 MONTHS...SEPTEMBER TO FEBRUARY...ONLY VALENTINE HAS RECORDED ABOVE
NORMAL PRECIPITATION. NORTH PLATTE...BROKEN BOW...AND IMPERIAL HAVE
HAD A 6 MONTH DEFICIT...WITH IMPERIAL RECORDING LESS THAN HALF OF
THEIR NORMAL 6 MONTH TOTAL.
6 MONTH PRECIP/INCHES LAST MONTH PRECIP/INCHES
LOCATION SEP-FEB NORMAL DEP | FEB NORMAL DEP
NORTH PLATTE 4.10 4.62 -0.52 | 0.10 0.51 -0.41
VALENTINE 5.34 4.66 +0.68 | 0.48 0.48 0.00
BROKEN BOW 4.13 5.70 -1.57 | 0.02 0.48 -0.46
IMPERIAL 2.21 4.83 -2.62 | 0.02 0.53 -0.51
THE OVERALL WEATHER PATTERN CONTINUED TO BE SIMILAR TO THAT OF
JANUARY WITH TEMPERATURES FLUCTUATING UP AND DOWN AS A PROGRESSIVE
PATTERN RESULTED IN NUMEROUS FAST MOVING COLD FRONTS. THE LACK OF
SNOW ACROSS SOUTHWEST AND CENTRAL NEBRASKA ALLOWED DAILY
TEMPERATURES TO REBOUND TO ABOVE NORMAL IN BETWEEN COLD OUTBREAKS.
THE RESULTING AVERAGE MONTHLY TEMPERATURES FOR NORTH PLATTE...BROKEN
BOW...AND IMPERIAL WAS NEAR OR ABOVE NORMAL. HOWEVER NORTHERN
NEBRASKA HAD MORE SNOWFALL...WHICH RESULTED IN BELOW NORMAL
TEMPERATURES FOR VALENTINE.
AVERAGE TEMPERATURE/DEGREE F
LOCATION DEC NORMAL DEP | JAN NORMAL DEP | FEB NORMAL DEP
NORTH PLATTE 21.0 25.7 -4.7 | 23.2 23.2 0.0 | 29.5 29.4 0.1
VALENTINE 22.2 23.6 -1.4 | 20.2 20.8 -0.6 | 25.4 26.6 -1.2
BROKEN BOW 23.6 23.8 -0.2 | 23.2 20.9 2.3 | 27.5 26.3 1.2
IMPERIAL 22.9 27.0 -4.1 | 25.5 25.0 0.5 | 32.1 30.4 1.7
RIVER AND STREAMFLOW CONDITIONS
STREAMFLOW CONDITIONS REMAINED LOW ACROSS SOUTHWEST NEBRASKA BUT
REMAINED STEADY AND NEAR NORMAL ACROSS THE REMAINDER OF THE RIVER
BASINS.
RESERVOIR AND LAKE LEVELS
LAKE LEVELS AT THE END OF FEBRUARY REMAINED MUCH BELOW NORMAL FOR
ENDERS DAM AND LAKE MCCONAUGHY. LAKE MCCONAUGHY GAINED SIXTY SIX
THOUSAND ACRE FEET FROM THE PREVIOUS MONTH TO A RESERVOIR STORAGE OF
687800 ACRE FEET. THIS WAS AN INCREASE OF 3.9 PERCENT TO 39.5
PERCENT OF CAPACITY TO END THE MONTH. THIS DOES HOWEVER COMPARE TO A
LAKE ELEVATION 5.5 FEET ABOVE LAST YEARS LAKE ELEVATION. ENDERS DAM
RECORDED A RESERVOIR STORAGE OF 16900 ACRE FEET WHICH REMAINED
STEADY FROM THE PREVIOUS MONTH WITH 39 PERCENT OF CAPACITY. RED
WILLOW DAM RECORDED A RESERVOIR STORAGE OF 25640 ACRE FEET.
RESERVOIR CAPACITY ROSE SLIGHTLY TO 71 PERCENT. RED WILLOW DAM
RECORDED THE HIGHEST RESERVOIR STORAGE TO END THE MONTH SINCE 2000.
OTHER RESERVOIRS WHICH ARE SPRING FED SAW THE USUAL RESERVOIR
RECHARGE. MEDICINE CREEK DAM RECORDED A RESERVOIR STORAGE OF 33900
ACRE FEET. RESERVOIR CAPACITY WAS NEARLY STEADY AT 95.0 PERCENT.
CALAMUS RESERVOIR RECORDED A RESERVOIR STORAGE OF 112700 ACRE FEET.
RESERVOIR CAPACITY ROSE SLIGHTLY TO 88.5 PERCENT. MERRITT RESERVOIR
RECORDED A RESERVOIR STORAGE OF 61200 ACRE FEET. RESERVOIR CAPACITY
WAS STEADY AT 91.5 PERCENT.
ALTHOUGH MOUNTAIN SNOWPACK WAS 105 TO 115 PERCENT OF NORMAL TO END
THE MONTH OF FEBRUARY...DUE TO THE ALLOTMENT OF UPSTREAM
RESERVOIRS...DELIVERY OF WATER TO THE NORTH PLATTE RIVER UPSTREAM OF
LAKE MCCONAUGHY IS EXPECTED TO ONLY BE 80 PERCENT OF AVERAGE.
THEREFORE LIMITED RELEASES FOR CONSERVATION PURPOSES IS PLANNED...AS
LAKE MCCONAUGHY REMAINS AT CRITICALLY LOW LAKE LEVELS GOING INTO THE
IRRIGATION SEASON.
FIRE DANGER IMPACTS
AN INCREASE IN FIRE ACTIVITY HAS BEEN SEEN IN
THE FIRST HALF OF MARCH...BOTH DUE TO WILDFIRE ACTIVITY AND
PRESCRIBED BURNING. PRIOR TO THE MORE SIGNIFICANT SNOWFALL ACROSS
SOUTHWEST AND CENTRAL NEBRASKA DURING THE MIDDLE OF THIS MONTH...DRY
CONDITIONS REMAINED IN PLACE. THIS MOISTURE WILL HELP EASE FIRE
CONDITIONS ONLY TEMPORARILY. THE NEXT SHORT WARM AND DRY PERIOD WILL
BE ENOUGH TO DRY THE FINE DEAD FUELS IN PLACE ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...RETURNING THEM TO A READY TO BURN STATE.
WESTERN NEBRASKA WILL BE APPROACHING A CLIMATOLOGICALLY FAVORED
PERIOD FOR LARGE FIRE GROWTH. THIS IS DUE TO THE DEAD FINE FUELS IN
PLACE AND WEATHER CONDITIONS FAVORABLE FOR RAPID FIRE SPREAD SUCH AS
WARM PERIODS AHEAD OF COLD FRONTS AND THE ASSOCIATED STRONG WINDS
BEHIND THE FRONT.
FIRE DANGER CAN BE DETERMINED THROUGH EITHER THE 10-HOUR AND
100-HOUR DEAD FUEL MOISTURES...OR THE KEETCH-BYRAM DROUGHT INDEX
(KBDI). THE KBDI INDEX IS BROKEN INTO FOUR CATEGORIES WHICH ARE USED
TO DETERMINE THE SUSCEPTIBILITY OF GROUND FUELS TO FIRE DANGER. THE
FOUR CATEGORIES AND A BRIEF DESCRIPTIONS ARE AS FOLLOWS:
LOW...WET WITH LITTLE DANGER OF FIRE INITIATION
MODERATE...DRYING OCCURRING WITH SOME FIRE DANGER
HIGH...GROUND COVER DRY AND WILL BURN READILY
EXTREME...DEAD AND LIVE FUELS WILL BURN READILY
THE MAJORITY OF WESTERN AND NORTH CENTRAL NEBRASKA REMAIN ON THE
LOW END OF THE KBDI INDEX...HOWEVER PORTIONS OF THE PANHANDLE INTO
THE WESTERN SANDHILLS ARE IN THE MODERATE CATEGORY. THESE VALUES ARE
EXPECTED TO INCREASE OVER THE NEXT 30 DAYS. A DAILY GRAPHIC OF THE
KBDI INDEX AND DEAD FUEL MOISTURE CAN BE FOUND ON THE WILDLAND FIRE
ASSESSMENT SYSTEM (WFAS) WEB SITE AT:
HTTP://WWW.WFAS.US
OR THE NORTH PLATTE NWS WEB SITE AT:
HTTP://WWW.CRH.NOAA.GOV/LBF/FORECASTS/FIREWX/FIREWX.PHP
THE NORTH PLATTE NWS WEB SITE ALSO HAS ADDITIONAL DATA AND FORECASTS
RELATED TO FIRE WEATHER CONDITIONS ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA.
PRECIPITATION AND TEMPERATURE OUTLOOKS
THE LATEST 6 TO 10 DAY AND 8 TO 14 DAY OUTLOOKS...WHICH COVER
TEMPERATURES AND PRECIPITATION FROM MARCH 26 TO APRIL 3...IS FOR
ABOVE NORMAL TEMPERATURES AND BELOW NORMAL PRECIPITATION. THE LATEST
30 DAY OUTLOOK FOR APRIL IS FOR NEAR NORMAL TEMPERATURES AND NEAR
NORMAL PRECIPITATION FOR ALL OF WESTERN AND NORTH CENTRAL NEBRASKA.
NORMAL PRECIPITATION FOR APRIL IS 1.97 INCHES AT BOTH VALENTINE AND
NORTH PLATTE. THE LATEST 90 DAY OUTLOOK WHICH COVERS APRIL...MAY AND
JUNE...IS FOR ABOVE NORMAL TEMPERATURES IN SOUTHWESTERN AREAS AND
NEAR NORMAL TEMPERATURES ELSEWHERE. THE PRECIPITATION OUTLOOK FOR
THE SAME TIME PERIOD IS FOR BELOW NORMAL PRECIPITATION IN
SOUTHWESTERN AREAS...AND NEAR NORMAL PRECIPITATION ELSEWHERE.
QUESTIONS OR COMMENTS...IF YOU HAVE ANY QUESTIONS OR COMMENTS ABOUT
THIS INFORMATION PLEASE CONTACT:
CHRIS BUTTLER
CLIMATE SERVICES FOCAL POINT
NATIONAL WEATHER SERVICE
NORTH PLATTE NE
CHRISTOPHER.BUTTLER@NOAA.GOV
RELATED WEB SITES
LOCAL WEATHER...CLIMATE AND WATER INFORMATION
HTTP:://WWW.CRH.NOAA.GOV/LBF
ADDITIONAL RIVER AND RESERVOIR INFORMATION
USGS - HTTP://WATER.USGS.GOV
CNPPD - HTTP://CNPPD.COM/LAKE_LEVELS.HTM
US DROUGHT MONITOR
HTTP://WWW.DROUGHT.UNL.EDU/DM/INDEX.HTML
CLIMATE PREDICTION CENTER
HTTP://WWW.CPC.NCEP.NOAA.GOV
ACKNOWLEDGMENTS
THE DROUGHT MONITOR IS A MULTI-AGENCY EFFORT
INVOLVING THE NATIONAL WEATHER SERVICE AND NATIONAL CLIMATIC DATA
CENTER...THE USDA...STATE AND REGIONAL CENTER CLIMATOLOGISTS AND THE
DROUGHT MITIGATION CENTER. INFORMATION FOR THIS STATEMENT HAS BEEN
GATHERED FROM NWS AND FAA OBSERVATION SITES...STATE COOPERATIVE
EXTENSION SERVICES...USGS...AND THE CENTRAL NEBRASKA PUBLIC POWER
AND IRRIGATION DISTRICT.
NEXT ISSUANCE
THIS PRODUCT WILL BE ISSUED ON THE THIRD THURSDAY
OF THE MONTH. THE NEXT ISSUANCE WILL BE APRIL 17 2008.
JWS/MM/DP/KAR/CLB
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