Flood Potential Outlook
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
Versions:
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FGUS75 KGJT 271959
ESFGJT
COC007-029-033-037-045-051-053-067-077-081-083-085-091-097-103-
107-111-113-UTC009-019-037-047-062000-
Water Supply Outlook
National Weather Service Grand Junction CO
1259 PM MST Thu Feb 27 2025
...SPRING FLOOD AND WATER RESOURCES OUTLOOK FOR WESTERN COLORADO
AND EASTERN UTAH ISSUANCE NUMBER 2...
...Hydrologic Service Area (HSA)...
The Grand Junction HSA falls almost entirely within the Upper
Colorado River Basin, and provides a population of over 40 million
people with water across the southwestern US. The area
encompasses seven basins including; the Upper Green River Basin
and the Duchesne River Basin in eastern Utah, and the Yampa and
White River Basins, Upper Colorado River Mainstem, Gunnison River
Basin, Dolores and San Miguel River Basins, and the Upper San Juan
River Basin in western Colorado. Each river and their tributaries
feed the Colorado River above Lake Powell, and are primarily fed
by snowpack accumulation (typically) from November - April. As the
snow melts in the spring, the Upper Colorado River Basin begins
to fill lakes, rivers, streams, reservoirs and trans-basin
diversions from Denver to Los Angeles. Thus, seasonal water supply
and resource outlooks across the Grand Junction HSA are crucial
to water management during the late winter and early spring, in
order to support various sectors including hydropower,
agriculture, recreation, and municipal uses that in turn support
the needs of a vast population.
...Water Supply Outlooks Summary/Key Messages...
The potential for spring flooding due to snowmelt is low at this
time, and season water supply volumes remain near to below normal
for the Upper Colorado River Basin.
Water supply guidance as a percentage of average (as of February
18th) for the April through July runoff period are listed below:
Yampa/White 97% Upper CO Mainstem 104%
Gunnison 86% Dolores 63%
San Juan 55% Upper Green 72%
Duchesne 76%
Forecast volumes continue to run blow normal due to current
snowpack, soil conditions and weather outlooks.
NOTE: In normal years, additional snowpack can accumulate in the
mountains through the first half of April. However, it`s worth
noting that precipitation, strong winds and blowing dust, a cold
spring or unseasonably warm spring during the snowmelt season can
greatly affect total runoff volume and timing of peak flow.
...Summary of Water Year Conditions...
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Observed Precipitation
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An active pattern returned a round of precipitation at the beginning
of February, as well as another Atmospheric River (AR) contributing to
widespread precipitation by mid-month. Early February`s system favored
northern subbasins, however, all basins received some much needed
moisture by the middle of the month. Even though the recent AR activity
certainly helped the deteriorating conditions across southwest CO and
southeast UT, seasonal precipitation amounts remain near to below normal
across the Upper Colorado Basin.
Western Colorado and eastern Utah Water Year Precipitation as of
February 27th:
Yampa/White 99% Upper CO Mainstem 96%
Gunnison 90% Dolores/San Miguel 82%
San Juan 72% Duchesne 91%
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Observed Snowpack
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Above normal precipitation through the month of February has
helped northern and high elevation subbasins (i.e. headwaters of
the Gunnison, Colorado and Yampa/White rivers) maintain near to
above normal snowpack conditions. However, despite some decent
precipitation events across the entire region, the month has also
sustained warmer than normal temperatures which have negatively
impacted the snowpack, specifically in lower elevations and
southern subbains. As a result, snowpack conditions across south
and western CO and southeastern UT remain below normal.
Western Colorado and eastern Utah Average SWE by February 27th:
Yampa/White 98% Upper CO Mainstem 98%
Gunnison 86% San Miguel/Dolores 76%
San Juan 62% Duchesne 82%
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Soil Moisture
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A relatively active monsoon in 2024 did support an improvement in
soil conditions, in comparison to Fall 2023. More notably, soil
conditions across the upper San Juan, Dolores, San Miguel and
Gunnison basins showed up to a 50 percent average increase from
2023. Elsewhere, near normal to slightly below normal soil moisture
condition`s were observed for the Colorado Headwaters and the
Yampa/White Basins.
Antecedent soil moisture can impact the efficiency of early
spring runoff. Thus, water supply forecasts for basins with above
average soil moisture tend to experience more efficient runoff
from rainfall and snowmelt, while basins with below average
antecedent conditions show less efficient runoff until soil
saturation is reached.
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STATUS of RESERVOIR STORAGE FOR WFO Grand Junction Reservoirs
PERIOD ENDING: February 26, 2025
Figures are in 1000 Acre Feet
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C U R R E N T Y R L A S T Y R 1991-2020
EOM % of % of EOM % of JAN 31 Usable
Storage Average Capacity Storage Average Avg Storage Capacity
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GUNNISON - BLUE MESA | 509.6| 101| 62|| 568.2| 110|| 515.2| 830.0|
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GUNNISON - CRYSTAL RE| 8.3| 113| 48|| 9.0| 123|| 7.3| 17.5|
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CRAWFORD RESERVOIR | 5.6| 90| 40|| 6.3| 109|| 5.8| 14.0|
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FRUITGROWERS DAM - A | 2.0| 55| 44|| 1.6| 53|| 3.1| 4.5|
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FLORIDA - LEMON RESER| 22.8| 126| 57|| 15.7| 87|| 18.1| 39.8|
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DOLORES - MCPHEE RESE| 209.3| 81| 55|| 291.9| 114|| 256.3| 381.1|
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GUNNISON - MORROW POI| 111.1| 101| 92|| 111.2| 101|| 109.9| 117.0|
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MUDDY CK - PAONIA RES| 3.0| 90| 18|| 1.6| 68|| 2.6| 16.7|
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UNCOMPAHGRE - RIDGWAY| 69.9| 103| 84|| 64.5| 96|| 67.5| 83.0|
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RIFLE CK - RIFLE GAP | 9.3| M| 73|| 12.5| 92|| M| 12.2|
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FRYING PAN - RUEDI RE| 72.9| 107| 71|| 75.9| 107|| 70.8| 102.0|
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CIMARRON - SILVERJACK| 0.7| 14| 6|| 0.5| 9|| 5.1| 12.8|
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TAYLOR - TAYLOR PARK | 69.0| 103| 65|| 72.2| 106|| 68.1| 106.2|
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LOS PINOS - VALLECITO| 85.7| 123| 68|| 63.8| 93|| 68.5| 125.4|
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GREEN - FLAMING GORGE| 3113.0| 101| 83|| 3131.4| 102|| 3081.2| 3749.0|
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COLORADO - LAKE POWEL| 8010.8| 57| 34|| 8138.1| 56|| 14430.3| 23314.0|
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MEAN DAILY PEAK FLOW FORECASTS IN CFS
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The spring runoff flood potential will be re-evaluated in early
March and an updated product will be issued at that time.
LOCATION FLOOD FCST FORECAST FLOWS
FLOW DATE 90% 75% 50% 25% 10%
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YAMPA - STEAMBOAT SPRINGS 5923 2025-03-01
ELK - MILNER, NR 5916 2025-03-01
YAMPA - MAYBELL, NR 21200 2025-03-01
LITTLE SNAKE - LILY, NR 15271 2025-03-01
YAMPA - DEERLODGE PARK 20744 2025-03-01
WHITE - MEEKER, NR 8906 2025-03-01
SNAKE - MONTEZUMA, NR 2200 2025-03-01
TENMILE CK - FRISCO, N TE 2000 2025-03-01
STRAIGHT CK - LASKEY GULC 300 2025-03-01
EAGLE - GYPSUM, BLO 6000 2025-03-01
COLORADO - DOTSERO, NR 17000 2025-03-01
CRYSTAL - REDSTONE, NR, A 3200 2025-03-01
ROARING FORK - GLENWOOD S 13000 2025-03-01
COLORADO - CAMEO, NR 26000 2025-03-01
EAST - ALMONT 3100 2025-03-01
NF GUNNISON - SOMERSET, N 11000 2025-03-01
SURFACE CK - CEDAREDGE 1330 2025-03-01
GUNNISON - GRAND JUNCTION 21000 2025-03-01
DOLORES - RICO, BLO 1750 2025-03-01
DOLORES - DOLORES 6700 2025-03-01
SAN MIGUEL - PLACERVILLE, -999 2025-03-01
COLORADO - CO-UT STATE LI 46000 2025-03-01
SAN JUAN - PAGOSA SPRINGS 4600 2025-03-01
ANIMAS - DURANGO 10600 2025-03-01
ANIMAS - FARMINGTON 9000 2025-03-01
MANCOS - MANCOS, NR 810 2025-03-01
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CLIMATOLOGICAL OUTLOOK AND FORECAST CONDITIONS
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Not a lot of changes with regard to seasonal outlooks from the
last Spring Flood and Water Resources report. Sea surface
temperatures have remained cooler than normal which supports La
Nina conditions to persist. ENSO forecasts indicate weak La Nina
signals to continue through April, with a 66 percent chance of
shifting to a Neutral ENSO phase by March-May. Due to the current
ENSO phase and a persisting negative Pacific Decadal Oscillation
(PDO) signal, the Climate Prediction Center`s seasonal outlooks
resemble the "typical" weather patterns associated with La Ninas
through April; leaning wetter than normal across the Pacific
Northwest and likely below normal precipitation across the Desert
Southwest. As we transition out of winter and into spring, the
areas of likely warmer and drier conditions shift north, and
spread across the Upper Colorado River Basin. These outlooks would
suggest less precipitation and warmer temperatures during the
beginning of snowmelt season. However, outlooks extending into
summer maintain that northward trajectory of warm and dry
conditions, such that equal chances of warm vs cool or dry vs wet
conditions nudge over eastern Utah and western Colorado during
the monsoon.
On a shorter-scale timeframe, sub-seasonal outlooks favor a return
of AR activity across northern California and Central California
in early March. Guidance also suggests active AR patterns to
expand along the California coast by week 4. If these models`
forecasts verify, then we may expect Pacific moisture returning
across the Upper Colorado Basin in early March and, again, by mid-
March. CPC`s 8 to 14 Day Precipitation Outlook follows suite,
with likely above normal precipitation March 6th through 12th
along the Pacific Coast with a 40 to 50 percent chance of above
normal precipitation reaching the Upper Colorado Basin.
$$