Areal Flood Warning 2, NWS Elko, NV

Area Forecast Discussion
National Weather Service Elko NV
1228 PM PST Tue Feb 7 2017

.SYNOPSIS...A long stretch of Pacific moisture will bring heavier
rains and some mountain snows to the region through the week.
Temperatures will be warmer than normal. Some flooding is
possible.

&&

.UPDATE...Expired the WSW for northern Elko County and the
Ruby/East Humboldt Range. Widespread snow has ended or changed to
rain for all valley locations. Snow showers will contiue in the
mountains, but snowfall accumulations will be under warning
criteria.

&&

.PREV DISCUSSION... /ISSUED AT 233 AM /

SYNOPSIS...A long stretch of Pacific moisture will bring heavier
rains and some mountain snows to the region through the week.
Temperatures will be warmer than normal. Some flooding is
possible.

SHORT TERM...Today through Thursday. Atmospheric river from
north of Hawaii into the Great Basin will be the main feature of
the period. The Sierra, of course, block much of the flow, but
enough will proceed over the top to give a good potential for
flooding. The ample snowpack presents another problem with much
above normal SWE. In addition, HUGE zonal jet buckles and turns
anti-cyclonic over the western interior CONUS for serious warming
south of the jet. The jet, at 120 knots, will become a 160-180
knot jet further inland, enhancing the western CONUS ridge.
Surface winds will blow near 25 mph today with gusts to 40-45 mph
over certain summits/passes. Mostly valleys will remain in the 35
mph gust range.

Biggest issue is hydrology. See section below.

Much above normal surface temps through the period with highs
today in the mid 40s into the low 50s by Thursday for the
north and east...mid 50s northwest. For central Nevada
valleys...up into the low 60s by Thursday. Lows will not likely
dip down to freezing anywhere, with buckling upper flow and
clouds/rain.

LONG TERM...Thursday night through Tuesday

Thursday night through Friday. A cold front will slowly transit
across the silver state. This will provide for considerable
moisture that should cause ample showers. The entrenched warm air
should keep the precipitation mostly as rain slowly transitioning
to snow. However by the time snow levels will drop to allow for
accumulation in the valleys most of the moisture should have moved
out of the silver state. This should not allow for any significant
snow accumulation in the valleys. The mountains on the other hand
should receive a long period of accumulation which will be over
several inches.

Saturday. The models are still in agreement on an open trof or
closed low dropping generally SE near/through eastern Nevada. This
should induce a fairly cool northerly flow across Nevada. This
will also serve to scour out the moisture with showers during the
morning giving away to dry conditions by the afternoon.

Saturday night through Tuesday. A ridge is depicted building
across the Great Basin following the passage of the closed low.
This will keep the silver state dry with no pertinent weather.

AVIATION...A storm system translating across the silver state is
bringing low ceilings and rain showers to all terminals. The low
ceilings can reach down to MVFR or IFR which may also lead to
mountain obscurations. Strong gusty winds from the south to
southwest will accompany the passage of this system.

HYDROLOGY...warm temps, winds, and rains on snow pack will cause
localized lowland flooding. In addition, small streams area
already running high and some could exceed banks and flood stages
where those are established.

&&

.LKN WATCHES/WARNINGS/ADVISORIES...None.

&&

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