Avalanche in Idaho, January 20, 2019

Area Forecast Discussion
National Weather Service Pocatello ID
305 AM MST Sun Jan 20 2019

.SHORT TERM...Today through Tuesday night.
Upper trof in the Pacific will move east today and extensive
Pacific moisture will continue to stream into southeast Idaho
with snow and rain. Snow levels will range between 5 and 6
thousand feet through midnight tonight so precipitation expected
to be rain in Snake River Plain. Winter Weather Advisories are in
effect for the central mountains and upper snake highlands through
tonight and in the southern highlands this evening through Monday
morning. Travel over mountain passes especially is expected to be
hazardous for the next 24 hours. Snow levels will drop to valley
floors early Monday morning after the cold front with the system
pushes east and there is still the possibility of 1 to 3 inches of
snow in the Snake River Plain on Monday. Models are differing
significantly on the effect in the Pocatello to Idaho Falls
interstate corridor however. Precipitation will linger Monday in
the southern highlands then taper off Monday night with Tuesday
expected to be dry and snow showers moving back into the mountains
Tuesday night with very light accumulations. Temperatures will be
very warm today with significant cooling down Monday and Tuesday
to seasonal normals and even below normal by Tuesday.
GK

.LONG TERM...Wednesday through next Sunday
Highlights:
- Mountain snow for middle of next week
- High pressure leads to a calmer weather pattern late next week
- Temperatures at or slightly above seasonal averages

The broad trough of low pressure set up to our southeast by the
digging early week system will act to steer a new disturbance
through our area beginning Wednesday. This British Columbia Clipper
will be quickly pulled through the area from northwest to southeast.
This looks to set up a precipitation shadow effect over the Snake
Plain, while focusing the much of the snow through the central
mountains and especially along the eastern highlands. It is over the
eastern highlands that snow will then remain focused through at
least Thursday as the moisture stream continues to hold. From about
I-15 and west will begin to dry out heading towards the weekend.

Models are trending a little less towards a big ridge directly
overhead, as we have seen with previous model runs, but there is
still some potential. For now will keep the end of the week and
weekend dry, but look for possible changes to this if we stay in the
northwesterly flowing moisture stream.
TAX

&&

.AVIATION...The primary moisture stream, fueling much of the
remaining rain and snow showers is beginning to shift to the north.
This means that SUN/IDA/DIJ still have the best chance at
precipitation this morning, but with temperatures warming it may
switch over to rain.

Recent satellite images show that beneath the obscuring cirrus, we
can discern a stratus layer primarily over southeastern Idaho. While
not currently impacting PIH or BYI, we cannot rule out a brief
ceiling reduction. Otherwise, current VFR conditions are expected to
hold until the next wave pushes moisture and precipitation back to
the area later tonight. This will initially fall as rain, but as
colder air moves back in late tonight into Monday, a transition to
snow should occur. This will bring areawide restrictions stretching
through the day Monday.
TAX

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 5 PM this afternoon to 11 AM MST
Monday for IDZ056>063.

Winter Weather Advisory until 5 AM MST Monday for IDZ064>066-
071>074.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE POCATELLO ID
739 AM MST SUN JAN 20 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0700 AM     SNOW             7 NNW KETCHUM           43.77N 114.42W
01/20/2019  E3.1 INCH        BLAINE             ID   MESONET

            CHOCOLATE GULCH SNOTEL 6440 MSL. 17-HOUR TOTAL.

0700 AM     HEAVY SNOW       16 WSW KETCHUM          43.60N 114.67W
01/20/2019  E6.1 INCH        BLAINE             ID   MESONET

            DOLLARHIDE SUMMIT SNOTEL 8421 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             21 NW KETCHUM           43.88N 114.67W
01/20/2019  E2.6 INCH        BLAINE             ID   MESONET

            GALENA SNOTEL 7440 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             22 NW KETCHUM           43.87N 114.72W
01/20/2019  E2.2 INCH        BLAINE             ID   MESONET

            GALENA SUMMIT SNOTEL 8782 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             10 E KETCHUM            43.72N 114.17W
01/20/2019  E2.6 INCH        BLAINE             ID   MESONET

            HYNDMAN SNOTEL 7440 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             1 WSW ISLAND PARK       44.42N 111.38W
01/20/2019  E4.4 INCH        FREMONT            ID   MESONET

            ISLAND PARK SNOTEL 6293 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             11 NNE KETCHUM          43.82N 114.27W
01/20/2019  E5.4 INCH        BLAINE             ID   MESONET

            LOST WOOD DIVIDE SNOTEL 7903 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             5 WSW VICTOR            43.57N 111.22W
01/20/2019  E5.8 INCH        BONNEVILLE         ID   MESONET

            PINE CREEK PASS SNOTEL 6720 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             17 SW MACKAY            43.73N 113.83W
01/20/2019  E2.2 INCH        CUSTER             ID   MESONET

            SMILEY MOUNTAIN SNOTEL 9520 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             33 E BLACKFOOT          43.22N 111.68W
01/20/2019  E2.4 INCH        BINGHAM            ID   MESONET

            SHEEP MOUNTAIN SNOTEL 6571 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             19 ENE HAILEY           43.63N 113.97W
01/20/2019  E4.4 INCH        BLAINE             ID   MESONET

            SWEDE PEAK SNOTEL 7641 MSL. 17-HOUR TOTAL.

0700 AM     SNOW             26 WNW KETCHUM          43.80N 114.85W
01/20/2019  E5.5 INCH        BLAINE             ID   MESONET

            VIENNA MINE SNOTEL 8963 MSL. 17-HOUR TOTAL.

&&

VALLE