The Weather Prediction Center

College Park, MD


Storm Summary Message



Storm Summary Number 1 for Northwestern U.S. Winter Storm
NWS Weather Prediction Center College Park MD
100 PM PST Fri Jan 12 2024

...Areas of moderate to locally heavy snowfall continue through
the Rockies, Great Basin, and Pacific Northwest, with a renewed
round of snow expected with an incoming Pacific System Saturday...

Winter Storm Warnings are in effect for portions of the interior
Pacific Northwest, northern/central Great Basin, northern/central
California, and the northern/central Rockies.

Blizzard Warnings are in effect for portions of southern Idaho.

Ice Storm Warnings are in effect for portions of western Oregon.

Winter Weather Advisories are in effect for portions of the
northern Rockies, central Great Basin, and northern/central
California.

Wind Chill-related Warnings and Advisories are in effect for
portions of the interior Pacific Northwest, northern Great Basin,
and northern and central Rockies.

Winter Storm Watches are in effect for portions of northwestern
Oregon and southwestern Washington.

Flood Watches are in effect for coastal southern Oregon and
northern California.

For a detailed graphical depiction of the latest watches, warnings
and advisories, please see www.weather.gov

At 1200 PM PST...A quasi-stationary frontal boundary was analyzed
through portions of the central/northern Rockies and into the
Great Basin and Pacific Northwest, tracing a path from
southeastern Wyoming through southern Idaho and towards the
Pacific Coast of northwestern Oregon. Surface observations
indicated a colder, sub-freezing air mass resided along and to the
north of this boundary and along, east of the Cascades. An even
colder, Arctic air mass with temperatures well below zero was in
place in the High Plains along the Rocky Mountains, beginning to
slowly pass through the mountains and into the northern Great
Basin. National Weather Service Doppler Radar showed several areas
of moderate to locally heavy snowfall occurring across portions of
the Wasatch mountains and northern Utah, southwestern Idaho
including the Treasure Valley, the Blue Mountains of northeastern
Oregon, and the Oregon Cascades. The precipitation remained rain
so far along lower elevations of the Pacific Northwest to the west
of the Cascades. Surface observations also indicated gusty winds
between 20-30 knots, particularly in vicinity of the
quasi-stationary frontal boundary.

...Selected preliminary Storm Total Snowfall in inches from 700 PM
PST Thu Jan 11 through 100 PM PST Fri Jan 12...

...IDAHO...
DEADWOOD RESERVOIR 12 NNE            11.2                    
FEATHERVILLE                          9.0                    
GRANGEVILLE                           8.0                    
LEWISTON 1 SE                         7.0                    
NEW MEADOWS 2 NNW                     6.0                    
OROFINO 5 NE                          6.0                    
STANLEY                               4.6                    
ALMO                                  4.0                    
SODA SPRINGS                          3.0                    
BOISE 1 N                             2.0                    

...MONTANA...
BIGFORK 3 ENE                         9.5                    
HERON 3 NW                            8.1                    
COLUMBIA FALLS                        7.0                    
THOMPSON FALLS 1 WSW                  5.2                    
GRANTSDALE 2 ENE                      5.1                    
HELENA 2 W                            4.7                    
NYE 14 W                              3.0                    
BILLINGS 3 NNE                        2.0                    

...OREGON...
ISLAND CITY 4 NNW                    13.0                    
JOSEPH                                5.5                    
ELGIN 10 N                            5.0                    
PILOT ROCK                            3.0                    
SISTERS 2 WNW                         3.0                    
JOHN DAY 1 NW                         2.5                    

...WASHINGTON...
STEVENS PASS                         15.0                    
WENATCHEE 1 WSW                      11.4                    
ANATONE 2 S                           7.0                    
WHITE SALMON 18 N                     7.0                    
SEQUIM 2 ESE                          6.0                    
DAYTON 9 NE                           4.5                    
PORT ANGELES                          4.0                    

...Selected preliminary Peak Wind gusts in miles per hour earlier
in the event...

...IDAHO...
MARION 17 WSW                          73 MESONET            
POPLAR 2 WSW                           61                    
JEROME 3 E                             60                    
IDAHOME 2 NW                           57 MESONET            
ALTON 4 SW                             56                    
COLD WATER 2 WSW                       56                    
POCATELLO 7 E                          55                    

...OREGON...
VAN 14 ENE                             68 MESONET            
DIAMOND 10 NE                          61 MESONET            
BURNS                                  43                    


Additional snowfall in vicinity of the frontal boundary will
continue through Saturday morning, with the highest totals focused
on the Oregon Cascades, southwestern Idaho, and the Wasatch
mountains of Utah. Here, there is high probability (70-90%) of 6
inches or more of additional snow. Lighter totals of around 1-4"
are expected for surrounding lower elevations. Strong, gusty winds
will continue to lead to blizzard conditions across southern
Idaho. An approaching upper-level shortwave and accompanying
surface low pressure/frontal system over the Pacific will reach
the region early Saturday, bringing a renewed round of moisture
coincident with the frontal boundary continuing to creep
southward. This will lead to additional snowfall spreading both
further southward into California, the Great Basin, and the
central Rockies, and also bring wintry weather to lower elevations
of the coastal Pacific Northwest. The highest snow totals are
expected in the Oregon Cascades, Sierra, Wasatch mountains of
Utah, and central Rockies in Colorado, where there is at least a
moderate probability (40-60%) of more than a foot of snow through
Monday morning. There is a high probability (70-90%) lower
elevations of the northern/central Great Basin from eastern Oregon
into southern Idaho and northern Nevada/Utah will see 4+" of snow,
locally up to a foot. Lower elevations of southwestern Washington
and Oregon to the west of the Cascades can expect areas of
snowfall, generally between 1-4", as well as potentially
significant icing (accretions up to 0.5"), most likely for the
southern Willamette Valley. In addition to the wintry
precipitation, bitterly cold wind chills will continue for areas
of the northern interior Pacific Northwest/Great Basin, and there
is also the risk of flooding with rain along the southern Oregon
and northern California Pacific Coast. The associated upper-level
system is also expected to bring winter impacts to the Mid-South
by late Sunday, and potentially the Northeast next
Tuesday-Wednesday. 

The next Storm Summary will be issued by the Weather Prediction
Center at 100 PM PST Sat Jan 13 2024. Please refer to your local
National Weather Service office for additional information on this
event.

Putnam




Last Updated: 412 PM EST FRI JAN 12 2024