Severe Thunderstorm Warning 1, NWS Salt Lake City, UT

809 
WWUS55 KSLC 082143
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
343 PM MDT SAT APR 8 2017

UTC011-029-057-082200-
/O.CON.KSLC.SV.W.0001.000000T0000Z-170408T2200Z/
Weber UT-Davis UT-Morgan UT-
343 PM MDT SAT APR 8 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM MDT
FOR CENTRAL WEBER...NORTHEASTERN DAVIS AND WEST CENTRAL MORGAN
COUNTIES...

At 342 PM MDT, Doppler radar indicated a severe thunderstorm capable
of producing quarter size hail and damaging winds in excess of 60 
mph. This storm was located near South Ogden, or near Ogden, moving 
northeast at 40 mph.

Locations impacted include...
Ogden, Layton, Morgan, Roy, Kaysville, South Ogden, Washington
Terrace, Riverdale, South Weber, Uintah, Fruit Heights, Huntsville,
Mountain Green, Eden, Stoddard, Liberty, Peterson, Hill Air Force
Base, Pineview Reservoir and East Layton.

At 342 PM hail to the size of quarters was reported in South Weber. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Severe thunderstorms produce damaging winds, destructive hail, deadly
lightning and very heavy rain. For your protection move to an
interior room on the lowest floor of your home or business. Heavy
rains flood roads quickly so do not drive into areas where water
covers the road.

This storm is capable of producing a significant amount of hail. Hail
may accumulate on area roads resulting in dangerous travel
conditions.

&&

LAT...LON 4102 11191 4119 11204 4138 11182 4106 11160
TIME...MOT...LOC 2142Z 240DEG 33KT 4120 11186 

$$

MPS

597 
WWUS55 KSLC 082156
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
356 PM MDT SAT APR 8 2017

UTC011-029-057-082206-
/O.EXP.KSLC.SV.W.0001.000000T0000Z-170408T2200Z/
Weber UT-Davis UT-Morgan UT-
356 PM MDT SAT APR 8 2017

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL WEBER...NORTHEASTERN
DAVIS AND WEST CENTRAL MORGAN COUNTIES WILL EXPIRE AT 400 PM MDT...
        
The storm which prompted the warning has weakened below severe limits
and exited the warned area. Therefore the warning will be allowed to
expire.

LAT...LON 4102 11191 4119 11204 4138 11182 4106 11160
TIME...MOT...LOC 2156Z 240DEG 33KT 4125 11173 

$$

MPS

Area Forecast Discussion
National Weather Service Salt Lake City UT
1223 PM MDT Sat Apr 8 2017

.SYNOPSIS...A cold upper level trough will advance east across
the Great Basin this weekend. A drier west to southwest flow is
expected for the first half of next week with a warming trend.

&&

.DISCUSSION...Precip with snow falling down to roughly 6000ft on
average remains focused along the remnant baroclinic zone roughly
from EVW to DPG in northern Utah, while numerous rain and high
elevation snow showers persist across SW Utah associated with an
ejecting short wave. Over the next few hours expecting both of
these areas to see a net downward trend in precip with partial
clearing across the western half of area as a mid level dry slot
punches NE across the area, this in advance of the next and more
potent cold front developing now over Nevada. Have trimmed PoPs
substantially across most western valleys through mid afternoon in
latest update, though maintained elevated PoPs along the
aforementioned baroclinic zone in the north.

The surface pressure trough from this first front has roughly
stalled with southern extent stretching across central UT at this
time. South of this trough a suitable S-N oriented MSLP gradient
coupled with H7 winds of 40-55kt continues to provide support for
strong and gusty SW winds across the southern tier. Have added the
Sevier/Sanpete Valleys to going Wind Advisory suite, as widespread
wind gusts into the upper 40s and possibly a bit higher remain a
potential into early evening.

Upstream the next Pacific trough continues to translate east
across NorCal with a strong cold core in place. Thermal packing
continues to strengthen along the leading edge baroclinic zone
over central Nevada at this hour, and a nice cold frontal
signature is taking form in both satellite/radar in the Battle
Mtn NV area. Have not made any changes to afternoon forecast as
this front should reach the ENV area by 2pm, and the Wasatch
Front by 4-5pm.

This front will be trending increasingly frontogenic as it
progresses east across the area this afternoon, with mid to late
afternoon timing aiding thermal packing. Expecting the potential
for semi- organized thunderstorms along this front (marginal
threat for severe winds/hail), with modest instability, strong low
level forcing, and jet support aloft driving deeper cores.
Additionally, cold advection in wake of its passage coupled with
high PI potential should be sufficient to lower snow levels to
lower valley locales across the northern half of the area by the
evening hours. Will address any need to expand Winter Weather
Advisories into the Wasatch Back and Southwest Wyoming for the
afternoon package. The ones in place remain on track.

The cold core of the upper trough will settle over northern Utah
tonight, with nice westward tilt of CAA with height as it does
so. Widespread and heavy at times snowfall will continue in the
northern mountains into early Sunday morning (especially those
favored by NW flow), prior to turning more showery towards dawn.
Valleys will likely see up to a few inches of wet snow on the
benches by Sunday morning, primarily on grassy surfaces.

Heights will begin to build from the south Sunday.

&&

.AVIATION...VFR conditions are expected to prevail into the early
afternoon at the SLC terminal with cigs near 7000 feet AGL.
Precipitation is expected to develop late this afternoon with the
passage of a cold front between 22Z and 00Z. Initial precipitation
type will be rain with a changeover to snow by 03Z. Low-end VFR to
high-end MVFR will prevail in rain with IFR conditions becoming
predominant in snow. Little snow accumulation is anticipated.
Southeast winds are expected through much of the afternoon, shifting
to the northwest with the passage of the cold front.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Wind Advisory until 8 PM MDT this evening for UTZ013>016-019>021.

     Winter Weather Advisory until 9 AM MDT Sunday for UTZ008-009.

     Winter Weather Advisory until 9 AM MDT Sunday for UTZ007.

WY...None.
&&

Merrill/Traphagan

For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity

For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php

Hazardous Weather Outlook
National Weather Service Salt Lake City UT
609 AM MDT Sat Apr 8 2017

UTZ001>016-019>021-517-518-WYZ021-091215-
Cache Valley/Utah Portion-Northern Wasatch Front-
Salt Lake and Tooele Valleys-Southern Wasatch Front-
Great Salt Lake Desert and Mountains-Wasatch Mountain Valleys-
Wasatch Mountains I-80 North-Wasatch Mountains South of I-80-
Western Uinta Mountains-Wasatch Plateau/Book Cliffs-
Western Uinta Basin-Castle Country-San Rafael Swell-
Sanpete/Sevier Valleys-West Central Utah-Southwest Utah-
Utahs Dixie and Zion National Park-South Central Utah-
Glen Canyon Recreation Area/Lake Powell-Central Mountains-
Southern Mountains-Southwest Wyoming-
609 AM MDT Sat Apr 8 2017

This Hazardous Weather Outlook is for the western two thirds of
Utah and southwest Wyoming.

.DAY ONE...Today and Tonight

Strong south winds ahead of a cold front will continue across
mainly the southern half of the outlook area into this evening.

Rain with snow above about 6500 to 7500 feet will increase across
the northern and central outlook area through the morning before
turning showery around midday. The snow will impact travel on any
roadways above about 7000 feet this morning.

Winds will increase across the northwest deserts late today as
another round of rain and snow moves into the outlook area. This
new round of precipitation will spread across much of the
northern and central outlook area this evening with snow levels
falling to the valley floors.

Winter driving conditions will impact travel tonight on all
northern and central routes above about 6000 feet. Valley routes
should stay mostly just wet with some minor slushy accumulation
possible.

Some of the rivers and streams across northern Utah are expected
to run high due to the combination of recent warm temperatures and
expected rainfall. Minor flooding will be possible along the
headwaters of both the Little Bear River and South Fork of the
Ogden River this afternoon through tonight.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Snow showers across the northern and central mountains and the
western valleys will taper off Sunday morning. Local winter
driving conditions could still impact travel early Sunday with
conditions improving by midday.

Gusty south winds could develop across the western outlook area
again late in the week ahead of the next spring storm.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

For more information from NOAA/s National Weather Service visit...
http://weather.gov/saltlakecity

For information on potential road travel impacts visit...
http://www.udottraffic.utah.gov/roadweatherforecast.aspx

Special Weather Statement
National Weather Service Salt Lake City UT
320 PM MDT SAT APR 8 2017

UTZ002-007-082145-
Wasatch Mountains I-80 North UT-Northern Wasatch Front UT-
320 PM MDT SAT APR 8 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL WEBER AND
NORTHEASTERN DAVIS COUNTIES UNTIL 345 PM MDT...

At 320 PM MDT, National Weather Service doppler radar indicated a
strong thunderstorm OVER Syracuse, or 8 miles west of Layton...moving
northeast at 40 mph.

penny size hail and winds in excess of 40 mph will be possible.

Locations impacted include...
Ogden, Layton, Roy, Clearfield, Kaysville, Syracuse, Clinton, North
Ogden, South Ogden, Washington Terrace, Riverdale, Hooper, South
Weber, Marriott-Slaterville, Uintah, West Haven, West Point, Farr
West, Harrisville and Sunset.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

This storm is capable of producing a significant amount of hail. Hail
may accumulate on area roads resulting in dangerous travel
conditions.

&&

LAT...LON 4098 11212 4111 11221 4133 11195 4106 11189
TIME...MOT...LOC 2120Z 237DEG 35KT 4111 11210

MPS