Area Forecast Discussion
Issued by NWS Salt Lake City, UT

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

000
FXUS65 KSLC 190316
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
916 PM MDT Sat Mar 18 2017

.SYNOPSIS...A very mild southwest flow will continue into early
next week. A more active pattern is expected to develop by mid
week.

&&

.DISCUSSION...Shallow cold front working SE across the northwest
deserts will continue to phase towards the central Wasatch Front
this eve before stalling and washing out. Mid level baroclinicity
upstream over the NW corner of the state and weak elevated
instability coincident with a weakening short wave lifting across
NE Nevada has allowed for scattered convective showers, locally
gusty winds (due to dry low levels), and prolific cloud cover over
the NE`rn 1/4 of the state. Trended grids to follow recent trends
this eve.

A bigger take away from today were the anomalously warm temps.
KSLC shattered the max temp record for the date, reaching
79F...one degree short of tying the all time March record. Several
other records were realized, namely over northern/western UT.

Moving forward, the aforementioned short wave will slide east
across southern ID tonight, maintaining generally a slight chance
of light precip across the UT/ID border region. Made minor
adjustments to grids for far northern UT...increasing cloud cover
and lowering PoPs south of Brigham City. As a whole, the area will
remain very mild, and largely dry. Previous discussion below...

PREVIOUS DISCUSSION...Another disturbance will ride across the
flattened ridge through Idaho Sunday afternoon which could set
off a few showers along the Idaho border late in the day.
Temperatures across northern Utah will be down about 3-6 degrees
Sunday compared to today, while only 1-3 degrees cooler in the
south.

The EC and GFS show a weak disturbance associated with a broad
area of warm advection moving across the Great Basin and central
Rockies Monday afternoon. The low levels remain rather dry looking
so once again have kept the main threat of showers and
thunderstorms across the higher elevations.

A stronger system will approach the western CONUS Tuesday and
south winds are expected to increase with more cooling expected in
the south than in the north as this system will be farther south.

.LONG TERM (After 00Z Wednesday)...The longwave trough developing
along the West Coast is expected to move inland midweek, splitting
as it does so. One piece of energy is progged to move through the
Desert Southwest, and another through the Northern Rockies. This
splitting flow, combined with the general southwest flow aloft which
is unfavorable for moisture transport into our area, should somewhat
dampen the chances for widespread precipitation over our area.
Nevertheless, expecting a big cooldown in temperatures to near or
below normal with a chance of light precip at times. The precip
focus will initially be over northern UT Tues/Wed, then central &
southern UT later Wed and Thursday.

A cold front is expected Thursday, with the GFS showing 700MB temps
dipping as low as -8C over northern UT. This could support graupel
or snow showers to valley floors, with accumulating snow possible in
the mountains. Timing will play a key role in whether frozen precip
is an impact. Currently, the model consensus has the cold air
arriving during the day Thursday, which would result in limited
impacts.

Global models are in great agreement with a continued active pattern
for the remainder of the week and into the weekend. Brief ridging is
expected Friday, following by a strong closed low moving into the
Great Basin by late Friday into Saturday. This would bring a
continued period of near to below normal temperatures and a threat
of widespread precipitation across the forecast area.


&&

.AVIATION...For the KSLC terminal...A weak boundary tonight will
bring a 60% chance of a shift to light northwest winds about 6-8z,
with southerly winds likely returning a few hours later. VFR
conditions will prevail under thickening mid level cloud cover.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

$$

DISCUSSION/AVIATION...Merrill
PREVIOUS DISCUSSION...Struthwolf/Van Cleave

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.