Area Forecast Discussion
Issued by NWS Salt Lake City, UT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 30
FXUS65 KSLC 121709

Area Forecast Discussion
National Weather Service Salt Lake City UT
1009 AM MST Tue Dec 12 2017

.SYNOPSIS...Strong and persistent high pressure aloft will remain
the dominant weather feature across the western states through the
end of the work week.


.DISCUSSION...Strong high pressure remains over much of the
western CONUS this morning, leading to persistent low level
inversion conditions across Utah. Widespread fog and stratus has
formed across the valleys of northern Utah, and has spread
overnight and this morning much further than it had earlier in the
event. This includes the west desert out to Wendover, and most of
the Wasatch Front. While there will probably be some diurnal
fluctuation in the areal coverage of these clouds, for the most
part these conditions should remain in place through the work

One possible source of minor relief is a weak wave that is
forecast to move through Colorado on Wednesday night. With some
cooling aloft over Utah, this should weaken the inversions,
though is not currently expected to be strong enough to transport
much of the pollution away from the urban areas. Otherwise, will
take a closer look at the stronger shortwave trough that may move
through Utah on Friday night and Saturday, and which seems to be
gaining some model consistency as it gets closer.

Updated the forecast this morning to extend the fog and stratus
out to Wendover. Also updated to cool today`s maximum
temperature forecast, including Salt Lake City. Will keep an eye
on the extent of fog/stratus/snow flurries to see if any tweaks
need to be made, but otherwise stagnant conditions should make for
a continued stagnant forecast.


.AVIATION...Visibilities at the SLC terminal today should
generally bounce between 1/2SM and 2SM through the day, with
ceilings likely remaining below 1000. There is only a 20 percent
chance that conditions will improve to MVFR levels between 19Z and
23Z. Dense fog, with visibilities 1/4SM or less, will likely
return between 01Z and 06Z.





For more information from NOAA`s National Weather Service visit...

For frequently asked questions about the Area Forecast Discussion
visit... is the U.S. government's official web portal to all federal, state and local government web resources and services.