Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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FXUS65 KSLC 290858
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
258 AM MDT SUN MAY 29 2016

.SYNOPSIS...A low pressure system moving slowly east through the
desert southwest will serve to keep unsettled conditions across
portions of Utah through Monday. Strong high pressure aloft will
follow for the middle and latter portions of the upcoming week.

&&

.SHORT TERM (THROUGH 12Z TUESDAY)...
Water Vapor loop shows a closed low nearing Southern California.
AMDAR 400-200MB wind observations place a 75-105kt Northwesterly
jet into the Pacific Northwest. A second Southwest jet of similar
magnitude was located from Baja California into the plains.
GOES/HRRR/00Z KSLC RAOB indicate the precipitable water value
ranges from 0.25"-0.40" mountains to 0.50"-0.75" most valleys.

The warming trend continues today.

Short range ensembles indicate plenty of instability through the
short term period, even lasting into the overnight hours. As the
closed low feature makes its way into Arizona by Tuesday morning,
deformation axis to its north will enhance diurnal convection along
the higher terrain.

While Central and portions of Northern Utah and Southwest Wyoming
will be favored for development this afternoon lingering into
tonight, a much more stable airmass is expected to impinge from the
Northwest tomorrow afternoon and evening. No PoPs mentioned for
Memorial day SLC northward, but Southern Utah will be favored as the
deformation/instability axis shifts Southeast.

Memorial day expecting a slightly better chance for heavy showers
and storms across the parks of Southern Utah. Cloud bases are still
rather high, and there is minimal warm cloud depth, however storm
motion is quite weak and precipitable water values are elevated.

.LONG TERM (After 12Z Tuesday)...
The departing cutoff low continues to progress eastward across
the far Desert Southwest as high amplitude ridging continues to
build in off the West Coast. Under northwest flow aloft, mid-level
mixing ratios begin a gradual decline especially noted across
northwest Utah. While still maintaining better moisture across
south-central and southeast Utah, small shortwave features rotate
around the ridge by late week to provide more instability for high
terrain driven convection. Kept very low mention of PoPs in the
extended and only left mention in the high terrain of eastern
Utah.

By next weekend, global models along with ensemble model runs, are
in agreement with the next upper level trough feature to develop off
the coast of Southern California to break down the ridge and bring a
return of moisture to the Great Basin region. Streaming in southwest
flow aloft and advecting in sufficient amounts of precipitable
water, another unsettled weekend looks to be in store for the first
part of June.

&&

.AVIATION...Southerly winds expected at KSLC terminal before
switching to the north by 19Z. Isolated showers after 21Z could
cause winds to become erratic and variable, before a diurnal switch
to the south by 04Z. Ceilings expected to remain at or above 8000 ft.

&&

.FIRE WEATHER...The warming trend continues today.

Isolated to scattered convection can be expected today and tomorrow
across the region. In addition to the threat of lightning,
convection is likely to contain dry microburst wind gusts and
wetting rain.

Gusty Northwest winds are possible Monday into Tuesday as this
system departs.

First significant warming/drying trend of the year on tap during
the second half of the work week as a ridge builds in.

&&

.SLC Watches/Warnings/Advisories...
UT...None.
WY...None.
&&

$$

SHORT TERM/FIRE WEATHER...Rogowski
LONG TERM/AVIATION...Dewey

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http://weather.gov/saltlakecity

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



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