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Area forecast discussion
National Weather Service Salt Lake City Utah
1010 am MDT Thursday Apr 24 2014
Synopsis...a weak system will cross northern Utah today. A mild
southwesterly flow will develop tonight and increase Friday
ahead of the next Pacific storm. This system will cross the
region late Friday through Saturday.
Discussion...a weak warm front is bringing clouds and local light
showers to the far northern County Warning Area today while a mild southwesterly flow develops
across the remainder of the area.
This is downstream from a broad trough in the eastern Pacific that is
forecast to eventually swing inland Friday and across the Great Basin
on Sat. The frontal boundary gets pushed into northwestern Utah after
midnight tonight then stalls as the main upper trough digs down the
coast and the upper level flow backs to more southerly over the County Warning Area.
This deepens a surface low over southern Utah and generates fairly strong
south winds south of the low during the day tomorrow. Speeds could
locally reach marginal warning levels but overall should be in the
advisory range and am will likely issue this with the afternoon
forecasts. Speeds should drop off once precipitation starts. It should
begin across the northwest by tomorrow morning and slowly increase through
the day becoming widespread during the evening and finally developing
across all of western Utah after midnight.
Most of the precipitation occurs before the coldest air with this trough
arrives. Expect sufficient snowfall in the mountains to warrant an
advisory but the main impact would be generally above about
7000-8000 feet starting late Friday night or Sat morning. So do not
plan on issuing any winter weather highlight today.
The precipitation winds down Sat night and the upstream wave for later
in the weekend into Monday still appears weak.
Will issue a brief update to raise probability of precipitation a little across the far
north for the rest of today and reduce sky cover over the south.
Aviation...operational weather concerns will remain limited at the
kslc terminal through the valid taf period. Occasional gusty
southerly winds are expected to shift to the northwest between 19
and 21z. There is a 20 percent chance winds will remain southerly
through the day.
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http://weather.Gov/saltlakecity (all lower case)
For frequently asked questions about the area forecast discussion
http://weather.Gov/saltlakecity/general/afd_faqs.Php (all lower case)