164 
fxus65 kslc 210842 
afdslc 


Area forecast discussion 
National Weather Service Salt Lake City Utah 
242 am MDT sun Mar 21 2010 


Synopsis...high pressure will build across the region today. The 
next Pacific storm system will move into the Great Basin Monday 
and Tuesday. 


&& 


Discussion...early morning water vapor imagery and objective 
analysis show a middle level ridge centered across the Great 
Basin. Models forecast this ridge to slide eastward during the 
day today allowing a southwesterly flow aloft to overspread the 
forecast area. Increased mixing associated with this flow along 
with continued warming aloft should allow maximum temperatures to exceed 
climatology by 5 to 10 degrees across most areas. 


Shortwave trough currently near 130w forecast to push inland and 
through the northern rockies late today through Monday...pushing a 
shallow cold front into northern Utah Monday morning. Precipitation 
threat appears limited as this boundary crosses northern Utah Monday 
until secondary trough digs south into the area late Monday 
through early Tuesday. Precipitation during this time should be 
focused along frontal boundary as it crosses central/southern 
Utah...with a lesser threat across the north associated with upper 
cold pool. 


00z models have trended much faster with pushing this trough out 
of the area late Tuesday as middle level ridging quickly re-builds 
across the Great Basin. As such have trimmed back probability of precipitation for later 
Tuesday through Wednesday across most of the area. 


Model guidance varies quite a bit beyond middle-week with respect to 
timing of shortwave features forecast to pass through the region. 
As such have adjusted going pop grids toward climatology for the 
latter portion of the period. 


&& 


Aviation...no operational weather concerns expected at kslc tonight 
with VFR conditions and any ceilings well above 7000 feet. South winds may 
become gusty by late morning and will prevail into the afternoon 
with a late shift around 20-22z to northwest. There is a 30 percent 
possibility of no shift at all. 


&& 


Slc watches/warnings/advisories... 
Utah...none. 
Wyoming...none. 
&& 


$$ 


Seaman/Kruse 


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