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Area forecast discussion 
National Weather Service Boise Idaho
1007 am MDT Thursday may 28 2015

Discussion...area will remain under cyclonic flow around upper
low positioned along the Idaho/Wyoming this morning. Morning Boise
sounding showing some drying in middle-levels /h5-h7/ compared to
yesterday. Winds are northwest throughout layer and will pick up at the
surface this afternoon in open valleys. Shower and thunderstorm
threat for this afternoon will focus over higher terrain east of a
line from McCall-Idaho City-Jerome...and the mountains of Baker
County. Current forecast has this well covered so no updates for
this morning.


Aviation...VFR. Few to scattered middle level clouds...becoming clear
overnight. Isolated showers and thunderstorms developing east of a
McCall-Idaho City-Jerome line this afternoon and evening. Surface
winds...variable 12 kts or less. Winds aloft at 10k feet mean sea level...northwest 5-
10 kts...becoming light and variable by 29/12z...before turning SW
at 5-15 kts by 30/00z.


Previous discussion...
short through upper level low centered
over eastern Idaho will continue to move east as an upper ridge
builds in from the west. Moisture and instability around the
western edge of the low will bring more showers and thunderstorms
this afternoon over the higher terrain of SW Idaho and Baker
County...with dry conditions expected for the remainder of the
area. The convection will diminish this evening with mostly clear
skies expected across all of southeast Oregon and SW Idaho late tonight
through Friday morning. The upper ridge will move into the region
on Friday...although residual moisture along with daytime heating
will promote a slight chance of afternoon showers and
thunderstorms over the northern high terrain. Temperatures will
trend warmer...with valley highs in the 80s on Friday.

Long term...Friday night through Thursday...upper level ridge
will build into the region for the weekend bringing warmer
conditions. Temperatures near 90f expected in the lowest valleys
Saturday and Sunday or 10-15 degrees above normal. A Pacific upper
level trough will arrive Sunday evening and a vigorous cold front
will move across the region early Monday morning. Showers and
thunderstorms will be possible with the frontal passage. Latest
models are slightly weaker with this system and farther
north...with less moisture to work with. Regardless temperatures
will fall to around 5 degrees below normal for Tuesday through
Thursday with enhanced chances of precipitation as the upper level
low slowly tracks across the Pacific northwest.


Boi watches/warnings/advisories...




previous short
previous long term....ka

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