840 
FXUS65 KBOI 142031
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
231 PM MDT Sat Sep 14 2019

.SHORT TERM...Tonight through Tuesday...Southwest flow aloft will
back strongly as a strong and large upper level low sharpens and 
drops southeast toward the PacNW coast. This will give us a hot 
Sunday as warm air is advected northeast into the region. A cold 
front will strengthen as it moves through the area Monday. As the 
upper low approaches, showers will move in from the west and 
spread from eastern Oregon into southwest Idaho during the day 
Monday. Most of these showers will develop behind the front. 
Monday's highs will be significantly lower than Sunday, with 
readings dropping 10 to 20 degrees. The largest temperature 
changes will be in eastern Oregon where the front will move 
through in the morning. Monday night, as the upper level trough 
finally moves through, showers will continue over much of the 
area. Temps will fall to below normal Tuesday morning. Tuesday 
afternoon, showers will still be possible mainly in the north and 
east. High temps Tue will be 5 to 10 degrees below normal.

.LONG TERM...Tuesday night through Saturday...Clouds will be 
increasing on Tuesday night ahead of another deep upper level 
trough that will move through the intermountain west late 
Wednesday through Friday. This feature will keep temperatures 
10-15 degrees below normal and bring a good chance of showers to 
the area. The probability of precipitation increases across the 
area beginning on Wednesday and becomes more likely on Wednesday 
night and Thursday. There are some model differences Thursday 
through Friday, with the ECMWF being a little faster with the 
progression of the trough than the GFS and Canadian models. Snow 
levels will be as low as 8000 feet on Thursday bringing a dusting 
of snow to the high mountain peaks. All models show the trough 
moving east of the area by Friday afternoon with chances of 
precipitation diminishing and temperatures warming afterwards.

&&

.AVIATION...VFR. Mostly clear skies with a few high cirrus 
clouds. Expect light and variable surface winds less than 10 kts 
tonight. On Sunday...VFR will continue with mostly clear skies. 
Southwesterly surface winds will increase to 15 to 20 kts across 
most of southeastern Oregon in the afternoon. Surface winds across
southwestern Idaho will be from the south or southeast at 10 to 
15 kts. Expect southwest winds aloft at 10 K feet MSL of 20 kts 
increasing to 30 kts on Sunday afternoon.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.
OR...None.

&&

$$

www.weather.gov/Boise
www.facebook.com/NWSBoise
www.twitter.com/NWSBoise

SHORT TERM...SP
LONG TERM....JB/JB
AVIATION.....JB