Area Forecast Discussion
Issued by NWS Pocatello, ID

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FXUS65 KPIH 262032

Area Forecast Discussion
National Weather Service Pocatello ID
232 PM MDT Wed Apr 26 2017

.SHORT TERM...Rain showers spreading in from the west this
afternoon in current radar imagery. Airmass is unstable enough
despite cloud cover for isolated thunderstorms to develop this
afternoon and evening in the Upper snake Highlands and the South
central Highlands over to Bear Lake. Lighting strikes have been
detected southeast of Kilgore. A surface cold front is expected to
cross into the Upper snake Plain around midnight tonight. Behind
the front, a strong surface pressure gradient and respectable cold
air advection will boost winds to advisory levels in the Eastern
Magic Valley, Lower Snake Plain and the South Central Highlands. A
wind advisory has been issued for midnight tonight through 8 pm
MDT Thursday. Models have been consistent with some energy of this
disturbance digging south into Nevada and Utah, taking a portion
of the precipitation with it. That`s good in the sense that less
rain will mean less risk of pushing local rivers to higher flood
levels. Overnight snow levels will be around 4500 feet elevation
Thursday morning. Rain changing to snow with 1 to 3 inches
possible on roads leading through pass areas. Temperatures war
during the day into the lower to middle 40s with snow turning to
slush. Some heavier snow accumulation is possible above 7000 feet
elevation. thursday and Friday, northwesterly flow aloft will keep
colder air over this area and a chance of showers in the forecast
both days. By Saturday, high pressure slip into Southern Idaho and
limit most shower to the Upper Snake Highlands and Eastern
Highlands. A little warm up expected by Saturday. RS

.LONG TERM...Saturday night through Wednesday night. The models are
still trending drier especially by the middle of next week. We are
still looking for off and on showers especially across higher
terrain as a few systems drop southeast toward the Plains. High
pressure eventually shifts far enough east to cut any chance of
showers off for us. That will likely start a trend of pretty chilly
nights and mild afternoons. Might have to deal with some frost/freeze
headlines as the official growing season starts on the 1st.  Keyes


.AVIATION...We are seeing showers (and the potential thunderstorms)
increasing as expected this afternoon. You can expect MVFR/IFR
weather from low ceilings and/or visibility through this evening. We
could see some small hail/graupel also from stronger cells that
develop IF we can get instability going. Overnight we dry out over
much of eastern Idaho, although showers are possible in the eastern
highlands affecting KDIJ. We will need to watch for a convergence
band that sets up between KPIH and KIDA overnight, which will keep
showers and MVFR/IFR conditions going. This will most likely affect
KIDA as most indications are it won`t drop much farther south. As we
dry out, we will see winds actually pick up overnight and continue
into Thursday morning. The strongest winds will be for KBYI and
KPIH, where sustained winds peak around 30kts with gusts to 45kts.
Showers will persist/regenerate over the mountains tomorrow. The
convergence band may never really go away and should eventually
shift south toward KPIH late in the afternoon. It will remain windy
with a gradual decrease in the afternoon. Keyes


Wind Advisory from midnight tonight to 8 PM MDT Thursday for


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