Area Forecast Discussion
Issued by NWS Pocatello, ID

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
FXUS65 KPIH 282014

Area Forecast Discussion
National Weather Service Pocatello ID
214 PM MDT Tue Mar 28 2017

.SHORT TERM...Tonight through Friday. We should be dry overnight
across eastern Idaho. We`ll be on the lookout for the potential
development of patchy fog or stratus, although high and mid level
clouds should be on the increase which would mitigate that issue.
We are expecting enough moisture tomorrow for an increase in
showers across the central mountains and along the divide WEST of
Monida Pass. The rest of the area will continue to see an
increase in clouds from the northwest. We are expecting it to warm
up quite a bit over the next 24 hours, with 50s and 60s in the
valleys and 40s in the high country.

At this point, the storm moving into the West should arrive a bit
quicker for tomorrow night. We are expecting rain and snow over
most of eastern Idaho by early Thursday morning. Beyond that,
where we see precipitation (especially where we will see heavier
bands/pockets) is still up in the air. The models are still
struggling with the split flow moving into the Rockies. The NAM
looked quite a bit different than the GFS and ECMWF, so we decided
to not include any bit and pieces from that beyond Thursday
morning. We didn`t make any big swings based on the lack of
confidence, and kept with a broadbrush approach of rain and
mountain snow through Thursday night. We should see things
tapering off and cooling down on Friday, but again it all depends
on how much splitting takes place and where we end up across
eastern Idaho. We do have high snow levels until Thursday
night/Friday, generally between 7000-8500ft with most of the
decent snow falling above 7000-7500ft. Will we need any winter
headlines for the central mountains. As of right now, the answer
is no. We are looking at 3-8" pretty high up and it will be
breezy. It`s not enough at this point to put something out there.
Rain and snowmelt numbers are pretty high, 0.4-1.25" depending on
location. Those numbers will change as we get closer and into this
event, once we get a better idea on where things set up. Winds
become an issue Thursday afternoon and Friday. We should see winds
25-30mph with higher gusts as the front comes through from the
west, with winds becoming northerly on Friday. It looks pretty
gusty across a good chunk of the Snake Plain and also along the
Divide and south-central highlands.  Keyes

.LONG TERM...Fri night through next Tue night. The GFS has given up
on its very dry solution, and now looks more like the ECMWF. Another
moderate strength storm is expected to arrive as early as Sat night
but more likely Sun. With not much recovery in between, snow levels
will stay low, reaching the floor of the Snake River plain Sun
night, if any precipitation is left. The northwest air flow behind
this will stay moist enough for a chance of snow and afternoon rain
for Mon and Tue in the central Idaho mountains and the northern and
eastern highlands that border MT and WY. Winds are not breezy to
windy until after the front passes Sun, then it stays breezy to
windy through Mon afternoon. Messick


.AVIATION...High pressure will slowly give way to a round of
clouds and moisture during the day Wed. Until then, the only fly
in the ointment is radiation fog and stratus for late tonight at
KIDA and KDIJ. Would have expected more Tue morning at KIDA, then
diminishing threat tomorrow, but there was nothing Tue morning, so
do not think stratus will be a problem, though have put in
"SCT004" as a hint of stratus development. At KDIJ it seems more
likely, as the airdrome has struggled today getting to marginal
VFR. So have a shorter duration for KDIJ tomorrow as conditions
trend drier. Messick


.HYDROLOGY...In coordination with County Emergency Managers, the
Flood Watch continues, although Minidoka and portions of Lincoln
Counties have been eliminated as much of the snow pack has gradually
melted away this week. The watch was extended a half day beyond the
next big rain event on Thu/Thu night. The Portneuf near Pocatello is
now expected to fluctuate at least through 06 April in the 1-foot
range for Minor Flood Stage. The Bear River at the ID-WY border is
now expected to fall below flood stage Wed morning shortly after
0700 MDT. All four Flood Advisories are continuing through Fri mid-
day and have not been altered.  Messick


Flood Watch through Friday afternoon for IDZ017>019-022>025-031-


$$ is the U.S. government's official web portal to all federal, state and local government web resources and services.