Lake Wind Advisory 4, NWS Pocatello, ID

776 
WWUS75 KPIH 151957
NPWPIH

URGENT - WEATHER MESSAGE
National Weather Service Pocatello ID
157 PM MDT Thu Apr 15 2021

IDZ054-160100-
/O.CON.KPIH.LW.Y.0004.000000T0000Z-210416T0100Z/
Lower Snake River Plain-
Including the cities of Pocatello, Blackfoot, American Falls, 
Shelley, and Fort Hall
157 PM MDT Thu Apr 15 2021

...LAKE WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM MDT THIS
EVENING...

* WHAT...North winds 10 to 15 mph with gusts to 18 mph expected.

* WHERE...American Falls Reservoir.

* WHEN...Until 7 PM MDT this evening.

* IMPACTS...Strong northeast winds and rough waves will create 
  hazardous conditions for small craft on the reservoir.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Boaters on area lakes should use extra caution since strong winds
and rough waves can overturn small craft.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/pocatello

369 
WWUS75 KPIH 160110
NPWPIH

URGENT - WEATHER MESSAGE
National Weather Service Pocatello ID
710 PM MDT Thu Apr 15 2021

IDZ054-160215-
/O.EXP.KPIH.LW.Y.0004.000000T0000Z-210416T0100Z/
Lower Snake River Plain-
Including the cities of Pocatello, Blackfoot, American Falls, 
Shelley, and Fort Hall
710 PM MDT Thu Apr 15 2021

...LAKE WIND ADVISORY HAS EXPIRED...

Winds will continue to diminish and the lake wind advisory was
allowed to expire.

$$

For more information from the National Weather Service visit
https://weather.gov/pocatello

Area Forecast Discussion
National Weather Service Pocatello ID
220 PM MDT Wed Apr 14 2021

.SHORT TERM...Tonight through Friday night. Upper low centered
over northeast Nevada per satellite imagery this afternoon. Broad
swath of precipitation shifting north through Oregon and wrapping
around the low. Most of the precipitation falling as snow over
higher elevation areas. Working into the Snake Plain, surface
dewpoint depressions are rather steep, so it has had a difficult
time making it to the surface in many places, though there has
been just enough dynamics in other places to overcome steep
depressions. Most of the snowfall has accumulated in the southeast
corner, south of US26 and east of I-15. As upper low migrates
eastward overnight, expect the wrap-around precipitation to
continue, with most of the impact in the eastern highlands. Models
are still struggling to pin down precipitation and snowfall
amounts, and the latest runs have trended back down to the lower
ends of the probabilistic range again. That said, best
precipitation likely to occur through mid-day Thursday as upper
low grazes by to the south, and there is still quite a bit of
uncertainty on amounts. Low doesn't completely shift away until
late Friday, so ongoing light showers will remain possible
especially across the southeast. Upper trough weakens but remains
draped generally across Utah through the remainder of the short
term period, with upper ridge beginning to fold into East Idaho
from the north through Friday night. DMH

.LONG TERM...
Generally low-impact weather expected in the extended forecast
period. By Saturday morning, upper-low will be far enough east to
where the area should be precip-free for a few days as upper-level
ridging builds overhead. Temps will be seasonal Saturday before
increasing to above climatological norms Sunday and into the early
part of the work week. Expect daytime highs to reach into the 60s in
the lower elevations from Sunday into beyond. Only wrinkle in the
forecast is the uncertainty in the Mon/Tue timeframe where models
continue to show a shortwave potentially moving out of Canada.
Placement of this feature continues to vary from run-to-run in
global guidance. Ensembles show quite a temperature spread potential
so confidence in temps Mon/Tue is low. For now, will continue with
NBM forecast which also features low-end PoPs mainly across the
higher-terrain with this feature. Seems reasonable and until greater
certainty exists, there is no reason to deviate from it. McKaughan

&&

.AVIATION...
Upper-low over the region will bring prolonged low clouds, rain/snow
and wind to the area. So far today, precip has been rather
uneventful at terminals other than some brief light snow at KBYI.
For the rest of the afternoon and evening, hi-res guidance shows
areas of rain/snow showers impacting all terminals but they vary
with respect to timing and duration. This leads to a generally low-
confidence forecast. That being said, confidence is a bit higher
with the potential for some MVFR cigs during the overnight so those
have been included everywhere but KSUN. Localized reductions to
MVFR/IFR seem likely with any RA/SN but given the low confidence, do
not have any tempos for the time being and future amendments will be
likely based on radar trends over the next few hours. McKaughan

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 7 PM MDT this evening for IDZ054.

&&