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 31 32 33 34 35 36 37
000
FXUS65 KPIH 210858
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
258 AM MDT Sun May 21 2017

.SHORT TERM...Tonight through Tuesday night. Compact disturbance
is currently centered over southern ID, with favorable zone of
lift in place, particularly along and south of the I-84/86
corridor. This disturbance has been especially effective at
utilizing available moisture, thus precipitation rates and
subsequent amounts have over-achieved a bit. Areas around Burley
are approaching 0.25" of rain in the last 3 hours. Given
observational and high-resolution model guidance, have raised
precipitation chances and amounts today for areas mainly
along/south of I-84/86 where clouds and precipitation will be most
persistent today. Some locations may see up to an additional
0.20" of rain today, with the most likely locations in the high
terrain areas of Cassia and Oneida counties. Enough instability is
forecast this afternoon/early evening for these areas for isolated
thunderstorms. Precipitation associated with this system will
taper off this evening. A second wave will race southward out of
Alberta on Monday and track southward across Wyoming. This wave
will be just close enough to trigger an isolated shower or
thunderstorm along the WY border Monday afternoon and evening. Dry
weather is expected for Tuesday. Temperatures are expected to
rise to about 10 degrees above climatological averages by Tuesday.

Winds today behind the wave of low pressure are expected to
become N-NE across the Snake Plain at 10-15 mph by mid-late
Afternoon through early Evening, just near the threshold for a
Lake Wind Advisory for American Falls Reservoir. Due to winds
being borderline in terms of speed and duration, have opted
against an Advisory at this time. However, do expect some chop on
area waterways today. AD/Valle

.LONG TERM...Wednesday through Sunday. GFS and European continue
the trends of showing good model to model consistency, but not run
to run consistency, which continues to produce a good deal of
uncertainty in the forecast. Trend definitely looks like some sort
of trough/low pressure feature over the Pacific Northwest, but
lots of questions in the details. This morning`s runs show the low
that was over us, now over central Canada, thus the hesitation to
really buy off on any solution for now. With that said, did
increase precipitation chances as we are seeing some sort of
unsettled weather over the region for late week along with cooler
temps.

Valle


&&

.AVIATION...Watching showers from Saturday night`s thunderstorms
slowly drift south. Could see a few showers affect the TAF sites
around PIH and BYI this morning. Otherwise, today should be
relatively quiet for TAF sites with ceilings remaining vfr and winds
light.

Valle


&&

.HYDROLOGY...A transitory high pressure ridge expected Monday
through Tuesday night will help warm temperatures into the 65-75F
range in the mountains and 70 to 80F range in the lower valleys
by Wednesday. By Wednesday afternoon through Friday there will be
a chance of afternoon showers and possible thunderstorms. Snow
melt in the mountains is expected to increase pace again the later
part of the week. RS


&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$


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