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Area forecast discussion
National Weather Service Pocatello Idaho
150 am MST Thu Nov 14 2019

Short term...through Friday night. A ridge of high pressure
remains on track to crest across southeast Idaho today, and this will
maintain dry and mild conditions. On Friday, the ridge will give
way to an incoming Pacific trough, and as a result cloud cover
will be on the increase through the day Friday, along with the
development of breezy conditions for the snake plain and mid/upper
slopes by afternoon. Ahead of the trough, high temperatures will
surge well into the 60s across the southern snake plain and
eastern Magic Valley -- within a couple of degrees of record highs
for the date. In terms of precipitation, this trough is not
particularly moisture-Maiden, but will still serve to bring some
of the first measurable precipitation thus far in November to
portions of southeast Idaho, mainly in higher elevation areas. The
precipitation will first arrive Friday evening across the central
Idaho mountains, then skipping over to the Continental
Divide/Island Park region around or just after midnight. Showers
will attempt to develop south across the higher terrain areas
between the snake plain and Wyoming border Friday night, but will
struggle to reach as far south as The Bear lake area. In all, this
system's precipitation will be relegated to mainly higher terrain
areas, and will fall mainly in the form of snow above the 6,000
foot elevation line. In terms of impacts, brief slick conditions
may be possible late Friday night from Island Park south to Pine
Creek Pass. Breezy conditions will linger Friday night, with 15-25
mph winds common across the snake plain, with isolated gusts to
45 mph possible across the typically windy areas such as the I-84
stretch from Burley south to sweetzer Summit. Ad

Long term...Saturday through next Thursday. The operational GFS and
European model (ecmwf) are in very good agreement early on in the period as a weak
Pacific trough shifts east through Montana early Saturday with the
persistent ridge of high pressure rebounding across the west
Saturday afternoon and continuing through Monday. By Monday night,
the operational GFS begins to look more like the outlier while the
GFS ensembles and European model (ecmwf) appear to split a closed low circulation off
the West Coast while the northern branch of the trough digs southeast into northern
Montana Tuesday and then amplifies Tuesday and Wednesday in response
to the ridge expanding across the NE Pacific. The preference here is
again the National blend of models which is supporting some mention
of precipitation across the central and eastern mountains near the Montana
and Wyoming Divide regions Monday night through Wednesday followed
by drier conditions Thursday as a broad ridge settles over the northwest.
There are no certainties here as the ensembles and operational
models are showing a great deal of variability. We should see a
return to near normal temperatures late in the period as colder
temperatures spill over The Divide in the split flow. Huston



&&

Aviation...a dry northwest flow aloft today will give way to
increasing high clouds from the west tonight. VFR conditions will
prevail through Friday morning. Huston



&&

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