261
FXUS65 KBYZ 101120
AFDBYZ

Area Forecast Discussion...Updated
National Weather Service Billings MT
520 AM MDT Thu Oct 10 2024

.KEY MESSAGES...

- 10 to 15 degrees cooler today.

- 15 to 30 percent chance of light showers tonight.

- Dry cold front Friday night brings closer to seasonal temps for
  the Weekend.

&&

.DISCUSSION...

Through Saturday night...

Weak dry cold front is currently moving through northwest zones,
and will push through the forecast area by about 9am this morning.
Main impacts with this front will be a shift to a northerly then
easterly wind through the day today, and temperatures about 10 to
15 degrees cooler than the record highs set yesterday (lower 70s).
Expect plenty of mid to high level cloud cover through the day.

Tonight a secondary push of northerly winds arrives thanks to a
subtle dip in the jet stream. An area of right rear quad jet
divergence combined with H7 frontogenesis and Pacific moisture
flowing through the region will bring 20 to 30 percent chance for
light rain showers to the northern half of the forecast area
(slightly further south than yesterdays forecast). Probabilities
for a tenth of an inch or more are less than 15%. Unfortunately
the cloud cover will make Aurora viewing difficult, but there does
look to be at least partial clearing after midnight.

Friday will be dry and a few degrees cooler than Thursday with
the secondary northerly wind push bringing more 60s into the
forecast. Expect some breezy easterly winds in the afternoon.

A quiet night in store Friday night. Yet another weak dry cold
front arrives overnight into Saturday morning with increased
cloud cover that may once again impact northern lights viewing.
Saturday looks dry with clearing skies and northerly winds. Highs
will be mainly in the 60s. Latest model runs have shifted the
blocking ridge advertised yesterday such that the northerly flow
on the east side of the block drags in slightly warmer air, so 60s
for SE Montana instead of the 50s advertised yesterday. Chambers

Sunday through Thursday...

Aforementioned blocking pattern to the west of the forecast area
will keep some cooler air over SE Montana, but again mainly in the
60s (25% chance for 50s Baker/Ekalaka). The rest of the area will
be back into the lower 70s Sunday afternoon with dry conditions
under sunny skies. Block breaks down Monday allowing ridge to
slide over central Montana. Rising heights and return of downslope
winds push temperatures back into the mid to upper 70s Monday
afternoon.

Ridging continues Tuesday and Wednesday for continued dry
conditions with temperatures in the mid to upper 70s. Monday
through Wednesday look like days of elevated grass fire concern.

A stronger cold front is being advertised now for Thursday with a
deep upper trof digging across the western U.S.. Temperatures
Thursday are now down in the 55 to 65 degree range, with
precipitation chances in the 30 to 40 percent range. Chambers
&&

.AVIATION...

12z TAF Updated Discussion...VFR conditions will prevail today.
Continued smoke advection from Idaho wildfires will bring reduced
slant range visibility at times.

Near KSHR visibility has dropped to under 3sm at times overnight
with westerly winds ahead of the front pushing smoke down the
front range. Expect periods of increased smoke concentration
through mid day but kept visibility around 5sm for this period as
winds will be swirling a bit with the fropa. Left a 3.5kft deck
in to cover higher elevation smoke. By mid day winds shifting to
the north-northeast should push smoke away from KSHR and the
Sheridan foothills through at least the evening hours. Chambers

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Fri     Sat     Sun     Mon     Tue     Wed
-------------------------------------------------------
BIL 070 045/069 047/069 040/070 042/077 044/079 046/078
    1/B 20/B    00/U    00/U    00/U    00/U    00/U
LVM 069 039/070 042/073 039/076 042/080 043/079 044/076
    1/H 20/B    00/U    00/U    00/U    00/U    01/U
HDN 072 043/073 044/071 037/072 038/078 041/079 041/080
    1/B 20/B    00/U    00/U    00/U    00/U    00/U
MLS 072 043/068 044/068 034/066 037/073 042/078 043/076
    0/B 30/B    00/U    00/U    00/U    00/U    00/U
4BQ 073 045/072 048/071 037/069 039/072 043/078 045/079
    0/H 10/B    00/B    00/U    00/U    00/U    00/U
BHK 073 039/065 042/067 030/062 032/066 036/073 039/076
    0/H 20/B    00/U    00/U    00/U    00/U    00/U
SHR 074 039/075 042/073 037/074 039/079 041/081 041/080
    0/K 10/B    00/B    00/U    00/U    00/U    00/U

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.

&&

$$
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