EF0 tornado, Snowline to (Mqm)Monida, Montana, August 6, 2023

Area Forecast Discussion
National Weather Service Great Falls MT
202 PM MDT Sun Aug 6 2023

.SYNOPSIS...

Cool and damp conditions will slowly dissipate across North
Central Montana as a weather system slowly moves eastward out of
the area. Southwestern Montana has seen a bit of a different day
today, as departing clouds have allowed for some sunshine to make
an appearance. Expect a drier, but still cloudy and somewhat cool
day across the area on Monday, though a few showers and
thunderstorms will remain possible.

&&

.DISCUSSION...

A slow moving upper level low continues to linger over the area
today, resulting in a fairly widespread area of light to moderate
rainfall across North Central Montana this afternoon. For the
most part, this rainfall is fairly beneficial and slightly unusual
for this time of year, when most of our rainfall comes from
afternoon and evening thunderstorms, but the mostly gentle nature
of the rainfall is allowing it to soak into the ground quite
nicely. While we have been concerned about the possibility for
heavier thunderstorms to result in some flooding concerns, the
widespread rainfall and cloud cover has kept temperatures largely
in the 60s across the area, which has really put a chill on the
potential for convection and the associated heavier rainfall.
While a few isolated areas of heavier rainfall have developed as
of early this afternoon, they seem to be moving along fast enough
to prevent any sort of flooding at this time.

This system will finally exit to the east this evening, which will
allow skies to gradually clear up a bit overnight tonight.
However, our next weather system will attempt to push into the
area Monday and Monday night. Ahead of this system, Monday still
looks somewhat cloudy and cool for this time of year, with highs
across Southwestern Montana topping out in the low to mid 70s,
with highs near 80 across the Plains. Showers and thunderstorms
will try to move through Southwestern Montana Monday night as the
upper level system moves through, though the current timing of
this system will likely make it difficult for showers and storms
to reach their full potential. Upper level ridging will build in
on Tuesday, which should help kick the showers and storms out of
the area by the late afternoon.

The next disturbance will move through on Wednesday and Wednesday
evening, which will mainly manifest itself with some gusty winds
across the plains as it attempts to sweep out some of the
lingering moisture across the area, though a few showers and
storms may get going across the southwestern mountains. After this
system, the upper level flow will be mostly zonal for the second
half of the week, with temperatures gradually warming up with
drier conditions for the second half of the week. Ludwig

&&

.AVIATION...
1150 AM MDT Sun Aug 6 2023 (06/18Z TAF Period)

VFR conditions will prevail across SW MT, including KWYS, KEKS,
KBZN, and KHLN as drier air works into the area. A few isolated SHRA
and even a TSRA will develop this afternoon, but impacts to any
terminals should be brief. Further north, widespread light to
moderate rainfall will continue to affect KLWT, KGTF, and even KCTB
through this afternoon, bringing MVFR to, at times, IFR conditions
due to low clouds and reduced visibility. Skies should clear across
all areas overnight, though there will be the potential for some fog
to develop overnight tonight. Ludwig

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.

&&

.HYDROLOGY...

Isolated heavy thunderstorms embedded within a broader area of
light rain will be possible through this afternoon as a slow
moving upper level low remains above the area. While flooding is
generally not a major concern, we will have to watch for some
areas of minor street flooding should the heavier rain moves over
an urbanized area, and burn scars will need to be monitored for
increased runoff. Drier conditions are expected on Monday, though
an isolated heavier thunderstorm remains possible. Ludwig

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  51  79  53  81 /  50  30  10  20
CTB  48  82  51  82 /  10  20  10  10
HLN  55  80  57  81 /  60  50  40  30
BZN  50  75  51  75 /  60  50  40  40
WYS  39  65  42  63 /  60  70  60  60
DLN  46  71  48  68 /  40  60  50  30
HVR  53  86  54  88 /  10  20  10  10
LWT  49  74  49  78 /  80  40  10  30

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&

http://www.weather.gov/greatfalls