751
FXUS65 KBYZ 081940
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
140 PM MDT Sat Jun 8 2024

.DISCUSSION...
Tonight through Sunday night...

The forecasted high temperatures for tomorrow have increased as
models seem to have backed off on the southward extend of the
upper low pressure system along the Canadian front range. Even the
GFS, though still favoring cooler solutions than other ensembles,
has come up and is now showing a median of around 70. Even though
there is still a lot of uncertainty in tomorrows temperatures,
the overall range of potential temperatures has been raised. Most
locations can now expect temperatures in the 70s tomorrow.

As we move toward late Sunday into Monday, a shortwave trough
will impact the region. Winds out of the east out ahead of the
wave will bring winds out of the south and east. This will advect
in high PWAT values late Sunday into Monday. Ensembles are
currently showing PWAT values of greater than 1 inch across the
region with values exceeding 1.25 inches for some. These values
are 150-200% of normal indicating abnormally moist conditions.
Models currently show precipitation falling late Sunday through
the overnight into Monday. There will be good shear throughout
with an upper jet producing 0-6km shear values in excess of 40kts
at times. Rosebud County and east will also get a good low level
jet Sunday night helping set up favorable hodographs. Due to most
of the convection being during the overnight hours, instability
will be hard to come by with warm low and mid levels that will
limit thunderstorm activity. Given the above factors, the Storm
Prediction Center currently has the region in a general
thunderstorm risk for this time period. Most of the precipitation
should exit into the Dakotas by 18Z Monday. Most of the region has
a 20-40% chance of getting 0.25 inches of precipitation with
inherent uncertainty due to the convective nature of the
precipitation.

Locations in the higher terrain will receive the most
precipitation with a 60-70% chance of getting 0.25 inches. With
snowpack above 8,500 ft receiving 0.25-0.5 inches of rainfall,
snowmelt will lead to concerns on area rivers and streams. Of
greatest concern is the Clarks Fork near Edgar and Belfry where
river levels are currently expected to approach flood stage early
Monday. People living in low lying areas should take steps to
protect property that may be impacted. Torgerson


Monday through Saturday...

Monday, after the wave passes through we will start to downslope
on the backside of the trough raising temperatures slightly from
Sunday. Tuesday through Thursday there is good ensemble agreement
that we will move into a zonal downsloping pattern. This will keep
things dry and bring the warmest temperatures of the year in the
mid to high 80s.

There is also good agreement that late in the week there will be
a Pacific trough to our west. There is no consensus yet on when
this trough will start heading our way. About 15% of clusters have
the trough moving into the region as early as Friday while others
keep it off the coast through Sunday. Friday looks dry as even
the cluster bringing in troughing shows hardly any precipitation.
Saturday looks mostly dry as well with about 40% of models showing
the trough making its way inland bringing around 0.10 inches of
precipitation to the region.

There is currently a hydrologic outlook in place due to the warm
temperatures this week. Snowmelt will be enhanced during this time
leading to high flows on area waterways. Flooding is not imminent
on large rivers and streams but smaller streams in the foothills
will be near bankfull over the next week. People near waterways
should take steps to protect property. Torgerson


&&

.AVIATION...

VFR conditions will prevail over the next 24 hours. Isolated
showers/thunderstorms are possible over the higher terrain after
21Z through late tonight, especially along the MT/WY border. Local
MVFR conditions can be expected near precipitation areas. Easterly
winds will be gusty(20-25kts) at times late this afternoon
through late this evening, mainly along the western foothills.
Chambers
&&

.PRELIMINARY POINT TEMP/POPS...

    Sun     Mon     Tue     Wed     Thu     Fri     Sat
-----------------------------------------------------------
BIL 053/073 055/078 054/085 058/086 055/082 056/085 059/082
    11/B    45/T    10/U    10/U    10/U    12/T    22/T
LVM 048/070 052/075 049/082 052/083 049/081 051/082 052/079
    13/T    66/T    11/U    11/U    11/U    12/T    33/T
HDN 053/075 057/078 052/086 055/086 053/084 056/086 057/083
    11/B    44/T    10/U    20/U    10/U    11/B    32/T
MLS 050/071 056/075 050/084 057/083 053/082 055/085 059/082
    11/B    44/T    10/U    20/U    10/U    11/U    32/W
4BQ 053/075 059/077 052/085 059/085 056/085 057/086 059/082
    11/B    23/T    10/U    20/U    10/U    11/B    32/T
BHK 046/069 053/073 048/081 054/083 051/081 051/082 054/080
    01/B    35/T    10/U    20/U    10/U    11/U    32/T
SHR 049/075 054/075 050/083 054/085 053/082 053/085 055/081
    22/T    34/T    20/U    10/U    10/U    12/T    32/T

&&

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

&&

$$
weather.gov/billings