National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

579
FXUS65 KBYZ 160946
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
346 AM MDT Wed Aug 16 2017

... Fire Weather Watch Thursday Afternoon and Evening ...


.SHORT TERM...valid for Tdy and Thu...

Quiet weather pattern across the area tonight with generally
clear skies and light winds across most of the CWA. A little bit
of fog could creep into Baker from the east with dewpoint
depressions only a few degrees at this hour and light southerly
winds over easternmost MT.

This afternoon, ridging is shunted eastward into the Dakotas as a
weak upper level vort max moves into the Absarokas. A couple
showers and thunderstorms possible over the Absarokas this
afternoon but elsewhere expecting clear skies with temperatures
5-10 degrees warmer than yesterday.

Stronger low pressure system moves intro the area Thursday
morning. Atmospheric column looks quite dry with humidity values
in the teens across all of the central and eastern zones.
Soundings show mixing up to 600 MB with temperatures in the upper
80s to near 90. NW winds 15 to 30 mph should be able to mix down
to the surface for several hours during the afternoon and early
evening. Combination of winds and low humidly values has led to
us issuing a Fire Weather Watch Thursday afternoon and evening for
most of our central and eastern Montana fire weather zones.

As surface front pushes eastward late Thursday afternoon, there
should be enough moisture over the far eastern Plains for isolated
thunderstorms to develop. Walsh

.LONG TERM...valid for Fri...Sat...Sun...Mon...Tue...

Upper ridging should dominate our weather on Friday with sunny
skies and warm temperatures. Flow then flattens /turns westerly/
on Saturday with a weak cool front moving across the eastern half
of Montana. This front can drop temperatures by just a few degrees
from Friday`s expected highs. Pressure rises behind the front can
bring some breezy conditions mainly to eastern Montana for
Saturday afternoon. Minimum relative humidity values should be in
the upper teens so could have some fire weather concerns Saturday
afternoon in SE MT.

Upper westerly flow continues on Sunday and Monday with perhaps a
slight turn southwesterly to allow for some mid-level monsoonal
moisture to get to our region. This pattern would tend to favor
increased cloudiness /though not overcast skies/ over the region
and showers and thunderstorms mainly in the mountains. On Monday,
models diverge a bit with ECMWF showing a weak wave crossing the
region, which could produce a few isolated showers and
thunderstorms across the CWA, and the GFS showing upper ridging
and dry conditions dominating. The EC has not had run-to-run
consistency for Monday so am not including a chance of
showers/storms in the lower elevations yet. Models then agree on
upper ridging and dry weather for Tuesday.

High temperatures will generally be in the 80s across the CWA with
lower 90s possible in southeast MT Friday and Saturday. RMS
&&

.AVIATION...

VFR will prevail today. RMS

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Thu     Fri     Sat     Sun     Mon     Tue
-------------------------------------------------------
BIL 086 059/086 056/090 059/088 058/084 057/084 057/087
    0/U 10/U    00/U    00/U    11/U    11/B    11/U
LVM 083 051/084 047/089 050/088 049/085 049/085 049/087
    1/U 00/U    00/U    00/U    11/U    11/U    11/U
HDN 088 058/088 054/092 056/090 057/087 055/086 056/089
    0/U 00/B    00/U    00/U    11/U    11/B    11/U
MLS 087 061/090 056/091 060/091 059/087 057/085 057/088
    0/U 00/B    00/U    00/U    12/T    21/B    11/U
4BQ 084 056/089 054/089 058/091 058/088 057/086 056/088
    0/U 01/B    10/U    00/U    12/T    21/B    11/U
BHK 082 057/089 052/087 057/090 056/084 054/082 054/085
    0/U 01/B    10/U    00/U    12/T    21/B    11/U
SHR 081 057/084 050/087 053/088 053/085 052/084 052/086
    1/U 11/B    10/U    00/U    11/U    11/B    11/U

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...Red Flag Warning in effect from noon today to 9 PM MDT this
      evening FOR ZONE 117.
     Fire Weather Watch in effect from Thursday afternoon through
      Thursday evening FOR ZONES 127>133.
WY...None.

&&

$$
weather.gov/billings