Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 210931

Area Forecast Discussion
National Weather Service Billings MT
331 AM MDT SAT MAY 21 2016

.SHORT TERM...valid for Tdy and Sun...

Upper low over Oregon will finally start to shift northeast today
tracking into southern Alberta by tomorrow morning. Height falls
will induce broad scale lift across our region with progs also
indicating decent frontogenesis pushing from west to east across
our CWA. Ahead of this system southeasterly surface winds will
increase over southeast Montana keeping dewpoints relatively high
for this time of year in the upper 40s to mid 50s across our
eastern zones. Combined with good heating ahead of the frontal
push this will mean good mucape across our eastern zones along
the line of 2000 j/kg. Shear profiles will increase as well by
evening in the east as surface front is pushed through. We have
been talking about this for a few days...and now the stage looks
set for potential super cell development in our east. I have also
added a mention of strong storms with small hail and strong winds
across areas west/northwest of Billings earlier in the afternoon
due to good lift and frontogenesis.

Once all this activity pushes through our region we will be under
a drier air mass on Sunday. However, the general flow will be
cyclonic and unstable due to a broad scale trough over the
western CONUS. So we will continue to mention some garden variety
thunderstorms (more like thundershowers) for Sunday. Temperatures
will be 5 to 15 degrees cooler Sunday over the area. BT

.LONG TERM...valid for Mon...Tue...Wed...Thu...Fri...

The weather next week continues to look unsettled. A chance of
showers and afternoon-evening thunderstorms exists each day as
numerous disturbances should move through the largely cyclonic
flow over the western U.S. There is some chance for more organized
rain from compact upper lows--one to our west and another to our
east--later in the week, as shown on the 00z ECMWF, but confidence
in this scenario is low given the long lead time and model

Temperatures should be near seasonal normals throughout the
period. RMS/BT


VFR should prevail today and tonight outside of
showers/thunderstorms. Low clouds are possible around KBIL and
KLVM this morning, mainly prior to 16z. Showers and thunderstorms
should move into the KLVM area around 18z-19z, near KBIL around
mid-afternoon, and near KSHR and KMLS late in the afternoon/early
evening. Conditions could drop to MVFR in thunderstorms. Storms
could be strong with large hail and high wind gusts. Mountains
will be obscured in showers and thunderstorms. RMS/BT



    Tdy Sun     Mon     Tue     Wed     Thu     Fri
BIL 076 046/067 044/068 044/068 047/068 047/069 048/070
    3/T 32/T    22/T    23/T    33/T    33/T    33/T
LVM 064 039/058 039/060 038/062 040/064 040/065 040/066
    6/T 23/T    34/T    44/T    43/T    33/T    33/T
HDN 082 045/071 042/070 044/070 048/070 048/071 050/072
    2/T 32/T    22/T    22/T    23/T    33/T    33/T
MLS 087 052/073 047/072 047/071 050/071 050/071 050/072
    2/T 52/T    22/T    22/T    33/T    33/T    33/T
4BQ 087 049/072 042/071 044/071 048/069 047/069 048/071
    3/T 53/T    22/T    22/T    33/T    33/T    33/T
BHK 078 049/073 042/070 045/070 047/069 047/068 048/069
    1/N 63/T    22/T    12/T    33/T    33/T    33/T
SHR 080 042/067 038/066 041/066 043/065 043/066 044/066
    2/T 22/T    13/T    32/T    33/T    33/T    33/T




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