Area Forecast Discussion
Issued by NWS Billings, MT
FXUS65 KBYZ 191553
Area Forecast Discussion...Updated
National Weather Service Billings MT
953 AM MDT FRI AUG 19 2016
Update to accelerate drying trend across the area. Not willing to
zero out pops because diurnal warming should combine with cold air
aloft to allow additional shower and isolated thunder to develop.
.SHORT TERM...valid for Tdy and Sat...
Strong shortwave trough dropping into south central Montana early
this morning was generating widespread showers across southern and
eastern Montana. This trough will push into the Dakotas early this
afternoon. So, rain will taper off over south central zones this
morning and linger into the afternoon in the east. Lightning has
been limited, but enough instability for a few strikes over the
eastern half of the area. A secondary shortwave is progged to drop
into southern Montana in developing northerly flow for a lingering
chance of convection this afternoon for all locations. Freezing
levels were dropping quickly and there will be some light
accumulation of snow above 9 thousand feet early this morning.
This focus will shift more to the Bighorns early today. Forecast
highs today will be tricky, especially over western and central
zones which will have the potential for some cloud breaks in the
afternoon. Guidance was indicating such and has bumped highs a
couple of degrees. Will keep forecast highs unchanged but could be
a couple degrees warmer with a little sunshine.
Clouds will clear out tonight and set the stage for a chilly
overnight. Temperatures will fall into the 40`s, with lows around
40 nearest the foothills. Saturday will be a dry and warmer day.
Have kept the idea of cutting guidance a little bit with recent
rainfall, but may need to bump highs a bit more if current model
trends of decent low level downslope flow during the afternoon
.LONG TERM...valid for Sun...Mon...Tue...Wed...Thu...
Little in the way of changes for the extended forecast
period...as models have changed little. The one change that is
noticeable is the upper level low tracking across Canada through
the latter portion of the period appears to be a little further
south...pointing to possibility of cooler temps and more precip if
Ridging dominates the pattern to start the extended period...with
a warming trend through Monday. Temps climb to 90 degree mark in
many areas once again...as westerly downslope winds help push
temps upward. A cold front associated with the upper level low
moving across Canada pushes through the region Tuesday. Models
still want to keep this system dry...so have kept inherited pops
at this time.
The upper low slides across southern Canada through the remainder
of the period...keeping northwest winds in place over the region.
This should keep temps below normal through the remainder of the
period. Although multiple waves slide through the flow...moisture
still appears to be quite limited...so have kept slight pops in
place at this time. AAG
An area of showers will continue into the afternoon across
southeastern Montana, mainly south and east of KSHR to KMLS. These
could produce MVFR conditions. Otherwise expect VFR across the
rest of the area. Reimer
.PRELIMINARY POINT TEMP/POPS...
Tdy Sat Sun Mon Tue Wed Thu
BIL 065 047/077 051/088 059/091 056/081 054/075 052/073
2/T 10/U 01/U 11/U 11/B 11/B 12/T
LVM 066 040/078 047/090 051/089 047/080 045/076 045/075
2/W 10/U 01/U 11/U 11/U 11/B 12/T
HDN 065 045/079 050/090 057/093 055/083 052/078 052/076
7/T 10/U 01/U 11/U 11/B 11/B 12/T
MLS 067 047/077 051/089 058/093 058/082 054/077 052/074
6/T 10/U 01/U 11/U 22/T 11/B 12/T
4BQ 063 044/074 048/086 058/093 058/083 054/076 050/074
8/T 20/B 01/U 11/U 11/B 11/B 12/T
BHK 065 045/073 048/084 054/093 055/081 050/074 049/071
9/T 10/B 01/U 10/U 11/B 11/B 12/T
SHR 060 040/075 046/087 054/091 053/081 050/076 048/073
7/T 20/U 01/U 11/U 11/U 11/B 12/T