FXUS65 KBYZ 152106
Area Forecast Discussion
National Weather Service Billings MT
306 PM MDT Sat Jun 15 2019
.SHORT TERM...valid for Sun and Mon...
Upper-level northwesterly flow pattern looks to continue through
at least early next week. This pattern is often unstable for the
Northern Rockies with several weak disturbances moving
southeastward within the flow and producing periods of showers and
For this evening, the greatest chance of rain will be over the
mountains and adjacent foothills as the higher terrain helps to
initiate convective activity. The thunderstorms can then move off
the higher terrain over to the plains before diminishing due to
some warmer air aloft/capping. It appears that shower and
thunderstorm coverage should then be a bit greater on Sunday as a
larger-scale upper trough moves over the region.
The thunderstorms could produce gusty winds and small hail.
Atmospheric instability appears weak, so we are not expecting
severe thunderstorms. In addition, atmospheric moisture content
(precipitable water) is expected to be near or slightly above
climatological normal values, so there is appreciable moisture for
the showers and thunderstorms to work with, and heavy downpours
are possible. The projected storm motion should prevent flash
flooding from occurring.
High temperatures Sunday and Monday will generally be in the 70s
as low-level northeasterly flow supplies cool air to the region.
Low temperatures tonight through Monday night will generally range
from the middle 40s to the middle 50s. RMS
.LONG TERM...valid for Tue...Wed...Thu...Fri...Sat...
No major changes to the going pattern. Models continue to
advertise general northwest flow pattern over the northern Rockies
to start the week, evolving into more westerly flow but with
deepening upper low evolving over the northern plains. Neither of
these patterns is a particularly wet one for our area, but both
provide daily chances for showers and thunderstorms, particularly
for the mountains. Temperatures start off the week in the 70s to
low 80s, but cool into the 60s and lower 70s toward the end of the
week, as the upper lows cooling influence and cloud cover takes
Isolated to scattered showers and thunderstorms will develop late
afternoon over area mountains and drift eastward into the plains
through the evening hours. Latest models keep at least a slight
chance for widely scattered showers and thunderstorms continuing
through most of the night. Local MVFR conditions possible near
precipitation areas, otherwise VFR conditions will prevail.
.PRELIMINARY POINT TEMP/POPS...
Sun Mon Tue Wed Thu Fri Sat
BIL 054/074 054/077 055/081 056/080 052/071 049/069 049/072
23/T 22/T 24/T 42/T 22/T 33/T 22/T
LVM 048/072 049/074 050/077 050/077 045/068 042/065 043/069
36/T 36/T 33/T 31/U 22/T 23/T 33/T
HDN 054/074 053/075 054/079 054/079 051/070 048/068 048/071
22/T 13/T 24/T 52/T 33/T 23/T 22/T
MLS 053/075 051/076 052/078 054/078 050/070 047/068 047/071
12/T 01/U 13/T 42/T 22/T 22/T 22/T
4BQ 052/073 052/075 052/077 054/076 051/068 047/067 047/069
13/T 12/T 24/T 42/T 42/T 32/T 22/T
BHK 048/072 047/073 048/074 051/073 047/066 044/065 044/069
02/T 11/U 14/T 43/T 32/T 33/T 23/T
SHR 050/072 049/072 048/076 050/076 047/070 044/066 043/069
48/T 68/T 57/T 53/T 44/T 33/T 23/T
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