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Area forecast discussion 
National Weather Service Billings Montana
819 PM MDT Wednesday may 27 2015


No update to inherited forecast this evening. Everything
appears generally on track...with continuation of isolated to
scattered showers and thunderstorms across the region. Aag


Short term...valid for Thursday and Friday...

Upper low continues to move slowly over northern Idaho. Shortwave in
eastern Montana has allowed for a line of convection to develop in
Fallon and Carter counties this afternoon. Weak jet streak lifting out
of the SW has produced scattered thunderstorm activity in central parts
including at Billings at 2pm. Further west...we are seeing
activity in south central Montana and southeast Idaho moving toward our
western areas. Fairly complex picture but the overall theme of the
forecast is periods of showers and thunderstorms across our region
into Friday. Best potential is Thursday afternoon into early
Friday as upper low to our west finally moves across our County Warning Area.
Upslope areas of our south will see enhanced precipitation as flow turns
northerly tomorrow. Could see a half inch to inch of precipitation in
Sheridan County which will keep flows up on the goose creeks as
well as The Tongue/powder rivers and their tributaries. Do not see
enough precipitation for an additional flood risk but still need to be
aware in these areas.

Canadian surface ridge will push into the northern plains and bring a
shift to NE-east winds and drying/stabilizing on Friday. Latest model
runs show this occurring a bit faster as upper trough exits to our have adjusted probability of precipitation down a little sooner and removed
ts across all but our SW parts on Friday. Cannot rule out some
light shower activity across our west Friday night per weak Pacific
energy...but should not be much as heights rise to the middle 570s
with flat ridging over the region.

Expect highs from the middle 60s to middle 70s again tomorrow...then
mostly 60s on Friday as we draw in cooler Canadian air.


Long term...valid for Sat...sun...Mon...Tue...Wed...

Active weather pattern to continue into the extended period. Next
upper trough of interest will begin to push onto the West Coast
this weekend. As it does...any ridging over our region ahead of
this system looks weak with Overall Flat flow. This will allow
pieces of energy to work across the region. Enough late may
instability and moisture to work with for a continued risk of
daily showers/storms. Nothing organized at this
activity should remain widely scattered in nature. Airmass does temperatures look to begin a climb into the 80s this
weekend which will last into Monday.

More organized convection and potentially severe conditions setting
up for early next week that will need to be monitored as main
energy/upper low moves across the northern rockies. Monday and
potentially into Tuesday...models advertise good instability/shear
and upper level jet support. If these conditions look same in
coming days...will need to begin advertising as potentially our
first organized severe thunderstorm event of the season. Cyclonic
flow continues behind the system for Wednesday for continued
unsettled conditions. Temperatures by the middle of next week will
cool considerably behind the system. Frieders



Scattered showers and isolated thunderstorms will continue across
the forecast area this evening...with just an isolated shower
possible after 06z. VFR conditions will prevail with localized
MVFR conditions within the heavier rain showers this evening. The
mountains will be obscured at times. Hooley


Preliminary point temp/pops...

Thursday Friday Sat sun Monday Tuesday Wednesday
bil 050/070 048/066 048/078 053/082 055/082 053/076 051/066
46/T 63/west 22/T 22/T 24/T 44/T 43/T
lvm 044/064 045/065 047/074 049/076 049/075 047/071 045/064
56/T 64/T 23/T 33/T 35/T 54/T 44/T
hdn 049/073 048/068 046/080 052/084 055/086 053/078 051/069
35/T 64/west 22/T 22/T 24/T 44/T 43/T
mls 052/075 048/066 047/077 053/081 057/084 056/076 053/068
33/T 42/west 12/T 33/T 24/T 44/T 44/T
4bq 050/072 050/065 046/074 053/080 057/084 056/076 053/070
35/T 54/west 12/T 22/T 24/T 45/T 53/T
bhk 049/073 045/063 041/068 047/077 053/082 053/074 050/068
53/T 42/west 02/T 33/T 24/T 44/T 44/T
shr 046/069 046/062 044/074 049/078 051/081 050/075 049/067
36/T 76/west 22/T 22/T 24/T 44/T 43/T


Byz watches/warnings/advisories...



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