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Area forecast discussion 
National Weather Service Billings Montana
213 am MDT sun Jul 24 2016

Short term...valid for tdy and Mon...

Latest radar imagery continues to show a few showers and
thunderstorms moving through the far S and southeast zones at 07z. The
models hold onto this precipitation until 18z when the responsible
shortwave pulls east-southeast away from the area. Thus have added low pops
to the affected areas through 18z. Kept some low pops in the
southern portion of the NE bighorns after 18z with some energy
continuing to affect this area. Temperatures will range from the
mid 80s to lower 90s today. Went a shade below the blended
guidance based on mixing seen on the WRF BUFKIT. While humidities
will be only in the teens and 20s, winds will be light, mitigating
fire weather concerns.

Weak upper ridging will be over the area tonight with a dry
airmass so had no need for pops. 850 mb temperatures in the mid
20s c will support mins in the 50s to lower 60s. Heights remain
high on Mon., But shortwave energy returns to the area, with low-
level S to southeast flow over the east. Resulting precipitable waters climb
to an inch or more over the NE part of the area. MUCAPES on the
sref increase to 500-1000 j/kg over the area Mon into Mon. Night.
The highest convective available potential energy shift east late Mon. Night. Bulk effective shear
was not overly the 30s. Models were in good agreement
in moving a cold front through the central zones by 12z Tuesday.
Based on the above, have spread slight chance to chance pops
across the area Mon. Afternoon, and continued these pops Mon.
Evening. Lingered slight chance pops ahead of the front over the
southeast zones late Mon. Night. Storm Prediction Center places the far east in a marginal risk
for severe storms Mon. Through Mon. Night where the highest convective available potential energy
and shear are forecast. Temperatures on Mon. Will be back in the
90s due to a warmer airmass and better mixing. Humidities will
continue to be low, but winds will be light. Arthur

Long term...valid for Tue...Wed...Thu...Fri...Sat...

A series of Pacific shortwaves will bring daily potential for
thunderstorms Tuesday through Thursday. Central Continental U.S. Ridge will
shift west and strengthen over the Great Basin by Thursday,
allowing for flow aloft to shift from zonal to northwesterly over
our region. Thus, Tuesday should be the warmest day followed by a
slight cooling trend Wednesday and Thursday. The cooler mid level
temps should allow for convection to develop a bit more
effectively, and some severe storms cannot ruled out in our east
where instability will be greatest. There could also be some
locally heavy rain in our east as the persistent easterly sfc flow
allows pwats to increase to around an inch if not a bit higher.
And of course, the anticipated increase in lightning activity
could result in additional fire starts.

Conditions should transition toward drier Friday as ridge begins
to build back in from the west. Warming trend will continue
Saturday, but monsoonal moisture may begin to wrap around Great
Basin ridge bringing a risk of higher-based thunderstorm activity
by next weekend.

As far as temps go, expect 90s Tuesday cooling to the mid or upper
80s by Thursday, then back to the 90s or perhaps near 100 degrees
next weekend. Models are in pretty good agreement with this
overall trend in temperatures as we move through the last week of



Isolated showers and thunderstorms over far southeast Montana will exit by 15z
this morning. Dry weather with VFR flight conditions will prevail
through tonight...along with light winds. Jkl


Preliminary point temp/pops...

Tdy Mon Tue Wed Thu Fri Sat
bil 088 061/095 063/095 064/091 062/087 060/088 062/094
1/u 02/T 22/T 22/T 23/T 32/T 21/u
lvm 086 051/093 053/095 054/090 054/087 050/089 052/094
0/u 03/T 22/T 22/T 23/T 32/T 22/T
hdn 090 058/097 061/096 061/093 059/089 056/089 059/095
1/u 02/T 22/T 22/T 23/T 32/T 21/u
mls 090 063/098 067/097 068/093 064/087 061/088 062/093
1/u 02/T 22/T 23/T 33/T 32/T 21/u
4bq 090 062/098 064/097 064/094 061/089 059/089 060/093
1/u 02/T 33/T 23/T 33/T 32/T 21/u
bhk 086 059/096 061/093 062/088 059/084 058/084 057/088
1/u 03/T 43/T 34/T 44/T 43/T 21/u
shr 088 055/096 057/096 057/093 057/088 054/090 054/094
1/b 12/T 22/T 22/T 24/T 42/T 22/T


Byz watches/warnings/advisories...



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