Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 232057

Area Forecast Discussion
National Weather Service Billings MT
257 PM MDT Sun Oct 23 2016

.SHORT TERM...valid for Mon and Tue...

An upper ridge over the southern and central Rockies was slowly
building northward. This has provided another dry day for southern
Montana and northern Wyoming. A stream of moisture was working
northeast into the area from the southwest. Moisture was limited
and energy embedded in the flow was weak, so will keep PoPs out
tonight. Southwest flow will remain in place Monday through
Tuesday. Disorganized energy streams across the area through the
period. Will keep low PoPs over the higher terrain with the influx
of weak energy. A stronger wave breaks off of an upper low off the
Pacific northwest and runs across western and northern Montana on
its way into southern Canada. The tail end of this wave brushes
our western and northern zones Tuesday night, so included low PoPs
for it. Temperatures will remain mild with mid level downslope
flow. TWH

.LONG TERM...valid for Wed...Thu...Fri...Sat...Sun...

Models were in a little better agreement for the end of the week
but still problematic with timing of the next wave to impact the
area. An upper ridge will be suppressed a little bit by energy
riding over the top Tuesday night into Wednesday. The ridge builds
back up a bit Thursday, but the ECMWF was much more aggressive in
this regard. The GFS sends a northern wave across Montana Thursday
afternoon and night, and flattens the ridge quite a bit sending a
weak cold front through the area for Friday. The ECMWF keeps the
ridge strong and deflects weakening energy into Canada and then
sends a stronger wave across Friday night into Saturday. The GFS
has this secondary system too but was earlier with it sending it
across Friday into Friday night. Due to model inconsistencies, did
not make a lot of changes to the grids for the extended. Did
modify the pops a bit for the end of the week to get more of a
blend picture in there to take into account the ECMWF scenario.
The week looks mild with high temperatures in the 60s. TWH



Most of the area can expect mainly VFR conditions through the
evening and overnight with just some passing high clouds as high
pressure dominates over the Northern Rockies. Some patchy fog is
possible for far eastern areas overnight. STP



    Mon     Tue     Wed     Thu     Fri     Sat     Sun
BIL 041/067 046/068 044/066 045/068 046/065 042/061 042/064
    01/B    11/B    10/B    00/B    12/W    21/B    11/B
LVM 039/066 045/065 042/065 044/069 044/063 041/060 041/062
    01/N    12/W    21/B    10/B    12/W    22/W    12/W
HDN 038/069 043/070 042/067 042/069 042/066 041/063 040/066
    00/B    11/B    10/B    00/B    12/W    21/B    11/B
MLS 038/063 040/065 044/064 042/066 044/061 040/059 040/063
    00/B    11/B    20/B    00/B    01/B    21/B    11/U
4BQ 037/068 041/069 043/066 041/070 044/066 039/062 040/065
    00/B    01/B    10/B    00/B    02/W    21/B    11/B
BHK 034/057 036/060 040/062 037/064 041/060 036/055 036/060
    00/B    01/B    20/B    00/B    01/B    21/B    11/U
SHR 037/069 042/068 039/065 039/071 040/066 037/063 038/065
    00/B    11/B    10/B    00/B    12/W    21/B    11/B




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