Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Billings Montana
331 am MDT Sat Aug 1 2015

Short term...valid for today and sun...

This will be a hot and dry weekend. Dry northwest flow will
provide abundant sunshine and allow mixing to generate highs in
the middle to upper 90s. Billings will be around 3 degrees from
record highs both today and Sunday. Humidity levels will be very
dry with many locations falling to around 10 percent in the
afternoon. A weak surface trough will slide across northern
Montana today and provide some northwest breezes. Monsoon moisture
will be suppressed to the south. Some cumulus development will
occur over the mountains...especially on monsoon
moisture creeps north. The will be the only chance and location
for convection this weekend. Twh

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

Only minor changes to the extended models remain in
good agreement throughout the bulk of the period. Great
improvement in model agreement has been made in movement of
Pacific trough across southern Canada through the period.

Persistent upper level ridge remains in control over the region
for much of the day Monday. A disturbance...with associated
monsoonal moisture pushed into the west Monday evening forcing a
slight amplification before flattening the ridge. This is a slower
transitions than previous runs. This should lead to slightly
higher temperatures for Monday...with greater impacts from
ridging...potential compressional heating...and lesser cloud cover
than previously indicated. From this point on several waves...with
associated monsoonal moisture...radiate off the Pacific low that
slowly pushes east...bringing afternoon and evening shower and
thunderstorm potential each day. From this point models
diverge...mainly differing on how quickly the ridge redevelops.
The strongest wave cross thing the region appears to be Wednesday
evening into Thursday. Did raise probability of precipitation a bit with this
models are in such good agreement. This wave Marks the end of
southwest flow across the region...introducing zonal flow as upper
low crosses to the north. Although zonal flow and some potential
for downslope flow air into the region behind the
trough...should bring coolest day of the period Friday...but still
with low to middle 80s. Have also kept slight probability of precipitation in place at this
time...with possible influence of cyclonic flow over the region.
Models diverge a bit at this point...differing on how quickly to
build in the upper level ridge behind the passing low. Aag



VFR conditions expected across the area today. Breezy conditions
can be expected for all routes this afternoon...through about
sunset...with highest gusts around 20 knots. Aag


Preliminary point temp/pops...

Today sun Monday Tuesday Wednesday Thursday Friday
bil 099 061/097 062/096 064/089 061/086 060/087 059/083
0/u 00/u 02/T 23/T 24/T 43/T 22/T
lvm 096 054/094 056/092 057/085 055/083 053/084 052/081
0/u 00/u 02/T 33/T 24/T 43/T 22/T
hdn 099 057/100 059/099 063/091 059/088 059/088 057/085
0/u 00/u 02/T 23/T 23/T 33/T 22/T
mls 100 060/098 062/096 065/087 062/089 062/086 060/085
0/u 00/u 01/u 33/T 33/T 44/T 33/T
4bq 098 059/099 060/094 062/086 060/088 060/086 059/085
0/u 00/u 01/b 24/T 33/T 33/T 33/T
bhk 096 057/094 058/091 060/082 058/085 058/082 058/081
0/u 00/u 01/u 34/T 33/T 44/T 33/T
shr 095 055/097 057/094 058/088 056/086 055/085 054/084
0/u 00/u 02/T 33/T 33/T 33/T 22/T


Byz watches/warnings/advisories...



National Weather Service Glossary of Abbreviations