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Area forecast discussion...updated 
National Weather Service Billings Montana
849 PM MDT Wednesday Oct 22 2014


Trends looking good need for update. Reimer


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

The upper low and cold front that blasted across the forecast
area with mainly wind last evening has pushed well east into
southern Canada and the Dakotas today. High pressure ridging and
subsidence behind the front has resulted in sunny skies...although
cooler temperatures...across the area today. However...this will
be short-lived as another disturbance currently moving onto the
Pacific northwest coast will bring increasing clouds to our area
on Thursday. But for tonight...expect clear to mostly clear skies
along with cooler overnight lows.

The ridge gets flattened Thursday as the next system moves onto
the Pacific northwest coast and across the northern rockies. At
the same time...a surface low develops and moves across southern
Canada allowing for a Lee-side trough to develop across our area
bringing a returned downslope flow across our central and western
areas with 850mb temperatures rebounding into the 15-17c range.
Clouds will be on the increase during the afternoon and evening as
another cold front approaches the area. The front is expected to
move across the area during the late afternoon/evening hours. Low-
level moisture and dynamics are lacking so no precipitation is expected
except for a slight shower chance over the beartooth/Absaroka
Mountains. Expect breezy conditions Friday especially across the
eastern areas. Temperatures will once again cool down Friday but
readings will remain above normal in the 60s. Hooley

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

Main take away from the extended models is that there is much
better agreement between the models this run and that there is
definitely a pattern shift in progress going into next week with a
more progressive flow off the Pacific and more jet energy building
into the southwest U.S. Where a ridge has persisted for the past
several weeks.

The latest GFS run flip-flopped off its previous trough forecast for
the middle to late next week time frame and trended toward the
drier European model (ecmwf) solution. This brings the models into good agreement
again for the weekend into the middle of next week. System for
Sunday has trended slower leading to a more amplified ridge over
the area Saturday...and have temperatures above guidance with
sunny dry conditions Saturday afternoon. Progressive trough pushes
through the area Sunday and Monday. Energy is dis-jointed and a
downslope wind gradient remains in place so kept lower elevation
low with the best precipitation chances in the mountains. Heights
increase on Tuesday under progressive west to northwest flow for
mainly dry and slightly warmer conditions. Jet stream off the
Pacific will push a good deal of Pacific moisture through the area
which will limit heating and cap temperatures. Another area of
weak energy crosses the area Wednesday along with a surge of
Pacific moisture aloft. Kept low probability of precipitation in for this feature and
cloud cover will again limit heating holding temperatures near
seasonal levels.

For the later extended the GFS had developed a storm system over
the area in the Thursday-Saturday time frame...but the latest runs
have flopped to an amplified ridge similar to the European model (ecmwf). Deepening
southerly flow would bring warm and dry conditions to the area for
the end of the week. For those hoping for more Fall like
weather...the cfs long range forecasts continue to hint at a
pattern change to colder than normal temperatures and unsettled
conditions for the first week of November. Chambers



VFR conditions will continue across the area for the rest of tonight
and Thursday. Winds will continue to be gusty overnight mainly in
the foothills...especially at Livingston where gusts will still
be 25 to 30 knots. Reimer


Preliminary point temp/pops...

Thursday Friday Sat sun Monday Tuesday Wednesday
bil 042/070 048/064 042/070 043/059 036/054 032/056 040/058
00/b 10/b 00/u 02/west 22/west 11/u 12/west
lvm 041/068 045/063 041/069 043/052 031/049 030/053 036/054
00/north 11/north 10/u 13/west 32/west 11/u 22/west
hdn 038/073 043/070 038/072 040/062 035/055 029/058 036/060
00/b 00/b 00/u 02/west 22/west 11/u 12/west
mls 037/072 043/068 041/070 042/063 038/053 030/056 037/056
00/u 00/b 00/b 02/west 21/north 11/u 12/west
4bq 037/071 042/069 039/071 045/062 037/054 031/056 036/058
00/u 00/b 00/u 02/west 22/west 11/u 12/west
bhk 035/070 041/067 037/065 040/061 036/051 028/051 035/054
00/u 00/b 00/b 02/west 21/b 11/b 12/west
shr 032/072 041/068 037/073 040/063 032/053 026/057 029/059
00/b 00/b 00/u 02/west 32/west 11/u 12/west


Byz watches/warnings/advisories...



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