FXUS65 KGGW 242019 
  AFDGGW 
   
  AREA FORECAST DISCUSSIONAREA FORECAST DISCUSSION
This National Weather Service
product is intended to provide a
well-reasoned discussion of the
meteorological thinking which went
into the preparation of the Zone
Forecast Product. The forecaster
will try to focus on the most
particular challenges of the
forecast. The text will be written
in plain language or in proper
contractions. At the end of the
discussion, there will be a list of
all advisor...
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  NATIONAL WEATHER SERVICENATIONAL WEATHER SERVICE
An agency of the Federal Government
within the Department of Commerce,
National Oceanic and Atmospheric
Click for More... GLASGOW MTMT
1. Mountain or 2. Montana
Click for More... 
  219 PM MDTMDT
1.Moderate 2.Mountain Daylight Time
Click for More... MON AUG 24 2009 
   
  .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY... 
   
  A FEW ISOLATED SHOWERS STILL CURRENTLY EXIST ACROSS THE 
  SOUTHEASTERN PORTIONS OF NEMONT TERRITORY. DIRECTLY BEHIND THE 
  SHOWERS AND ACROSS THE MAJORITY OF THE CWACWA
County Warning Area
Click for More... LIES A NN
North
Click for More... AREA OF 
  CLEARING WHICH SHOULD REACH THE REMAINDER OF THE CWACWA
County Warning Area
Click for More... BY EARLY THIS 
  EVENING. PATCHY FOGFOG
(abbrev. F) Fog is water droplets
suspended in the air at the Earth's
surface. Fog is often hazardous
when the visibility is reduced to ¼
mile or less.
Click for More... WILL PROBABLY BE A PROBLEM FOR AREAS IN AND 
  AROUND YELLOWSTONE RIVER VALLEY AND EASTERN MOST PORTIONS OF THE 
  MISSOURI RIVER VALLEY. THE THOUGH PATTERN BEHIND THIS IS THAT CLOUD 
  COVER IN THESE PORTIONS OF THE STATE WILL EXIT NEAR SUNDOWN 
  ALLOWING AN LEFT OVER RAIN RAISED DEWPOINTS TO REMAIN IN PLACE DUE 
  TO THE EVENING INVERSIONINVERSION
(abbrev. INVRN) Generally, a
departure from the usual increase
or decrease in an atmospheric
property with altitude.
Specifically it almost always
refers to a temperature inversion,
i.e., an increase in temperature
with height, or to the layer within
which such an increase occurs. An
inversion is present in the lower
part of a cap.
Click for More... RATHER THAN BE MIXED OUT INTO THE FREE 
  ATMOSPHEREATMOSPHERE
The air surrounding and bound to
the Earth.
Click for More.... NAMNAM
The operational North Amercian Meso
(NAM, formerly Eta, currently the
same as the WRF) is run four times
per day (00,06,12,18Z), all cycles
run to 84-h.
Click for More... BUFFER SOUNDINGS SHOW A GOOD DEAL OF DRY AIR 
  SUBSIDENCESUBSIDENCE
1. A descending motion of air in
the atmosphere occurring over a
rather broad area.
Click for More... DIRECTLY OVERHEAD LEADING TO VERY GOOD RADIATIVE 
  COOLING EFFECTS BY THE MORNING HOURS.  
   
  TUESDAY THROUGH TUESDAY NIGHT... OVERHEAD HIGH PRESSURE WILL 
  FURTHER SPILL INTO THE REGION ALONG WITH 850 TEMPERATURES INTO THE 
  20S. THIS SHOULD PROVIDE SUPPORT FOR A WARMING TREND TO OVERTAKE 
  THE REGION AND CREATE A STRONG CHANCE FOR ABOVE NORMAL 
  TEMPERATURES ACROSS THE CWACWA
County Warning Area
Click for More.... TO THE WEST A LEES SIDE MOUNTAIN 
  TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... WILL BEGIN TO BUILD IN AND ENHANCE SOUTHEASTERN FLOWFLOW
(abbrev. FLW) Wind. In meteorology,
a qualitative reference of an air
parcel(s) with respect to its
direction of movement, sometimes
specified at a certain height or
pressure elevation, e.g. westerly
flow at 500 mb. In hydrology, the
volumetric flow of water past a
given point on a stream or river,
usually in cubic feet per second
(cfs)
Click for More... ALONG 
  WITH WAAWAA
Warm Air Advection - the advection
(movement) of warm air into a
region.
Click for More... AND WEAK MOISTUREMOISTURE
Refers to the water vapor content
in the atmosphere, or the total
water, liquid, solid or vapor, in a
given volume of air.
Click for More... ADVECTIONADVECTION
(Abbrev. ADVCTN)- Transport of an
atmospheric property by the wind.
Click for More.... NEEDLESS TO SAY CLEAR TO 
  PARTLY CLOUD SKIES AND DRY CONDITIONS SHOULD BE EXPECTED THROUGH 
  THE WHOLE OF THESE PERIODS. 
   
  WEDNESDAY... A QUICK MOVING SHORTWAVESHORTWAVE
Also known as Shortwave Trough; a
disturbance in the mid or upper
part of the atmosphere which
induces upward motion ahead of it.
If other conditions are favorable,
the upward motion can contribute to
thunderstorm development ahead of a
shortwave.
Click for More... WILL EJECT OFF THE FRONTFRONT
A boundary or transition zone
between two air masses of different
density, and thus (usually) of
different temperature. A moving
front is named according to the
advancing air mass, e.g., cold
front if colder air is advancing.
Click for More... 
  RANGE AND LATCH ON TO THE LEELEE
The side or part that is sheltered
or turned away from the wind, such
as with a mountain.
Click for More... SIDE MOUNTAIN TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... DRAGGING IT 
  ALONG FOR THE RIDE ALONG WITH SLIGHTLY COOLER AIR ACROSS NEMONT. 
  WHEN THIS LIFT ZONE IS COMBINED WITH PEAK DAYTIME HEATING A 
  SLIGHT CHANCE FOR SHOWERS WILL EXIST DURING THE AFTERNOON HOURS. 
  LOW MOISTUREMOISTURE
Refers to the water vapor content
in the atmosphere, or the total
water, liquid, solid or vapor, in a
given volume of air.
Click for More... CONTENT WILL ESSENTIALLY BE THE PROBLEM FOR THE 
  SCENARIO AND MAY TRANSLATE INTO MORE A VIRGAVIRGA
Streaks or wisps of precipitation
falling from a cloud but
evaporating before reaching the
ground. In certain cases, shafts of
virga may precede a microburst.
Click for More... STYLE EVENT DURING THE 
  PASSAGE. GAH 
   
   
  .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... 
  MODELS SEEM TO BE HITTING THE INFLUENCE OF A BACKDOOR COLD FRONTCOLD FRONT
A zone separating two air masses,
of which the cooler, denser mass is
advancing and replacing the warmer.
Click for More...  
  LATE THIS WEEK...SO LOWERED TEMPSTEMPS
Temperatures
Click for More... ACCORDINGLY. WINDS ALSO WERE  
  ADJUSTED TO LINE UP BETTER WITH FRONTAL PASSAGE. OTHERWISE...GOING  
  FORECAST WAS IN GOOD SHAPE. JAMBA 
   
  PREVIOUS DISCUSSION... 
  A LONGWAVE UPPER RIDGERIDGE
An elongated area of relatively
high atmospheric pressure; the
opposite of trough.
Click for More... WILL BE THE DOMINANT FEATURE THROUGH NEXT 
  WEEKEND. THIS WILL PROVIDE SEVERAL DAYS OF DRY AND WARM WEATHER. 
  WITH THE RIDGERIDGE
An elongated area of relatively
high atmospheric pressure; the
opposite of trough.
Click for More... AXIS EXPECTED TO BE ALONG THE CONTINENTAL DIVIDE... 
  EASTERN MONTANA WILL BE ON THE NWNW
Northwest
Click for More... FLOWFLOW
(abbrev. FLW) Wind. In meteorology,
a qualitative reference of an air
parcel(s) with respect to its
direction of movement, sometimes
specified at a certain height or
pressure elevation, e.g. westerly
flow at 500 mb. In hydrology, the
volumetric flow of water past a
given point on a stream or river,
usually in cubic feet per second
(cfs)
Click for More... ALOFT SIDE OF THE RIDGERIDGE
An elongated area of relatively
high atmospheric pressure; the
opposite of trough.
Click for More.... 
  MODELS ARE IN GOOD AGREEMENT WITH THE RIDGERIDGE
An elongated area of relatively
high atmospheric pressure; the
opposite of trough.
Click for More.... THEY DIFFER ON THE 
  PLACEMENT OF THE UPPER TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... TO THE EAST WHICH MAY MAKE A 
  DIFFERENCE ON HOW WARM NORTHEAST MONTANA IS DURING THE PERIOD. THE 
  ECMWFECMWF
European Center for Medium-Range
Weather Forecasts. Operational
references in forecast discussions
typically refer to the ECMWF's
medium-range numerical forecast
model, which runs out to 10 days.
Click for More... HAS THE TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... OVER MINNESOTA LATE IN THE WEEK WHILE THE GFSGFS
Global Forecast System - One of the
operational forecast models run at
NCEP. The GFS is run four times
daily, with forecast output out to
384 hours.
Click for More... 
  KEEPS IT IN HUDSON BAY. EITHER WAY...IT LOOKS LIKE NORTHEAST 
  MONTANA WILL SEE A DRY BACK DOOR COLD FRONTCOLD FRONT
A zone separating two air masses,
of which the cooler, denser mass is
advancing and replacing the warmer.
Click for More... ON THURSDAY WHICH WILL 
  MAKE TEMPERATURES SOMEWHAT COOLER ON FRIDAY. ECMWFECMWF
European Center for Medium-Range
Weather Forecasts. Operational
references in forecast discussions
typically refer to the ECMWF's
medium-range numerical forecast
model, which runs out to 10 days.
Click for More... IS MUCH 
  STRONGER THAN THE GFSGFS
Global Forecast System - One of the
operational forecast models run at
NCEP. The GFS is run four times
daily, with forecast output out to
384 hours.
Click for More... WITH THE COOLING GIVEN ITS TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... PLACEMENT 
  IS MUCH CLOSER TO MONTANA THAN THE GFSGFS
Global Forecast System - One of the
operational forecast models run at
NCEP. The GFS is run four times
daily, with forecast output out to
384 hours.
Click for More.... AT THIS POINT...THE ECMWFECMWF
European Center for Medium-Range
Weather Forecasts. Operational
references in forecast discussions
typically refer to the ECMWF's
medium-range numerical forecast
model, which runs out to 10 days.
Click for More... 
  IS PROBABLY COOLING TEMPERATURES TOO MUCH BETWEEN THURSDAY AND 
  FRIDAY WHILE THE GFSGFS
Global Forecast System - One of the
operational forecast models run at
NCEP. The GFS is run four times
daily, with forecast output out to
384 hours.
Click for More... IS NOT COOLING IT ENOUGH. 
   
  BEYOND FRIDAY...LITTLE MOVEMENT IN THE RIDGERIDGE
An elongated area of relatively
high atmospheric pressure; the
opposite of trough.
Click for More... AND TROUGHTROUGH
An elongated area of relatively low
atmospheric pressure, usually not
associated with a closed
circulation, and thus used to
distinguish from a closed low. The
opposite of ridge.
Click for More... IS 
  EXPECTED OVER THE WEEKEND SO TEMPERATURES WILL STAY ABOUT THE SAME 
  EACH DAY WITH LITTLE OR NO CHANCE OF PRECIPITATIONPRECIPITATION
The process where water vapor
condenses in the atmosphere to form
water droplets that fall to the
Earth as rain, sleet, snow, hail,
etc.
Click for More.... FORRESTER 
   
   
  && 
   
  .AVIATION... 
  SCATTERED SHOWERS THIS AFTERNOON OVER THE FAR EASTERN AREAS (GDV AND  
  SDY) ARE EXPECTED TO BE OUT OF THE AREA BY ABOUT 4 PM. LIGHT WINDS  
  AND CLEAR SKIES THIS EVENING MAY HELP TO GENERATE PATCHY FOGFOG
(abbrev. F) Fog is water droplets
suspended in the air at the Earth's
surface. Fog is often hazardous
when the visibility is reduced to ¼
mile or less.
Click for More... IN  
  THESE AREAS FOR LATE TONIGHT. TOO EARLY TO SAY WHAT VISIBILITIES  
  WILL BE ABOUT SUNRISE SO THIS WILL BE MONITORED CLOSELY. SUNSHINE IS  
  EXPECTED TO MAKE A RETURN TUESDAY WITH A LIGHT SOUTHEAST WIND. JAMBA 
   
   
  && 
   
  .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. 
   
   
  && 
   
  
 
   
  WEATHER.GOV/GLASGOW