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Area forecast discussion 
National Weather Service Grand Forks ND
1144 PM CDT Thursday Mar 26 2015

Update...
issued at 1139 PM CDT Thursday Mar 26 2015

High pressure ridge over the Red River valley at 04z. Skies clear
with first area of thin high clouds over central ND. Expect
thickening of the high clouds overnight into eastern ND. Forecast trends
looks fine and no further changes needed.

&&

Short term...(this evening through Friday night)
issued at 332 PM CDT Thursday Mar 26 2015

Short term forecast challenge will be temperatures and timing/placement
of snowfall on Friday. The models are in general agreement on
Friday...so went with NAM dng model guidance for better temporal
resolution.

Tonight...cumulus field should dissipate near Sundown and eastern
portion of County Warning Area should be partly cloudy to mostly clear...with some
middle level cloud impacting the west. The clearing in the far east
and dry air mass will help overnight lows there reach single
digits...while clouds in the far west could keep overnight lows in
the 20 degree range...so a large range for overnight lows tonight
depending on sky cover. A vorticity maximum will move into southern Canada and
increase clouds in the west near morning...but have removed probability of precipitation
through 12z.

Tomorrow and tomorrow night...sharp band of isentropic lift enters
western County Warning Area in the 15z to 18z timeframe. 540 thickness lines stays
west of County Warning Area so all snow expected. NAM 290k surface shows lift from
about 800mb to 670mb...so increased the snow ratios to around 20:1
in regions of best isentropic lift. Overall could see a couple of
inches in Devils Lake region...possibly localized in the 2 to 4
inch range but not widespread. Best snowfall rates should shift
from dvl area to southeast ND in the evening...and end after
midnight.

Long term...(saturday through thursday)
issued at 332 PM CDT Thursday Mar 26 2015

Saturday will be dry with an upper ridge aloft. Next system moves
in Saturday night into Sunday...with warmer airmass should bring
all rain to southern half of the County Warning Area...however colder air
indicated with decreasing thickness values indicate a potential for
rain changing over to snow in the north late Sat night. With a
quick warmup expected Sunday...any lingering precipitation in the far
east will be rain.

Western ridge maintains enough amplitude early next week to keep forecast area
in northwest middle level flow. Next minor wave will drop through Monday for
some light rain chances. Although models differ on timing next more
significant wave to affect forecast area from late Tuesday night through
midweek. Initially thermal profiles support -ra however as column
cools could see a mix or some light snow later Wednesday.
Temperatures through most if not all of the period will range above
average.

&&

Short term...(this evening through Friday night)
issued at 332 PM CDT Thursday Mar 26 2015

Short term forecast challenge will be temperatures and timing/placement
of snowfall on Friday. The models are in general agreement on
Friday...so went with NAM dng model guidance for better temporal
resolution.

Tonight...cumulus field should dissipate near Sundown and eastern
portion of County Warning Area should be partly cloudy to mostly clear...with some
middle level cloud impacting the west. The clearing in the far east
and dry air mass will help overnight lows there reach single
digits...while clouds in the far west could keep overnight lows in
the 20 degree range...so a large range for overnight lows tonight
depending on sky cover. A vorticity maximum will move into southern Canada and
increase clouds in the west near morning...but have removed probability of precipitation
through 12z.

Tomorrow and tomorrow night...sharp band of isentropic lift enters
western County Warning Area in the 15z to 18z timeframe. 540 thickness lines stays
west of County Warning Area so all snow expected. NAM 290k surface shows lift from
about 800mb to 670mb...so increased the snow ratios to around 20:1
in regions of best isentropic lift. Overall could see a couple of
inches in Devils Lake region...possibly localized in the 2 to 4
inch range but not widespread. Best snowfall rates should shift
from dvl area to southeast ND in the evening...and end after
midnight.

Long term...(saturday through thursday)
issued at 332 PM CDT Thursday Mar 26 2015

Saturday will be dry with an upper ridge aloft. Next system moves
in Saturday night into Sunday...with warmer airmass should bring
all rain to southern half of the County Warning Area...however colder air
indicated with decreasing thickness values indicate a potential for
rain changing over to snow in the north late Sat night. With a
quick warmup expected Sunday...any lingering precipitation in the far
east will be rain.

Western ridge maintains enough amplitude early next week to keep forecast area
in northwest middle level flow. Next minor wave will drop through Monday for
some light rain chances. Although models differ on timing next more
significant wave to affect forecast area from late Tuesday night through
midweek. Initially thermal profiles support -ra however as column
cools could see a mix or some light snow later Wednesday.
Temperatures through most if not all of the period will range above
average.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1139 PM CDT Thursday Mar 26 2015

Not much change was needed from the 00z taf issuance. Latest model
data shows trend of bringing in thickening high clouds into dvl
region overnight and into the Red River just prior to dawn. Followed by
middle clouds during the day. Area of light snow will spread into the
dvl region late morning into the afternoon. Kept -sn out of gfk/far for
now as eastern edge may be hard to saturate. In snow area could be
some MVFR ceilings and IFR visibilities (dvl region). Winds turning south-southeast
10-20 kts Friday.

&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Update...Riddle
short term...speicher
long term...speicher/voelker
aviation...Riddle

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