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Area forecast discussion 
National Weather Service Grand Forks ND
942 am CDT Wednesday may 27 2015

Update...
issued at 941 am CDT Wednesday may 27 2015

Morning update focuses on slowing down showers and storms expected
to move across North Dakota tonight. Latest RUC and hrrr show a
diurnally related band of showers/storms in the late afternoon. Do have
some low probability of precipitation in western zones for this activity...but will not
adjust too much until newer runs come in. 06z runs were slower
than forecast grids on main precipitation entering western zones...and hrrr
is supporting a later start time (nearer 06z). Have cut back on
evening probability of precipitation per latest guidance

Update issued at 659 am CDT Wednesday may 27 2015

North wind around 10 kts into NE ND/northwest Minnesota bringing in some drier,
more stable airmass. Some middle level moisture....and do expect some
middle cloud patches today. Late afternoon...hrrr/rap are indicating
some isolated convection a bit farther east than previous runs did as far
east as Fargo-Fergus Falls. Thus did add isolated thunder for a few
hours late afternoon into southeast ND/west central Minnesota. This matches well with
abr/mpx.

&&

Short term...(today through thursday)
issued at 315 am CDT Wednesday may 27 2015

Surface trough passed through last evening. A bit more stable and
drier airmass over the area today...but later this afternoon some
instability returns to far western forecast area. Hrrr/rap do have a
couple of small cells in that dvl-vcy area so kept our low pop we
had.

Main short wave will move northeast from Wyoming and into western/central
ND tonight into the Red River 12z-18z period. 30 knots 850 mb jet and an
area of elevated instability present will be sufficient to keep
an area of showers and thunderstorms in tact as it moves toward
and into the area overnight into Thursday. Storm Prediction Center has marginal risk
of severe weather Thursday. Models in fair agreement with main short
wave center and surface low moving to near gfk midday with a cold
front southwest. Out ahead of this cold front and south of the low
mu convective available potential energy in the 1000-1500 j/kg range and negative showalterswould
support thunderstorms. But bulk shear is weak in the afternoon with the
cold front. Thus severe threat pretty limited.

Long term...(thursday night through tuesday)
issued at 315 am CDT Wednesday may 27 2015

Precipitation chances will Thursday night as high pressure and north winds and
a cooler airmass move in from the north. Friday will be breezy and
cool. High pressure will move into SW Manitoba Friday night and
center of ridge and light winds over north central ND means a good
chance for frost in this area.

For Saturday through Tuesday...will start off with nearly zonal flow
aloft and high pressure at the surface. For this reason the forecast
will start off dry for Sat/Sat night. All model solutions show a
wave passing through on Sunday...the GFS a little faster than the other
models...and bringing some precipitation to most of the area. More spotty
precipitation for Sun night/Monday as surface low sets up over the western High
Plains with warm front extending out to the east. Flow shifts to the
southwest Monday night/Tuesday with models diverging quite a bit in precipitation
placement. HPC guidance handles this by broadbrushing precipitation chances
everywhere during this period and will keep as is for now. Temperatures
start off on the cool side for Sat/sun then more normal by
Mon/Tue.

&&

Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 659 am CDT Wednesday may 27 2015

VFR through 06z Thursday. Do expect some scattered to occasional broken middle clouds today.
North-northwest wind 10 kts or so turning more east tonight. Isolated
thunder possible dvl-far areas but too low of a risk to mention in
taf. Better risk of showers or thunderstorms in dvl region after 06z Thursday.



&&

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

$$

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

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