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Area forecast discussion 
National Weather Service Grand Forks ND
1224 PM CDT sun may 24 2015

Update...
issued at 1219 PM CDT sun may 24 2015

Rain having a tough time spreading northward in line with current
high resolution models. Trimmed back on probability of precipitation through middle afternoon
keeping best chances confined to southeast forecast area border area. Remainder of
forecast OK.

Update issued at 930 am CDT sun may 24 2015

Weak radar returns continue to lift NE and weaken...mainly across
the far southeast forecast area. Will maintain isolated/scattered mention across the far S.
Overall current forecast good so no changes planned.

Update issued at 711 am CDT sun may 24 2015

Not much change. Very short range models differ a bit on how far
north and how much showers will advance north today. Hrrr/rap a
bit drier... hop WRF from weather forecast office mpx and arw-WRF a bit more
aggressive for precipitation into southeast ND. Radar at 12z shows some very
light rain along the South Dakota/Minnesota border in the Ortonville area. This is
prognosticated to move north and likely fizzle out some this morning.
Additional showers will likely form in South Dakota and move north. Sped up
probability of precipitation just a tad for blending with weather forecast offices mpx/abr...but otherwise no
changes.

&&

Short term...(today through monday)
issued at 320 am CDT sun may 24 2015

Another day and another model run where NCEP models...along with
Canadian and European model (ecmwf)...continue to delay the precipitation arrival
northward into eastern ND/northwest Minnesota. All models also are much farther
south and east with main quantitative precipitation forecast from system and have very little to
no quantitative precipitation forecast north of Devils Lake-Grand Forks-Thief River Falls. So made
adjustments to probability of precipitation accordingly.

For today...will see northward advance of high and middle level cloud
cover. NE ND/northwest Minnesota to see still a good deal of sun and with a warm
start...expect to see highs in the upper 70s. There is a narrow
band of light rain showers Pierre South Dakota to about Brookings South Dakota moving
north. Most models have this moving north toward the ND border
midday and into southeast ND/parts of west-central Minnesota this afternoon before drying
it up. Will delay onset of probability of precipitation in southeast ND/west-central Minnesota until more late
morning-early afternoon. Another surge of moisture will arrive tonight
into Monday as upper air trough moves northeast and surface low moves
from western Missouri through Iowa to east central Minnesota. Rain
with this system will be more widespread but track of low and
trough is a bit farther east and with high pressure holding strong
in Manitoba..it is looking more and more likely that any
significant precipitation will be Fargo-Bemidji and south and east with
very little to none north of dvl-gfk-tvf.

Long term...(monday night through saturday)
issued at 320 am CDT sun may 24 2015

Rain showers will diminish over west-central-north central Minnesota Monday night as
systems moves east. Tuesday will start off dry...but then enough
instability along the Canadian border just south of a weak front
near a Yorkton-Winnipeg-Kenora line to generate a few T-storms Tuesday
aftn/night. Looks quite warm with high temperatures upper 70s to lower
80s.

For Wednesday through Saturday...
region will be under the influence of mainly zonal flow at
beginning of extended period with a weak surface boundary draped
across S mb into Ontario. Boundary sagging slowly south into a
warm and unstable airmass justify low probability of precipitation first over northern
forecast area moving south by later Wednesday. A more significant
surface low taking shape over north/Central High plains will head
east Thursday favoring more shower/thunder chances...especially
over southern half of region.

By Friday cooler Canadian high pressure will take over suppressing
precipitation to Central Plains and bringing below seasonal temperatures with highs
in 60s and lows in 40s.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1219 PM CDT sun may 24 2015

VFR conditions expected through this period. The one
exception could be kfar. Rap/hrrr guidance suggest that although
rain will move into kfar this evening...ceilings and visibility will remain
VFR. 12z models have trended slightly south with the heavier
rainfall (where MVFR conditions are more likely)...so the rap/hrrr
guidance makes sense.

&&

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

$$

Update...voelker
short term...Riddle
long term...wjb/Riddle
aviation...tjg

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