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Area forecast discussion 
National Weather Service Grand Forks ND
718 PM CDT Tuesday Apr 15 2014

Update...
issued at 708 PM CDT Tuesday Apr 15 2014

Coordinated with weather forecast office bis and idea was to greatly back off on probability of precipitation
this evening as very dry airmass with return flow out of dry high
moving into northwest Wisconsin will dry up most if not all the
snow from reaching the ground in middle level moisture band from
southeastern Saskatchewan into southeastern ND through 06z. Dew points will rise
but still remain in the teens in the Red River this evening before reaching
20s overnight. Main short wave energy will move from central
Montana into South Dakota with surface low strengthening as it
moves into central-eastern South Dakota by 12z Wednesday. Most of the forcing for lift
in the middle levels concentrates in far northern South Dakota into central Minnesota at 12z
skirting our far southeastern forecast area per advisory area. 12z Gem
was farthest south with main snow more so Watertown-Wilmar-St
cloud line versus more along a Sisseton-Elbow Lake-Brainerd axis.
Result of drier air will go dry in eastern ND through 06z and then keep
higher probability of precipitation after 06z in southeast ND into west-central Minnesota. 23z rap focuses
most snowfall just a bit south of where it did earlier more so
Milbank South Dakota into Morris Minnesota to Little Falls again skirting far south
with any sig snowfall and just very light amounts up toward Fargo
and little to nothing north of Fargo. Trimmed probability of precipitation and snow
amounts to reflect this thinking.

&&

Short term...(this evening through Wednesday night)
issued at 245 PM CDT Tuesday Apr 15 2014

Forecast challenge concerns mainly snow event later tonight into
Wednesday. Models seem to be coming into better alignment with
more significant snow band for Wednesday. GFS/NAM/Gem have trended
slightly southward with main snow band. European model (ecmwf) remains consistent
with less quantitative precipitation forecast through the event.

For tonight models in good agreement with band of light snow
spreading northwest-southeast across the forecast area. Does not appear to be a great deal
of upper forcing as main wave just crossing the northern rockies. Towards
morning as wave approaches 700 mb low becomes better organized over east
central South Dakota with favored frontogenetic forcing/q-vector convergence
along and north of low. So expect northwest-southeast oriented snow band to
become more east-west from eastern South Dakota-west central Minnesota with common ND
border area on northern fringe. Overall still looking at general
1-3 inches overnight. Mixing and clouds will limit temperature
drop overnight.

On Wednesday frontogenetic forcing/ q vector convergence shifts
due east from east South Dakota into S Minnesota. This will put far southeast forecast area on northern
and western fringe of heavier snow band. For this have issued
Winter Weather Advisory for 3-5 inches of snow. Snow ratios and if we
can get to or above melting will have a bearing on snow amounts.
Snow should begin to pull east middle afternoon.

Any lingering snow will diminish early evening. Not much colder air
wrapping around system and dependent on clouds will continue to
see temperatures below average especially with new snow fall.

Long term...(thursday through tuesday)
issued at 245 PM CDT Tuesday Apr 15 2014

High pressure to build in Thursday and with slightly warmer column
and middle April solar temperatures should recover in spite of fresh
snow.

Remainder of the work week looks quiet with moderating
temperatures.

Friday night to Tuesday...high confidence in a warm up across the
northern plains for Easter weekend into next week. Increasing
thicknesses as 500mb flow becomes more zonal and 850mb warm air advection begins
Saturday in which nwp indicates a potential for a band of warm air advection precipitation
from west to east to cross the area. Zonal flow continues Sunday
into Monday before more ridging Monday into Tuesday where guidance
is showing 60s for highs on Monday and Tuesday next week.

&&

Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 708 PM CDT Tuesday Apr 15 2014

Winds will be main hazard in the area next 24 hours as southeast
to east winds increase as low develops in South Dakota tonight and
moves into Minnesota Wednesday. Tight pressure gradient between
the low and high in Manitoba-northwest Ontario to have a strong east to
northeast surface wind over the area Wednesday with sustained 15
to 22 kts and gusts over 30 kts in places. Per moisture cross
sections should have mostly VFR ceilings through Wednesday in dvl-gfk-tvf-bji
areas with light snow MVFR visibilities and ceilings in Fargo late tonight
into Wednesday midday. Some areas of MVFR ceilings possible dvl-gfk-tvf-bji as
well but feel it should stay more on the low end VFR range. Did
have some light snow into bji 15z Wednesday but that is much more
uncertain as more data comes in.

&&

Hydro...the cold nights and cool daytime highs are putting a
damper on any additional runoff. Was able to issue last forecasts
for Sabin Dilworth and Grafton. The remaining points in hydrologic
statements or flood statements are all at or north of Grand Forks.
Only sites still rising are Drayton and Pembina on the Red River.
Still anticipate the cooler weather lasting into Thursday with
some moderation coming by late week into the weekend. The next
storm system for tonight into Wednesday night looks to mainly
affect portions of west central Minnesota with little or no
precipitation over the northern Red River valley.

&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...Winter Weather Advisory from 4 am to 6 PM CDT Wednesday for
mnz030>032-040.

&&

$$

Update...Riddle
short term...voelker
long term...jk/voelker
aviation...Riddle
hydrology...vg