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Area forecast discussion 
National Weather Service Grand Forks ND
1131 PM CDT Friday Apr 18 2014

Update...
issued at 950 PM CDT Friday Apr 18 2014

Will be able to allow the Wind Advisory to expire at 10pm for the
Devils Lake basin. Across the remainder of the Wind Advisory
area...winds continue to be within advisory criteria across much
of southeast North Dakota. Into the valley area...winds are
finally increasing and anticipate periods of advisory criteria
conditions into the early morning hours.

An area of rainfall is currently propagating across North
Dakota...ahead of the upper low. Most areas across the northern forecast area
should receive rainfall (more scattered across the southern
fa)...and the current forecast handles this well. Into the NE forecast area
(lake of the Woods area)...mixed p-types still possible.
However...Road surface temperatures are currently near 50f...and
any frozen precipitation should not pose any problems.

&&

Short term...(this evening through Saturday night)
issued at 320 PM CDT Friday Apr 18 2014

Intense surface low and upper low over central Saskatchewan will move east
through central Manitoba tonight into Ontario Saturday. A
secondary low will move along the ND/South Dakota border but most of the
forcing will be with the Canadian low. Radar returns showing up in
southern Manitoba and far northern ND but surface observation and webcams show
no precipitation yet hitting the ground as dry sub 925 mb airmass remains
in place. Saturation will occur as 925 mb winds turn a bit more
southerly this evening. Speaking of winds...an area of 30-40 knots
surface winds this afternoon Wheaton Minnesota up through Jamestown-Valley City
through dvl basin-Minot. As the 925 mb winds shift a bit more
southerly the highest winds (50 kts at 925 mb) will become more
south-north oriented in the Red River this evening and then more
southwest to northeast overnight. Will need to watch winds closely
as wind advection may well have to continued past 00z in some areas and
also as higher 925 mb winds move into the northern valley. But not
confident yet as strong inversion develops and this may keep a lid
on wind speeds just enough. Precipitation will expand or develop eastward
this evening so kept high probability of precipitation especially 03z-06z NE ND and into northwest Minnesota
06z-12z. For ptype looking at mostly rain all but far northeastern
forecast area. Question arises on if a Winter Weather Advisory is needed
for Lake of The Woods County. All models keep a tight 925 mb temperature
gradient along the Steinbach-Warroad-Baudette-Grand Rapids Minnesota
line. Most model forecast surface temperatures from rap/hrrr has temperatures at 32-33
in Baudette at 09z. So going to be close call. Using top down
ptype there will be snow/sleet mix to start maybe freezing precipitation
at Flag Island-Oak Island in far northern low County. It would go to
rain by 12z. Just how long wintry precipitation will be and surface temperatures is
key and too uncertain to issue an advisory at this time as if any
snow/sleet falls at 33 degrees it wouldnt cause big issues.

Storm Prediction Center had southeast ND/west-central Minnesota in 10 percent thunder area 04z-10z. Not
impossible as low level jet in place but moisture not great at 850
mb level and showwalter indices stay above 0c. So left out any
thunder mention.

Systems moves east and skies clear quickly Sat morning in eastern ND
and by middle to late morning in northwest/west-central Minnesota. Temperatures will warm nicely
with west winds getting highs into the upper 50s to middle 60s.

Clear Sat night as high overhead.

Long term...(sunday through friday)
issued at 320 PM CDT Friday Apr 18 2014

Sunday will see warm advection ahead of next upper low set to move
through southern Canada. This is a bit weaker than last one but
southerly winds ahead of it will draw up warmer air with highs middle
60s to lower 70s Easter Sunday. Cold front will move through Sun
night with chance of showers. Canadian model has middle 50 dew points Sun
night which seem high....but might be a bit more instability sun
evening for a thunderstorm. Kept it out again with low confidence. But
quick shot of rain then west winds and a bit cooler 850 mb air
Monday. Models vary greatly in amount of 850 mb cooling with GFS
coolest and NAM warmest. Using model blend still gives highs middle
50s to middle 60s...though GFS would bring warparound stratocu and
colder temperatures southward more than other models. Do have a low chance
of showers far northeast due to wraparound moisture and cold advection.

Long term (mon night through friday)...
upper ridge to begin extended period portends the only dry day in
the forecast with temperatures at or above average values. The scenario
becomes more active for middle to late week with the latest European model (ecmwf)
coming into agreement with the previous and current GFS runs
offering a slower solution featuring colder air (sub 0 850 temps) by
Friday.

Main system enters Dakotas later Wednesday...major guidance
winds it up with bowling Ball 500 mb low threatening to capture and
stall the eastward progress by late Thursday. Not much instability
early on so went showery Wednesday into Thursday until cold pool
aloft enters the picture Thursday afternoon helping to generate some
convection. Colder air to the northwest comes down later Thursday
night into Friday changing precipitation to snow showers. We may be high with
Friday maximum temperatures but this can be monitored and adjusted as time GOES
by.

&&

Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1131 PM CDT Friday Apr 18 2014

Rainfall to affect areas mostly north of our sites...but there
could be a brief period of -shra at all sites. There could be a
brief period of MVFR ceilings...but chances for this are very low.
Anticipate winds to remain strong...then gradually decrease from
west to east by sunrise. Winds will become westerly Saturday
morning/early afternoon...and will be gusty at times Saturday
afternoon.

&&

Fgf watches/warnings/advisories...
ND...Wind Advisory until 4 am CDT Saturday for ndz008-016-026>030-038-
039-049-052>054.

Minnesota...Wind Advisory until 4 am CDT Saturday for mnz001>004-007-029-030-
040.

&&

$$

Update...tg
short term...Riddle
long term...wjb/Riddle
aviation...tg