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Area forecast discussion 
National Weather Service Grand Forks ND
1146 PM CST Tuesday Jan 27 2015

Update...
issued at 1146 PM CST Tuesday Jan 27 2015

Bumped up the western edge of the County Warning Area to areas of fog as coverage
has been less patchy in recent observation. Some locations down to 1/4sm
but think that it will be in and out of the lowest visibilities so
will just keep an eye on it for now and leave out headlines for
the time being.

Update issued at 936 PM CST Tuesday Jan 27 2015

Southeasterly winds and plenty of clouds continue...and some sites
in the western half of the County Warning Area have been dropping to around 1/2sm
in visibility. Some sites have come back up so the fog is pretty
patchy...but should stick around much of the night according to
the hrrr. Added in some patchy fog from the Red River westward.
Precipitation in southern Canada has pulled away from the northeastern
County Warning Area so dropped probability of precipitation we had going for after 06z.

Update issued at 640 PM CST Tuesday Jan 27 2015

Made a few minor tweaks to sky cover over the western counties as
higher clouds move in...but no major changes. Will keep some low
probability of precipitation going in our northeast as Flag Island reported a bit of snow
earlier.

&&

Short term...(this evening through Wednesday night)
issued at 308 PM CST Tuesday Jan 27 2015

Tough go of it today in trying to figure out what is going to
happen with the clouds. After things were fairly stagnant through
early afternoon there have been breaks developing from kdtl to
kfse. Therefore this will remain the challenge into tonight and
Wednesday. Other than the previously mentioned breaks the low clouds
lifted earlier from kbji to krox as well but these areas have middle
level clouds that replaced them. South-south-southeast winds at 10 to 20 knots
may be helping to scour things out...but will maintain the idea of
things remaining cloudy tonight. Winds should lose the gustiness
this evening but they look to remain steady at least in the 10-15
knot range. These steadier winds may be enough to keep the thicker
fog at Bay but there may still be some 2-5sm visibilities in mist around.
With the slightly higher expected visibilities will not mention in the
forecast itself. Later shifts can monitor.

There is also pretty strong 850mb warm advection tonight which
will also strengthen the low level inversion. Model soundings
look quite dry in the middle levels but lots of cirrus above that.
There has also been a steady stream of echoes from the Lake of The
Woods back northwest into southeast Saskatchewan. Main support
seems to be the upper jet and possibly some weak short wave energy
along it. Models seem to keep the idea of some minimal precipitation from
the northern Red River valley over into the Lake of The Woods
region. With the dry middle levels this may be more virga than
anything but will mention a mix possible in these areas. Kept
temperatures on the mild side due to the expected clouds and steady
winds...but all these bets are off if some areas clear out.
Continued the idea of a slower evolution to any additional precipitation
reaching the northern forecast area on Wednesday...as the latest European model (ecmwf) shows almost
nothing until closer to 00z Thursday in the far north. This continues
into Wednesday night as the main precipitation band remains in southern Canada.
May be more like flurries or very light snow along and north of
Highway 2. Looks like a period of breezier winds late Wednesday
afternoon into Wednesday night as well along with colder temperatures working
southward.

Long term...(thursday through tuesday)
issued at 308 PM CST Tuesday Jan 27 2015

Surface high builds in on Thursday with not a lot of temperature recovery
expected. One positive thing is the lack of snow cover. If there
is sun on Thursday it will warm up. As surface high shifts off to the
southeast on Friday will see return flow and slightly warmer highs.
May see a little light snow moving into the northeast forecast area Friday
afternoon.

For Friday night through next Tuesday...the extended period
highlights include colder temperatures and a relatively dry
pattern. The period starts off with northwest flow aloft with an
upper level short wave moving through the region and an upper low
centered over western Hudson Bay. A surface low pressure system
will be centered over the Dakotas Friday night and the associated
cold front will move through the area overnight. Temperatures may be
falling during day on Saturday...depending on the strength of the
front. An Arctic plunge is then expected for the rest of the
weekend and into Monday as highs will likely be in the single
digits or slightly below zero on Sunday and Monday. Weak upper
level waves on Friday night...Saturday night...and Monday
night...may skirt the area...possible producing a dusting of snow.
No major snow producers are on the horizon...however.

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1146 PM CST Tuesday Jan 27 2015

Fog has developed in the western forecast area...with kdvl around
3/4sm. Think that the fog will remain mostly to the west...but
kgfk and kfar should see visible drop below 6sm in the next few hours
and be in the 2-5sm range overnight. Ceilings continue to be low...in
the 400-700 feet range in the valley and lower at kdvl. Stratus has
finally filled into the eastern counties and ktvf and kbji have
gone MVFR. Think that at least ktvf should dip down to IFR later
tonight. Most of the sites will see the low ceilings and visible lingering
through the rest of the night and into the morning...with LIFR
continuing at kdvl. Some improvement will be possible after 15z...but
IFR/MVFR ceilings will remain. Winds will continue out of the
before becoming light and variable in the morning. A frontal
boundary moving in after 20z will shift winds to the northwest and
kdvl could become quite breezy with gusts above 30 kts possible.
Think there should be some improvement on ceilings with conditions
MVFR at the end of the period.

&&

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

$$

Update...Jr
short term...godon
long term...godon/knutsvig
aviation...Jr

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