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Area forecast discussion 
National Weather Service Bismarck ND
151 am CDT Thursday Apr 24 2014


Issued at 151 am CDT Thursday Apr 24 2014

Expanded the coverage of fog this morning based on latest
observations. Will maintain low probability of precipitation east and north through 10z
with radar still showing some light activity over or near these

Other edits with this forecast update consisted of adjusting
hourly weather elements based on latest observations and near
term model trends.

Update issued at 942 PM CDT Wednesday Apr 23 2014

Late evening update for minor tweaks to overnight probability of precipitation trends and
temperatures. Have added some fog across the north central into
the James River Valley...areas that correspond with some of the
higher rainfall amounts...and where the winds will slacken
somewhat overnight.

Update issued at 639 PM CDT Wednesday Apr 23 2014

Evening update to cancel Wind Advisory for the east and southwest
and ob sites have dropped below advisory criteria and will
continue to diminish through the evening. Also made some
adjustments to probability of precipitation overnight and cleared them out sooner.


Short term...(this evening through thursday)
issued at 354 PM CDT Wednesday Apr 23 2014

A surface low/trough is currently located over western North
Dakota. Ahead of the cyclone...gusty southeasterly winds continue
over portions of central and eastern North Dakota. As the low
continues to push east...gusty westerly/northwesterly flow is
developing over southwestern North Dakota. Will allow the Wind
Advisory to expire over central North Dakota at 4 PM CDT...and
will maintain the wind advisories over the eastern County Warning Area (for gusty
southeasterly winds) and expanded the Wind Advisory north over
southwestern North Dakota to include Golden
Valley...Billings...and Stark counties (for gusty
westerly/northwesterly winds) until 7 PM CDT.

Numerous rain showers will also continue to rotate northeastward
over the state this afternoon and evening as the surface trough
slowly meanders across North Dakota. The southeastern County Warning Area could
see some rumbles of thunder later this afternoon and evening. organized severe weather is expected.

Overnight...winds will diminish and precipitation chances will taper
off from west to east as western and central North Dakota gets dry
slotted from the southwest.

By Thursday...some wrap around moisture will generate a slight
chance of showers over northern North Dakota. The position of the
upper low (colder temperatures aloft) will allow for elevated lapse rates
to become conducive for thunderstorm development across the north.
Once organized severe weather is expected.

Long term...(thursday night through wednesday)
issued at 354 PM CDT Wednesday Apr 23 2014

The NAM and European model (ecmwf) models were used this forecast package as the GFS
was an outlier with the placement and timing of main synoptic

A closed upper level low over southern Saskatchewan and Manitoba on
Thursday evening will move east along the international border
through Friday bringing a slight chance of showers to mainly the far
northern and eastern portions of the forecast area. This morning's
model run the models were building the shortwave ridge more
prominently northward into the Dakotas ahead of the next system.
This will raise temperatures Friday and Saturday from that of the
previous forecast package...keeps a cold front farther north along
or north of the Canadian border...and will keep the snow chances out
of the forecast through Friday. Looking at highs Friday from the
lower 50s to lower 60s.

The next system begins to affect the forecast area Friday
a large upper level longwave trough digs and a large surface low
develops in the Lee of The Rockies near Colorado. The leading edge
of a series of upper level shortwave energy impulses reaches
southwestern North Dakota Friday evening...lifting north and east
Friday night through Saturday. Look for chances of rain showers
beginning in the southwest Friday night and spreading across the
state on Saturday. North Dakota will still be in the warm sector of
the system Friday night and Saturday...with gusty east to southeast
winds. Warm and windy Saturday with scattered showers - possible
afternoon thundershowers - with highs in the 50s.

Sunday and Monday...the closed upper level low in the base of the
longwave trough emerges into the southern/Central Plains. The
associated surface low develops as a stacked system beneath the
upper low...and keeping low level and middle level moisture streaming
northwestward from the Gulf/Mississippi Valley and bringing good
chances of rain for all of western and central North Dakota.

These rains could be the first widespread soaking rains to begin
green-up in the Grasslands...with soil temperatures warming for
grass growth.

Dry Tuesday and Wednesday as the system moves into the Ohio and
Mississippi valleys.


Aviation...(for the 06z tafs through 06z Thursday night)

Issued at 151 am CDT Thursday Apr 24 2014

Overnight light fog is most favored at kmot and kjms...locations
that received some of the higher rainfall amounts and where the
wind is expected to slacken somewhat during the early morning.
Convective showers may re-develop at kmot-kisn-kjms Thursday
afternoon...otherwise VFR conditions expected through the period.


Bis watches/warnings/advisories...



Update...New Hampshire
long term...jv